I've been working this angle for a while finally got around to doing something about it. I was looking at a dual lift pump install if you look in my pic here http://dieselplace.com/forum/showthread.php?t=15002 the extra elbow below the vac switch is for the 2nd feed line pending install 2nd pump. Anyway got to looking at the IP inlet and saw it wasn't same size as the rest of my plumbing 3/16" OD roughly is OEM inlet size fitting, well "that ain't good enuff" for a stock rig IP OEM concept is okay, but watching EGT when hauling freight vs rpm vs lift pump pressure, more fuel is needed.

So I started thinking 2nd factory lift pump in parallel, key is volume not psi as if IP has too much psi it dumps back to the tank what it can't use.

Well GM has by design limited just how much flow one can possibly have. look over the attached photos and you will see what I'm talking about. What i fainally wound up with is 1/4" supply all the way to the IP. has is made a difference I think so, I got way more black smoke when I kick it in the rear until turbo spools up, more smoke = more fuel, I haven't had time yet to do last piece, install a Cummins lift pump & see what scanner says for fuel vs rpm data.

Special fitting made for IP inlet to replace OEM, then bored & tapped out the filter housing outlet pipe to accept 3/8 NPT X 1/4" OD barb fitting, hire professional machine shop to do your work if you tap too deep you will ruin the filter housing (YOU have been warned).

More pics

Your making me think about making some changes...... on second thought i've got all the black smoke i need at this point. Probably a great idea if not running a high output pump. With my dual filter set-up i should really be checking my LP pressure at the IP to see whats happening in there, maybe i do need to do that.

Great work and really nice pics!! :ro)

Glad to see ya got around to gettin' some things done. I was going to attempt your suggestion on modifying the fuel fittings, but then mine blew up again... Looks good IMO.

Excellent work, and great pictures to boot.
I recently upsized my puny supply return hoses to/from the IP, and I was pretty pleased with myself until you started this thread ;)

What are your fuel pressure readings like now at you IP? Just curious as I'm sure you must still be using the stock return fitting on the IP which has the little pressure control valve built into it.

Haven't plumbed the IP housing to know IP case pressure, yet, got the fitting just haven't plumbed it yet. The lift pump pressure, now more steady minimum now is 2 psi where before when I was gittin it, pressure would go down to .5 psi.

There are some clearance issues also to installing the fittings on the IP, I had to mill down the new IP inlet fittings flats to the same size as the old one so I could get a socket to fit on it and also clear the shut off solenoid. I also had a socket turned down for a little more clearance.

BTW the fitting was custom made to begin with, there must be a store bought one available but not here, but I know a good machinest that is fair on his labor so it was easier to have it made rather than track one down, for same money.

INTERESTING!! I like this, I have a spair LP and some time on my hands to make a little more fuel appear in my IP. I have a flow meter I might borrow from work. I will rig it up and see what kind of GPM flow the one LP has and post that and I will then link my spare with my current one and see a combined flow.

This is a CHEAP way to increase fuel!! I like cheap:D (and easy);)

Did a flow test on the Cummins electric supply pump verses the GM unit. I was quite surprised.

Used a flow meter calibrated in
PPH Liquid G. 0.81175 Visc. @ 95 degrees. using VISCOR test fluid (about the same as diesel)

Cummins Supply Pump
PSI-Flow PPH
9- 260
10 -242
11- 217
12 -184
13 -146
14 -115
15 -92

GM
4 -115
5 -94
6 -88


You'll have to convert that to gallons I guess. I guess you can see the GM unit is very lame. No wonder the unit loses pressure at speed. The flow meter is used in the calibration of Cummins PT type pumps on Cummins big engines.

Both tests made with good used units. From what I see the Cummins unit should be able to maintain 13 PSI on the GM at W.O.T.

Great work Turbine Doc.

Thanks.

Some more pics

Flow test an injection pump on the test stand to check for total flow through the pump and the injectors to get an Idea as to how much fuel flows through the pump and injectors. I used a rebuilt DS4-5521 injection pump. Please note different rates can be obtained by various pumps due to wear and return rates back to the tank.
I used a flow meter calibrated in PPH* Liquid G. 0.81175 Visc. @ 95 degrees. using VISCOR test fluid (about the same as diesel)

3000 rpm----70mm 3/stroke------165 PPH ----OEM Calibration
3400 " ------50mm----" --------140-"
3400 " ------20mm----"---------110-"

3000 "------80mm---- " --------180 -''-Maximum Pump output
3400 "------82mm-----"--------192--"------"-----"-----"

GM Supply pump
4PSI - 115PPH
5PSI - 94PPH - (desired pressure)
6PSI - 88PPH

At high full load demands the stock unit falls short. When the flow rate exceeds 94PPH the pressure will fall off.

*PPH > Pounds Per Hour ( pounds of fuel flowing through system in an hour)

I have been running a 2nd filter and a second lift pump for about 2 years,
All are in series... The ' add on ' lift pump is back by the tank, I switch it on when the fuel pressure drops under load.

The reason I did this is as follows:

Was not very confident that the OEM filter was very good at traping water
. I had never drained water from the OEM filter, therefore I installed additional filter before OEM lift pump. ( note in filter install info, filter should be before lift pump to allow water seperation in filter). The add on filter does trap water/rust that i never was able to detect from th OEM filter. I assume the water was going through the OEM fiter.

After I installed the 2nd filter , I would see a fuel pressure drop , ( never really checked it before mod's ) sometimes to ZERO under a hard pull.
Therefore I installed the 2nd lift pump with a switch for control.

When pressure drops, I turn on the Switch...

I drain the add on filter periodically, usually I get a 1/4 teaspoon of brownish water,
The add on lift pump , in series, allows flow through it with no power applied.

I also use the 2nd lift pump To purge air, after filter change,: Turn on Sw, 2nd lift pump pressurizes system.

Plus: I like gage and switches!!!!

qwestqaz, What did you use for the second filter? Stock or aftermarket?

Perma cool kit, from JEG'S catalog... kit was about 40 US and filters are 13 US,

Solid metal spin on 2 mc filter ( like an oil filter ) with a drain valve as part of the filter.
real easy to change..

Down side, only place I have found to get filters is the Jeg's catalog

I am returning an old post (because I haven´t seen it before now). This was very interesting conversation, but I would have a few guestions.:confused: If the stock lift pump fails to pressure the stock IP, it obviously does´nt cut it to a lets say a marine pump either, right? Has`nt anybody tryed the Dodge Ram`s pump? And what I red, It produces more pressure, does this hurt the IP?? or something. And could an ordinary gasoline engine hi volume pump be used with a regulator?(I`m new to diesels) I know the flow thru problem, when pump not running, but otherwise. Then the filters, why use orginal filter on top of engine and make it bigger, isnt there aftermarket filters that would flow better and would be easier to chance?(after being installed somewere else). Thanks for answers.

Some more pics for you here is the filter screen for the IP threaded into the IP body. I was helping another member out offline and shot these after we discussed possiblity of it being clogged, his truck is reacting like it has poor fuel supply. All other basic flow checks are satisfactory.

One of the things that got me to thinking about it is member did not know the plastic last ditch screen in bottom of fuel filter bowl was missing, I'll have to look and see if I can find pics of that. They sometimes get stuck in center of the old filter element and get tossed away, but it is supposed to be in the bottom of the filter bowl of the on engine mounted filter, make sure you don't throw yours away.

Pics of the on engine filter and plastic screen here http://www.dieselplace.com/forum/showthread.php?t=40783

Cool info, think mine is gone. It should be OK if the filter is clean and OK right? Here are some more pictures of some of the fittings on the IP http://dieselplace.com/forum/showthread.php?t=36541

TD,

Thanks for the post and info. I used this today for several things. First was to replace the fuel filter drain hose (which is out the side where the WIF boss is and curved back towards the front of the engine on my 1994) and the other was to consider doing this modification myself!

Would Kennedy's higher capacity lift pump be sufficient to pressurize the system to 2lbs on heavy acceleration? That is pretty much plug and play.

Was looking that direction myself, also running a test soon with a Cummins pump, only problem is Cummins pump isn't full flow thru on a fail; what I may do since I have it set up already is run dual pumps, OEM and Cummins pump, power the Cummins when I need the extra grunt, and run OEM in daily driver mode.

I visited a IP shop couple of weeks ago, and we ran some experiments on a flow bench, IP is mounted on the bench and run, output of distribution head is captured in a graduated chamber that measures pump output. What the higher lift pressure netted no so much more final delivery from the IP; but a more even distribution of delivery, where-in reading individual output captured per chamber was all 80mm, vs. avg of almost 80mm across the chambers at the lower supply pressure.

If you want to run a cummins pump, just buy a carter high output pump from summit. Pretty much same pump as cummins for half the price. Also, you can plumb in a tee in front of the lift pump and install a one way check valve. This way, if the cummins pump is off, fuel can be drawn around it instead of trying to suck through it. The check valve will prevent the pump from pushing fuel back to the tank when it is powered. I think I have seen some carter pumps that include the check valve and are listed as supplemental lift pumps or pusher pumps.;)

So what if i took a Mallory 110 GPH pump and put that on the truck? Would I start leaking a lot of fuel out of place that cannot hold the pressure?

So what if i took a Mallory 110 GPH pump and put that on the truck? Would I start leaking a lot of fuel out of place that cannot hold the pressure?

Chiago, use a pressure regulator so it doesn't overpower everything.

Actually this project is still on hiatus being away for work & Katrina recovery haven't allowed me time to finish the Cummins pump test portion, the OEM pump alone with opened up fittings has been night & day different in the way my truck performs.

I have a Cummins pump in hand; that was gifted to me for the test so I don't need to buy one, just a check valve, for most folks all that is required is the full flow fuel lines no high volume pump, look at pics IMO and from my on engine tests you just can't get proper GPM(volume) through the coffee stirrer sized tube GM plumbed these trucks with.

Heath has a higher delivery pump thru flow that is direct fit in the OEM pump's spot. Kennedy also has a very attractive after market thru flow kit as well that includes a relay to help with weak OPS design. One thing is I see as a detractor of the Cummins pump is it's lack of flow thru in event of pump failure, you will get a no flow condition, so you will need to either keep a OEM pump in parallel with the cummins, or replace with a aftermarket one that is flow through by design.

Tim,
What size are the threads on these fittings?
http://www.dieselplace.com/forum/attachment.php?attachmentid=7976&d=1125075126
Thanks.

New Barb end is .280" ID, and .187" ID for old barb fitting, I had my new one made special, I believe it is a 4 A/N straight thread OD is .430" across the threads, the new barb fitting goes into the filter on top of the IP, I also had a 3/4" socket turned down for clearance fit to get the IP inlet screen out, that the fitting threads into.

I'm wondering if another option would be to make a line with a fitting that would thread directly into the IP.

I recently did a vegetable oil conversion and while I was looking at all these parts I remember thinking how small and restrictive all of the orifices were. In my conversion I used a separate tank, lines, lift pump, fuel filter, etc... to get me to the IP. The lift pump everyone reccomended for the vo was the Walbro 6065. There were several other pumps mentioned but there was talk that too much pressure would kill the IP. Initially I installed the Napa version of the Walbro, it was not the same it was noisy and kept a constant pressure or at least tried. Plus it ran really hot because it built pressure driving at slow speeds. I pulled it off and added the Walbro and it made a big difference. First off it is a lot less noisy, second it seems to work as fast as it needs to. When I am idling you can hear it slow down and when I get on it, the Walbro delivers fuel faster. You can hear it speed up and slow down with fuel needs. On the Cummins people are using the stock lift pump for veggi and diesel but on the 6.5 the stock LP bites the dust in short order on veg. You can get a Walbro for about $85 and if I ever lose my IP on the diesel side I will install a Walbro in a second and I believe it is a good option for a high quality lift pump. BTW Turbine Doc, if anyone is interested I could email you the pics if you would post them. I'm not quite sure how to get them up.

Part II CR's version http://www.dieselplace.com/forum/showthread.php?t=75397

Did some convesrions http://www.sepinc.com/flowcalc.htm
Cummins flow in thread 11 GM flow
9 psi 260 pph = 30 gph 4 psi 115 pph = 13 gph
10 psi 242 pph= 28 gph 5 psi 94 pph = 11 gph
11 psi 217 pph = 25 gph 6 psi 10 pph = 10 gph
12 psi 184 pph = 21 gph
13 psi 146 pph = 17 gph
14 psi 115 pph = 13 gph
15 psi 92 pph = 11.7 gph

Flow test an injection pump on the test stand to check for total flow through the pump and the injectors to get an Idea as to how much fuel flows through the pump and injectors. I used a rebuilt DS4-5521 injection pump. Please note different rates can be obtained by various pumps due to wear and return rates back to the tank.
I used a flow meter calibrated in PPH* Liquid G. 0.81175 Visc. @ 95 degrees. using VISCOR test fluid (about the same as diesel)

3000 rpm----70mm 3/stroke------165 PPH ----OEM Calibration
3400 " ------50mm----" --------140-"
3400 " ------20mm----"---------110-"

3000 "------80mm---- " --------180 -''-Maximum Pump output
3400 "------82mm-----"--------192--"------"-----"-----"

GM Supply pump
4PSI - 115PPH
5PSI - 94PPH - (desired pressure)
6PSI - 88PPH

At high full load demands the stock unit falls short. When the flow rate exceeds 94PPH the pressure will fall off.

*PPH > Pounds Per Hour ( pounds of fuel flowing through system in an hour)

Not sure i'm understanding the properly. So for my 92mm pump i will require a LP to put out about 225-250 PPH at 5+ psi? :help2:

I think so CR if I read the data correctly, you need a bigger lift pump to make 92mm capable of delivering it, Lyndon how do the numbers DP posed on his bench correspond to feed required to make 92mm delivery

I was looking at these today, delivery pressure seems to be low though at higher delivery rates.

Local shop in town carryies them for a direct replacement for John Deere lift pumps in the lesser model.

http://www.pegasusautoracing.com/productdetails.asp?RecId=86

Figures can be confusing. "Rigger" if you need a Cummins supply pump and will use it, I'll send you one.

Dang freight is going to kill me, but it's just money.

Is it here yet? Is it here yet? Is it here yet?

How does one plumb it in? Use the existing wiring to run it, is the pressure of the pump to much for anything ahead of it?

Is it here yet? Is it here yet? Is it here yet?

It's already there. Opps, the way back machine. Dang, I forgot the address now we're screwed. Well, I ain't going to send another one to get lost. PM me your address and how it's supposed to cross the border and I'll send it. It'll work fine.

Pump dissection photos phots of a GM pump a Katrina submerged pump, and a Cummins pump

More

I always wondered what was inside one of those pumps. What fails on this design? The valves?

The one I dissected just quit pumping after about 2 minutes of pumping, looks to be a bad tron thingy notice discoloration around the resistors on the brain circuit board, also the coil itself going open. the pump cools itself with flow, kinda reminiscent of the PMD needing it's tron components kept cool

mechanically I would suspect a piece of crud keeping one of the the rubber flappers held open, a hole in diaphragm, a worn seat, a spring weakening, or swimming in salt water like the Katrina pump did after being submerged 4 hours in salt water on my shop's lower shelf

So, how do they get different flow rates with this pump? Plunger size or electronics? After seeing the insides of that pump, I may have to reconsider my fuel system upgrade design.

nice work whens the next mod going in? lol

I talked to a friend of mine who knows a lot about this sort of stuff. He has a race boat with a much modified big block Chevy with Lucas timed injection - very impressive with 8 injectors sticking up by the way. Anyway, he suggested several methods.

First, he says you need check valves on both pumps. If the vane pump fails, he says the stock pump may be able to pump past the vanes in the reverse direction and if that happens will not pump sufficient flow or pressure to the injection pump.

Second, he suggested to forget the check valves and to use a 2 way valve on the output side of the pumps. You would also need a 2 way switch to turn off/on the pump you need. Basically you turn the valve & switch to the pump you are using and the other one will just sit there. I suppose you could get an electric valve and have everything wired into one switch.

I'm thinking of using the Cummins pump and stock pump in parallel with check valves. If I understand this correctly, the Cummins pump will run all the time and the stock pump should sense the pressure and probably not run. Should the Cummins pump fail, the stock pump would then come on and supply fuel to the inj pump. Sound right?

That's pretty close to the way I'm going to do it Bobby, GM pump will be normal supply and Cummins for dyno/tow and a switch to shut off either pumps power. If you remember I have LEDs to monitor pump power on , a fuel lift pressure gauge which you may or may not have seen during our brief visit last week. Good thought on 2 checks, it is possible if vanes stop the right way you could back flow through it as well.

A 2 way valve would worry me some as all eggs in 1 basket if it doesn't shift over and you get no fuel, check valves would be automatic mechanical devices not needing anything other than pump output or IP suction to open them if a pump failed to deliver.

Now - that's what I would call a real gearhead's tailgate party..........

Comparing pump output between brands would be difficult, but pump-to-pump by one oem -

They are flowthru, with electronic switching, as mechanical switch contacts could ignite the fuel.

Increased output requires larger coil, either diameter or length, or both, and possible increased shuttle length.

As you can see, in those pumps, the coil form allows for more windings, even with larger wire size to decrease the resistance\turn

Within oem type, the weight of the pump, if not the length and\or diameter, will usually indicate increased output.

The rotary roller or vane pumps get wider cross-sectional pumping elements, or larger diameter, and\or more pumping sections, stacked.

The in-tank GM and Ford pumps are flow-thru rotary vane type - single element for carbureted - 7psi, dual for throttle-body - 14psi, and multiple elements for increased pressure requirements of port-FI - 35psi and up.
They can be distinguished by length and slight increase in diameter.

The rotary-type can also produce greater output by increased operational rpm, so the aftermarket versiions - Holley, Carter, and etc - are more difficult to distinguish lo and hi output pumps by size comparison.

I'm working on modifying the inlet and outlet on the Cummins pump now but was wonder about something. How on earth did you drill out the in/out without filling the bottom end of the pump full of filings???

Added a pic

I havent touched the Cummins pump other than to make barbed fittings for it, but looking at your pic I'd drill with open end down , maybe have the bit lubed up with grease to catch the small pieces, and then to a good alcohol flush, or spray contact cleaner when finished. your 5 micron filter on the engine should catch anything you miss, drill shavings will be a lot bigger than 5 micron.

Whats the spring and ball setup in that hole all about? There's another on the output side also.

Probably check valves I havent looked that close at mine to even kow if they are in there, I'll look at mine if they are checks I won't have to fit my pump with an extra one, I was concerned with reverse flow when pump was not running may not be a problem afterall, I knew the GM pump had one but it is rubber and I didn't know if it could handle higher pressure of the Cummins pump. I may have to check with DP next time I'm over his way and run a little experiment

here is my pump that will be intalled next week hopefully.:)

its a 110 GPH Mallory pump, should do the trick i think, have two laying around so maybe I will do two in parrallel to make sure I will ALWAYS have enough fuel;)

Can someone say overkill how many psi it put out, and is it Diesel fuel compatible,

in all seriousness if it deadheads does it shut off and self pressure regulate, or are you routing a return back to suction side of pump if going in to recirc bypass fuel, any thought it might overheat fuel in a consistent recirc mode, not criticizing just making sure you've considered possibility bigger (this big) might not be necessary.

Guess before I thow stones I don't know GPH of a Cummins but I don't think it's that high

Don't forget to service that neoprene hose between the filter and the Inj Pump - it's been down in that hot valley for hundreds of thou miles, and the 'seasoned' rubber will not exhibit much of the 'live' quality it should have to seal any increased pressure and volume.

Hard hose leaks fuel......

Can someone say overkill how many psi it put out, and is it Diesel fuel compatible,

in all seriousness if it deadheads does it shut off and self pressure regulate, or are you routing a return back to suction side of pump if going in to recirc bypass fuel, any thought it might overheat fuel in a consistent recirc mode, not criticizing just making sure you've considered possibility bigger (this big) might not be necessary.

Guess before I thow stones I don't know GPH of a Cummins but I don't think it's that high

Please don't shoot me if I'm wrong but I think the Dodge guys said that this is what the stock lift pump is for them.

http://store.summitracing.com/partdetail.asp?autofilter=1&part=CRT%2DP4070&N=115&autoview=sku

Thanks Guy that looks like the pump I have waiting to be installed, GM pump is a wussily 15 gph, which is okay for 90% of my driving especially since my opening up of the fuel ports & lines, my Cummins will be manually controlled so I can switch it on/off for HD towing and dyno days, I think dual pumps 1 large, & 1 small might be a good fit I'll monitor fuel temp with scan tool to see if recirc is generating too much heat, I was also going to try 2 small in parallel but Katrina submerged 1, and the other (one in pics disassembled) quit on test run.

Please don't shoot me if I'm wrong but I think the Dodge guys said that this is what the stock lift pump is for them.

http://store.summitracing.com/partdetail.asp?autofilter=1&part=CRT%2DP4070&N=115&autoview=sku

That pump is for gas only according to the description and only has a max pressure of 6 PSI.

Try a Holley Red, works great.

I picked up the metric fittings i needed today, they just need some customizing of course... lol. Hopefully will save having to drill out the pump body.

CR, which Carter is it?

Suppose to be the Cumins pump, same as TD's. Heres the only number on it.
#13985H19A

I should have caught it earlier, fittings aren't metric, the are straight thread A/N fittings, #4 AN I think, maybe #6 same as IP inlet fitting, I see in the other thread you went to 1/4" NPT barb fittings

I should have caught it earlier, fittings aren't metric, the are straight thread A/N fittings, #4 AN I think, maybe #6 same as IP inlet fitting, I see in the other thread you went to 1/4" NPT barb fittings

I took the pump in with me, don't recall the type of fitting we got but it seals with an 'O' ring against the pump body, but while drilling 1 out for 1/4" ID i kinda wasted it. So i said to hell with it and drilled and tapped the body for 1/4" npt.

You should see the monster i've built...:lol:

And now because inquiring minds want to know...
Heres a pic.

CR, you crack me up man, LOL, holy GOD!!!!

I have to say, never have I seen "sewer pipe" for fuel line, this is certainly a 1st for me.

It looks schweeeet.:ro)

You must have been a plumber somewhere in your past vast montage of skills.

That looks like a Carter electric supply pump. Are you going to monitor the pressure? Pressure may be higher than expected when compounding two fuel pumps in series.

But we all know how you can compound your problems.:)

CR, you crack me up man, LOL, holy GOD!!!!

I have to say, never have I seen "sewer pipe" for fuel line, this is certainly a 1st for me.

You get what you can locally for testing purposes. The cheaper the better. If all goes well things will likely change.

I have seen it used before.

A boat I ran for several years had it from the tank to the filters. Probably common on boats. There were some major problems. Likely caused by salt water.

The plumbing was under the floorboards and an elbow fitting got a hole in it.

1200 gallons of diesel in the builge ain't pretty.

Has anyone used one of these?

http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2DG3136&N=700+400304+4294925239+4294836965+115&autoview=sku

5 or 6 years ago, I put one of these(I think it was this one, it was a summit brand anyway) on one of my John Deere combines to replace the mechanical lift pump that mounted to the side of the IP. I mounted it below the fuel tank where its orriginal electric was. With this pump I replaced the factory electric, IP driven mechanical and hand prime pump. It now runs and starts better than ever and is a breeze to change filters(just turn key on, but be ready only takes a couple seconds), best of all prolly saved me a thousand dollars or so not having to buy a new IP pump or IP pump housing and having my IP guts put in it. It prolly has a 1000 hours on it now, no leaks, no problems.

I think I'll try one my truck, if I get energetic.

Where you gonna put it?

Gonna push fuel into the filter or pull it through?

Will you replace the OEM lift pump or just use both?

When it fails will fuel flow around or through it?

If it fails and fuel won't bypass the engine just stops, correct? It won't damage anything, will it?

If this is the case, I'm just going to buy 2 pumps. It wouldn't take me long to swap pumps if it quit, and I won't have to wonder if the pump is working or not.

Bill

The one it comes with is flow on fail and you won't run out of fuel, which could be a bit of a problem with a diesel. Also the truck will still operate on the original failed pump. It's good to have a fuel pressure gauge so you now when it fails.

You just might consider another alternative that will have flow on fail.

Sorry, the one I used before was different, it looked like this,

32105

and I'm pretty sure it pumped 25psi instead of 14psi. But any way I was just suggesting what I had used with diesel before with success.

David, I would mount it on the frame, similar to original. I might mount a dual setup as a backup, but really I would not be worried running just the single, as the one summit already outlasted all the pumps combined on my 92, running in 100degree texas heat 8-10hours a day straight, with no problems.

Cool!

if you tap too deep you will ruin the filter housing (YOU have been warned).

TD - I plan on doing this mod shortly....any more insight into this, or will I figure it out on my own? I have 2 filter housings I want to do this to and I don't want to screw one of them up if possible....

I would love it if Heath or Kennedy or SS would fabricate up 10 of these, with a fitting for the IP and a couple of hoses cut to length. Take my filter housing as a core.

I think they could sell a bunch of them, and I'd buy one today. I just don't have the time, inclination or proper shop for that sort of mod.

what about ditching the factory filter housing assembly and going with a filter assembly that already has the larger ports? All that you have to do is get the 12mm threaded fitting and the hose/tube to make the connection.

Ok....I have been to the hardware store and I am slightly confused...

When you guys say you use 1/4" barbs are you talking 1/4" ID or OD of the barb?

I looked at some 1/4" hose and it was pretty tiny stuff....what size hose are you using? Is is measured by ID or OD?

Is this the right fitting to go into the housing?

http://www.amazon.com/1-4x1-4MPT-Barb-Insert/dp/B000BPDIBM/ref=sr_1_180/002-1180883-1348014?ie=UTF8&s=hi&qid=1173314745&sr=1-180

Is this the right fitting for the IP?

http://www.cleaningcomponent.it/immagini/prodotti/caldaiebig/Portagomma1-4.jpg

I have my truck plumbed with high pressure rubber from tank to filter, and this stuff was expensive and overkill. I used 3/8 to feed and 5/16 to return, this size slipped over the factory steel lines quite well. I'm gonna guess that your lookin' for 1/4" ID fitting's. I could be wrong but 1/4" OD seems pretty small.

My fittings were custom machined, to be same ID as the fuel line, which is about 5/16", I'm running 3/8" OD fuel line that slips over the steel line from the tank to the new barb on the IP. Hardware stores have the 1/4" OD barb, which is bigger than the factory fitting but not quite as large as the one I had custom built.

As for earlier question, about doing away with factory filter mgr, getting rid of that eliminates the WIF sensor, and heater element as well, Racor sells a replacement body with both WIF and heater element, I guess it is possible to adapt them to work with the GM control and alarm if you don't want to eliminate those.

Ok....I have been to the hardware store and I am slightly confused...

When you guys say you use 1/4" barbs are you talking 1/4" ID or OD of the barb?

I looked at some 1/4" hose and it was pretty tiny stuff....what size hose are you using? Is is measured by ID or OD?

I fell victim to this myself , folks you have to read through the whole post sometimes to get max benefit, I forgot I had posted some sizing info, post 30 this thread has ID measurements

I read the whole post a few times....then I looked at the hose at the store and thought that something was wrong somewhere....I'll figure it out....

Pipe is measured inside diameter

Tubing is measured outside diameter

Hose is measured inside diameter

Tires are measured inside diameter and outside diameter

Integrity is the measure of a man

Tubing is measured outside diameter

Hose is measured inside diameter



That was probably the issue....

Pipe is measured inside diameter

Tubing is measured outside diameter

Hose is measured inside diameter

Tires are measured inside diameter and outside diameter

Integrity is the measure of a man

):h

Here is all the specs. on the Delphi lift pumps that fit our trucks. http://dieselaftermarket.delphi.com/NR/rdonlyres/9CA39F3C-C95E-440D-908E-CCD62303652E/0/CatalogDDCU103BW.pdf Go to page 65. The application guide is earlier in the PDF.

Awrite - you guys have forced me to get my hands dirty, on this, so here's whatcha get..........

DS4 inlet fitting is standard 1/4" tubing, 0.190" id, threads are standard 1/4" compression-fitting, as sold by Swagelok - stainless is best - available is a 3/8"male compression to 1/4" female compression fitting, screws right into the filter\screen assy, use the original silicone o'ring to seal as oem - fitting may safely be counter-drilled to 0.250" i.d. - maybe larger..... feelin' lucky, punk?...............

The 1/4" Swagelok fitting is, of course, 1/2" hex, smaller than the Stanadyne fitting hex.

Screws inta the screen-filter\regulator assy, where there are 4@ 0.125" dia orifices in the case behind the screen - these may safely be counter-drilled to 0.136", or drill 2 more 0.125" orifices - any more drillin', and it'd be 'bout as dependable as brittany..................

Ennybody do the math on the original 4x port and increased 4x port effective diameter or 6x port increase.....huh.........huh.....ennybody?

Clean out the shavings, de-burr the orifices, install yer screen over it's o'ring, install the modified assembly, install the ESO solenoid, and yer good to go.

'Course, this ain't gonna help a bit if ya got a bunch of 2-micron filters up-stream of it, retardin' flow and givin' false impression of adequate pressure.

You'll need yer gage tee'd into the new 3/8" hose between the filter cannister and the DS4 to know whatcha really got, eh?

Now can I clean up?

Hey chrisk1500 are you following this? Cause it's way over my head! Just send me the parts and I'll bolt them on. :D

Dave

going to 1/4" i.d. is a 173% improvement over stock inlet diameter

Hey chrisk1500 are you following this? Cause it's way over my head! Just send me the parts and I'll bolt them on. :D

Dave

;)

We can add some pictures to gmctd´s good explanation.
Click the letters in blue, and there are som pictures for you.

http://www.v8dieseltech.net/gm65td/fuel/new_e.htm

We can add some pictures to gmctd´s good explanation.
Click the letters in blue, and there are som pictures for you.

http://www.v8dieseltech.net/gm65td/fuel/new_e.htm

I have read this a few times....thanks again for posting it!!!

I'm looking to find one locally; a store bought one that meets dimensions of my machined one, supposedly the hydraulic shop here has (30) of them , 1/4" pipe x 3/8" hose barbs, if thru hole is .280" like mine I'll get a few as my Burb hasn't been converted yet either, I found one on the net that is very close to my dimensions for flow pn 4-1MPHC-6 http://www.tylok.com/index.cfm?action=fitCatalog&line=8&cat=1MPHC

Cool link, GMC 2500 - thanks.

One exception, tho - the four original 0.125" dia orifices = 1/2" dia, still larger than the modified 3/8" fitting.

It's probably not necessary to increase the size of those - increasing inlet dia from 0.190" dia to 0.250" or 0.280" id should be sufficient.

Figger 80mm3 flow rate @ 3600rpm x 60min = ?gph

Remember - 15gph x 60mph = 4mpg

Yes gmctd thats correct.
But..
How much resistance are there in the small filter?
Why not open up when you work the truck?

Not disagreeing with that - but for those without the facilities, the inlet substitution will suffice.

Dug deep into my memory for the formula for surface area of a circle(piR²). The original .125" orifice holes equal a total of .049" sq of surface area. The original 1/4" fitting equals... drum roll... .049"². Open up the orifice holes to .136" and you get .056"² of surface area. A 3/8" fitting has .110"² of surface area. The 4 orifice holes need to be around .180" to equal the input of a 3/8" hose. 6 .150 holes will get you closer to the area of a 3/8 hose.

I haven't done math like this in 20 years, I could be wrong.

Correct, with exception - the original 1/4" fitting is 0.190" dia, for 0.028" area

Increasing the inlet to 0.250" will increase the area to .049", so the simplest upgrade - replace the fitting - will be a worthwhile improvement, matching the area of the four 0.125" screen orifices.

For clarification - draw four circles in a vertical column on a ruled paper , one line for each circle, each representing 0.125"

Draw a circle around those four, the diameter enclosing them representing a 0.500" circle - 4 x 0.125 = 0.500

You can see how 4 x 0.125" orifices may fit within a 0.500" orifice, but cannot equal the area

And thanks for the math, B Lake

For any canucks doing this mod I will post part numbers from Princess Auto for the fittings required.....I am following the same method as Rigger did...

Mods - I don't think I am stepping on any toes by posting part numbers and prices because no other supporting vendor (that I know of) is in direct competition with the local hardware store....please edit as necessary...

You will need....

2 hose barbs - 3/8" I.D. x 1/4" NPT(male).....PN 0431643 $2.19 pr

1 o-ring boss x NPT swivel adapter - 4 ORBM x 1/4" NPT(female)...PN 129221 $3.19 each

??? ft of fuel line - 3/8" I.D........PN 2461416 $1.59 ft

2 1/2" hose clamps - PN ??????? $.??

Here are some pics...

Screws inta the screen-filter\regulator assy, where there are 4@ 0.125" dia orifices in the case behind the screen - these may safely be counter-drilled to 0.136", or drill 2 more 0.125" orifices - any more drillin', and it'd be 'bout as dependable as brittany..................



So you are saying that a 1/8" drill bit is what was used to get the holes to OEM spec correct? (1/8 = .125")...

You also say that they can be bored to .136".....

Would I be safe if I used a 9/64" drill bit (.140") or would I be encroaching into dangerous territory?....

No - you can drill two more 0.125" holes for six 0.125" orifices, or open the four oem 0.128" orifices up to 0.136".

Any larger than that and you hit the threaded area for the housing pressure by-pass regulator - didn't even wanna do that.

I didn't bother with that, because the inlet increase to 0.250" equals the area of the four oem orifices - if you go to 0.280" or 0.290" on the inlet you may want to try increasing the orifice area.

Maybe you can get some inlet assy's from yer local IP shop - let you see what is required B4 pulling your own - or might even PM Diesel Pro for some equitable assistance in that procurement, eh?

Decisions decisions.....the American says it is ok to leave the holes alone...the European says the holes MUST be enlarged....oh what is a Canadian to do???...eh...

I think they're plotting against us.....trying to confuse us. The next thing you know they'll be distracting us with beer and hockey and then it's all over! :D

Dave (loves beer and hockey) :)

'mornin, boys ... somebody mention beer and hockey? LOL

I think it's a point of diminishing returns, Chris ... you can only get so much fuel through a hole, so the 4 x 1/8" holes should handle all you can get through the inlet. The only other thing to consider is pressure head - if the holes are even slightly bigger, there will be a pressure reduction in the filter body. Darned if I know where the next restriction is, or what the pump internal pressure would then be, but that reduction could let things flow a little easier.

Think of a waiting room with a single door in and single door out - once the room is full, if you open both doors, people can come in and go out at the same speed, so the room will always be full. If you make the exit door into DOUBLE doors, the room has a chance to empty because more people can leave than can enter.

I think I'd leave it alone, and let input = output.

The facts, ma'm - just the facts....................

I just had another look at the fitting....

gmctd - you of course are 100% correct....you cannot make the holes any larger (taller that is) without cutting into threads on top or on the bottom....

There is a ring in which the holes are drilled that restricts the height of the holes....

Sorry Dave, I think I will take the advice on here and leave well enough alone with those inlet holes...

The holes can always be bored out at a later date if required....

Works for me man.

I always knew those Euro Dude were a little crazy.....drilling out .125 holes with minimal clearance for little gain......What are they thinking?!? :D

I did someone say beer and hockey?:)

Dave

Sniff... Beer? Hockey??

I didn't bore out the holes either... It looked like you would be left with nowhere near enough meat for the threads to work.

Is the fitting that screws into the IP screen assembly 4-AN threaded? Tim said it was, but not with enough conviction for me to order one. thanks- Joi

Fittings in the hydraulic section of a farm supplies store will have the right threads....the ones you need are #4 ORBM....I have no idea what that means in regards to AN threads....

bah...the yuppies drove out all the farm supply stores around here. thanks for the size, Chris. -Joi

The size and threads are SAE 7/16-20, standard fine.

going back to one of the earlier posts, Tim mentioned 1/4" pipe thread (for 3/8" hose barb) So, yesterday, I went to the hardware store looking for said thread size. I found it, and clearly there was no way it was going to fit into the IP...guess those would be for the filter housing.

I bought an 1/8 x 6 brass nipple, a brass adaptor 1/8 pipe to 3/8 hose barb (made this with 2 pieces). All fittings have minimum 1/4" ID.


Granted, the 6" nipple needs to be cut down and I have to add a 7/16" nut and clean out a groove for the o-ring. Is there any reason why I shouldn't make this mod with 3/8" hose? Can the filter housing be tapped for a standard 3/8" hose barb?

This isn't so much because bigger is always better (5" cross-over coming next:rolleyes: ) but this is all I could find.

I will be using 3/8" hose as well....

The fittings I used for the housing and the IP are 3/8" x 1/4" NPT as you can see in my pics....

Mine wont be the prettiest, but as long as it flows fuel and doesn't leak, I think I'll be ok with it.

x2

The beast has been fed!

It was a pretty straightforward surgery....both housings had a full recovery....

Now I just need a reflash and an intercooler to reap the full benefits...

'way to go, Chris! You made THAT look pretty easy!

Do as you wish..
You guys know best, so I've got no right to interfere.

But tell me the results you get..
...and maybe I'll tell you the results I got from drilling like GMC2500 said =)

Do as you wish..
You guys know best, so I've got no right to interfere.

But tell me the results you get..
...and maybe I'll tell you the results I got from drilling like GMC2500 said =)

I would be happy to share my results....what exactly are you looking for? Fuel psi at given ranges? I would have to find a pressure tester....and I don't have any pre-mod numbers to compare to...

Ran with a .280" ID feed the beast fitting on the IP on a test bench (fitting only) no holes drilled in regulator housing test stand requesting for 99mm delivery in manual mode, 10psi lift pump pressure, housing pressure was up about 20psi IIRC(need to write this stuff down) 160psi from 140 that was set earlier with stock IP inlet fitting, & slightly higher final delivery volume most cyls 78-80mm, several 81 & 82mm, with stock fitting avg delivery also about 80 but more in 77-80 range, and fewer @ 81. May also do the drilled fitting for grins as well later.

Sorry if it has already been asked: Why not replace the stock filter housing with a `remote mounted` filter?

Remote mounted would keep the fuel cooler, and the filter elements for the stock filters are rather expensive. Only problem I can see is not having the heating element the stock filter probably has, and the `water in fuel` light coming on. But what is the heating element in the filter actually needed for? If the fuel gels, that heater won`t help it.

Since I still have this one --- http://dieselplace.com/forum/attachment.php?attachmentid=867&d=1104507217 --- and since I still need to improve on my LP replacement, I might put it in instead of the stock filter.

I don't know what I was looking at, but this whole time, I thought that Tim modified the fuel filter housing inlet as well. Looking back at the original post, I see that it's still the factory inlet ( I got curious when i didn't see an inlet mod in Chris' pics).

Tim,
What made you decide to keep the factory inlet? Is there internal restriction that would defeat the purpose of adding a 3/8" hose barb there?

thanks -Joi

Availability of rest of the parts to meet need to get it back on road & more work than necessary as I did not consider .030 delta on factory inlet (.250") vs (.280") of custom IP fitting & 3/8" OD barb I installed on the outlet to be a big issue, and at time I only had 1 (.280") custom fitting, I have had 2 more fittings made so I have 3 now, filter outlet & IP inlet fittings were IMO the major restictions. I will be doing a relocation of filter mgr (easier to maintain/observe) and will swap the inlet & outlet fittings to also be .280" ID when I relocate filter.

Lee in answer to earlier question, I think the heater does serve some benefit to those of us in moderate climates that don't get very cold, plus I like the WIF sensor. As far as elements go, since Installing the Racor 10 micron on frame rail, I'm now going on year 3 of the factory 5 micron filter, plus with the DP switches on both Racor & OEM, and not alarm condition as of yet, I'm not going to have to change filters until they need to be changed, vs an arbitrary time/mileage requirement that may have me change a healthy filter prematurely.

Great info, Tim. thankyou! :thumb:

Thanks to chrisk1500 for doing the work (tapping housing and finding making fitting for IP).

I finished the job today...finally. It was not without it's challenges. The housing he sent me had a different drain outlet. Mine came straight out beside the outlet to the IP. The one he sent me came out the side and did a 90* bend (like the one in his pic at the top of the page). Because of this difference I had to extend the drain hose so I could get it over the outlet.

I also discovered (after putting everything back together) that I damaged the inlet hose when I was prying it off the housing. It leaked when I was trying to bleed the housing. I had to put in a new piece of hose from the main supply to the housing.

Working on these housings is not for the faint of hard. If you have hands like a bunch of bananas and can't kneel ontop of an engine, don't even bother trying! :)

So after all was said and done I did not see any change in fuel pressure at idle. Still 5 psi at idle. I haven't checked while accelerating. I only went for a short test drive after finishing the work, so the seat of the pants dyno didn't get much of a chance either.

I'll report back after a real test drive and if I get any psi numbers while under load.
Dave

The 6.5 fuel pressure drops off quite a bit under extreme load due to the weak supply pump.

I was hoping to overcome that with the opened up outlet from the housing and inlet to the IP. Maybe I still need a stronger LP too.

Dave

FYI - you could put sewer pipe in there and the lift pump will only put out designed pressure, particularly at idle, where supply exceeds demand - 5psi and 15gal\hr

Use a pump that can supply 5psi\30gph at idle, and it should meet your expectations at higher demand - 10psi\30gph is even better

This mod is for increased flow at higher demand, but will not increase pressure from a low-volume 5psi pump, where demand rate exceeds supply flow

I hear ya. I wish I would have got my act together and tested PSI under load with the stock set up so I could see if there was a change after this mod. I'm going to go out this morning and get some cheap hose to run from the T-Valve to my pressure gauge in the cab so I can check the PSI while acclerating.

Dave

Numbers I posted earlier for were with a fairly new/healthy stock lift pump, vs a fresh just installed Heath H/O pump, I'm still not happy with delivery under load so I'll be looking to a Kennedy pump becasue of it's centrifugal flow thru on fail design or 2nd OEM style lift pump in parallel.

Something to consider that I've added to mine is a power on LED that lets me know lift pump is getting power from OPS, I also agree with earlier recommendation to monitor lift pressure, as a good pump at idle may be weak under load and you won't know it without gauge.

gmctd - what LP are you using? I am under the impression that you have a 3/8" IP supply line as well....correct?

I R&D'ed the mod, just not installed, never had the starving problem with that big hoss - I had replaced the oem LP with the higher output version, 905?

Three LP's between '93-'98, whichever one was highest - slept some since then, so it's all gone foggy.

But, it never starved for fuel, not even when it sheared the flexplate off at the hub at 3500rpm 1st to second, or when it split and crumbled the second sprag clutch, 1st to second at 3500rpm.

So I got to thinking today. Now I'm no genious, especially when it comes to some of these mathematical formulas used to figure certain things out.

When testing PSI by attaching the pressure gauge to the end of the drain tube, is it going to read anything different after making this modification?

Nothing has changed with the drain tube. Will opening up the path from the housing to the IP somehow change the pressure to the drain? I could see how adding a higher output LP would, but I'm not sure about by just opening up the outlet from the hosing and fitting on the IP.

I guess to get a true measurement I would have to tap in between the housing and the IP.

Whaddya think?

Dave

Only time you'll see a difference is under full power - idle is sorta static, comparatively

Dave, if your mod helped you will see less pressure now testing @ the filter under load, because you removed a restriction and your injector pump is taking more of the volume of fuel lowering system pressure. Hope that made sense.

Well today I finally got around to running a tube from the T-Valve drain into the cab with my pressure gauge on the other end.

5 psi @ idle, never dropped below 2 psi under the heaviest of heavy accleration as soon as the tranny would shift and speed stabilized it would climb back up again. 4 psi cruising at 60 mph 1800 rpm. I really wish I would have done this with my stock housing. Has anyone?

Good enough you think or is more alway better? ;)

Something I did notice now that I've had a chance to drive it a little more. Definitely more responsive. I always had a slight fuel knock/rattle when acclerating, not even acclerating hard, until the turbo would spool up. Just that second or so before the boost would start to come up. That seems to be pretty much gone.

Now I just have to get my damn intercooler installed so I can take advantage of the 15+ psi of boost that she'll produce. :)

Dave

Good enuf for now, but tomorrow is another day, always needing more :D

I've got something else in works will add more to this subject when I get finished.

Well today I finally got around to running a tube from the T-Valve drain into the cab with my pressure gauge on the other end.

5 psi @ idle, never dropped below 2 psi under the heaviest of heavy accleration as soon as the tranny would shift and speed stabilized it would climb back up again. 4 psi cruising at 60 mph 1800 rpm. I really wish I would have done this with my stock housing. Has anyone?

Good enough you think or is more alway better? ;)

Something I did notice now that I've had a chance to drive it a little more. Definitely more responsive. I always had a slight fuel knock/rattle when acclerating, not even acclerating hard, until the turbo would spool up. Just that second or so before the boost would start to come up. That seems to be pretty much gone.

Now I just have to get my damn intercooler installed so I can take advantage of the 15+ psi of boost that she'll produce. :)

Dave


I've been wantin' to put my gauge inside to see what my pressure is at while drivin' but I keep forgettin' to do it. I get 5psi at idle but that is all I know and my LP is old and I'm curious. I will run it inside and post my stock housin' numbers for ya...and me too.

Sounds good. I just picked up some 1/4" ID clear tubing at TSC (.99 cents per metre) and ran it through the hole in the firewall where all my gauge wires etc. run through.

It will be interesting to see what number you get.

Dave

I ran back out to the shop after supper and plumbed it thru the firewall.

5 psi at idle
4 psi cruisin' at any speed
3 psi under hard acceleration

Apparently my LP is doin' better than I thought :)

My gauge is in 1 pound increments, each of those numbers were dead on. So there ya go Dave!

Oh, one more thing, Go Sens Go!!! :D

Hmm, you must have a strong lift pump. Must be one of those 10-12 psi rated pumps vs. the 6-8 psi. Might have to get myself a Heath pump or one of those Delphis that are rated at higher psi.

Maybe this is the year the Sens get past the first round. :) I suppose I shouldn't talk, they're doing better than the Leafs. :( ;)

Dave

yep sens are playin' hockey, leafs are waitin' for it to quit snowin' so they can play golf, friggin' weather!

I don't know about my LP, maybe someone changed it to a higher output before I got it. I dunno!

Hey Dave12,
Is there any chance we could get some pictures of the fuel gauge installation? Also, what is the part number for the fuel filter screen? Thanks for the help!!!!!:)

The gauge install was just temporary. Clear plastic tubing ran from the T-Valve through the firewall attacted to the head of my Vac/Pressure gauge. Start the truck, open the T-Valve and drive.

Filter screen part number is Stanadyne 29244 only available at Stanadyne dealer but apparently not all of them can get them or will try.

Dave

hmmm..... 8 PSI @ 100 gph...... yeeeeah.... what? only $103? well ok then........

P4600HP

Scrufdog, who's part # is that?

I just had to replace the LP yesterday. The IP pulls a pretty good vacuum.
I went with a Napa (carter) LP that's rated 10-14 psi and 25 GPH. The thamn ding cost me $94. Resulting fuel pressure at idle = 3.5psi measured at the stocpock. This is exactly what I've had with every LP that I've had in the burb. Oh well

Remember - your lp is flow-thru when fail so you can get home.

Positive displacement pumps - roller, vane, gear, etc - will dump you at fail.

Found this bit of trivia this morning while searching for a pn I had lost from a Cummins site

The new fuel lift pumps, Part Numbers 4932707(12 VDC) and Part Number 4932708(24 VDC), obsolete and supercede the previous fuel lift pumps (Part Numbers 3990105 and 3990106). The new fuel lift pumps have an internal bypass circuit in the rotor housing that allows fuel to be drawn, with less restriction, from the fuel tank to the injection pump in the event of an inoperable fuel lift pump.

Okay I've been looking for a good deal on forementioned pumps, Cummins guys still ain't impressed with "new design" (or any vane pump for that matter) Walbro pump is what many are replacing em with, once I find a good number for a Walbro pump I'll post it

the one I posted was a Carter part number thats popular with Cummins guys.

FWIW I asked about Carter & Delphi equivalent to shop I was talking to via email & phone "I don't like vane pumps period even the Carter one" was reply,

Anyone have any new number or info on this?
I was thinking on doing this myself while I have everything apart.

I was also thinking on moving/replacing my filter housing to a different location also. I just wish they would of came up with a see through bottom.

What kind of numbers are you looking for Joe? I did mine about a month ago. No big noticealbe change in performance but I guess every little bit to help the fuel flow better. chrisk1500 did all the work for me, I just did the install. With things apart like you have, it's a 5 minute job.

If you're good with a drill and tap then it should be a breeze to modify the housing. Modifying the pump is simply a matter of changing the fitting which I'm sure Chris could give you some specs on that, if it's not already listed in this thread.

Dave

Hey Dave,
Any word on those filter screens ? ..............PLEASE Don't forget me.

Thanks, Louis

What kind of numbers are you looking for Joe? I did mine about a month ago. No big noticealbe change in performance but I guess every little bit to help the fuel flow better. chrisk1500 did all the work for me, I just did the install. With things apart like you have, it's a 5 minute job.

If you're good with a drill and tap then it should be a breeze to modify the housing. Modifying the pump is simply a matter of changing the fitting which I'm sure Chris could give you some specs on that, if it's not already listed in this thread.

Dave

Yes I read all the posts till I got lost because of all the numbers and tings mentioned. I was just wondering if it is worth the time? I already maintain 3 psi under wot and bounces back to 8 psi. I will probably jump on this since who knows what the future will hold. More fuel more power...lol You know how it goes.

I've got a test pump coming Walbro in-line flow thru 45 gph @ 8psi free flow self regulating, unfortunately I'll be out of town when it gets here, once I get some data like p/ns & run data I'll post back here with it.

J/K I now run 0 psi @ hard WOT even with the Heath H/O pump since opening the 4 holes in the transfer reg fitting to 5/32" or .15625" for .625" total possible area to flow. It recovers pretty quickly back to 2-3 psi WOT but I can run it out of fuel if I ain't careful.

Before I did my intake swap I had not drilled open the transfer regulator fitting/screen holes, I was in easy access to it with intake off and decided to see what full flow fuel inlet would do, possibly a slight increase to acceleration but not really sure anything definative over just opening up other fittings, EGT is somewhat higher, meaning a small change to fuel I think, but IATs are starting to be higher with onset of summer as well.

For any canucks doing this mod I will post part numbers from Princess Auto for the fittings required.....I am following the same method as Rigger did...

Mods - I don't think I am stepping on any toes by posting part numbers and prices because no other supporting vendor (that I know of) is in direct competition with the local hardware store....please edit as necessary...

You will need....

2 hose barbs - 3/8" I.D. x 1/4" NPT(male).....PN 0431643 $2.19 pr

1 o-ring boss x NPT swivel adapter - 4 ORBM x 1/4" NPT(female)...PN 129221 $3.19 each

??? ft of fuel line - 3/8" I.D........PN 2461416 $1.59 ft

2 1/2" hose clamps - PN ??????? $.??

Here are some pics...

If I go this route will this give me the most fuel The ip will take?
I know I will need a better lp but that is a later date.

I am looking on going this route with drilling out the little 4 holes

thanks joe

This is the route that Dave and I took....he seems to still be getting psi at WOT so I assume all is well in the fuel supply situation...

This is the route that Dave and I took....he seems to still be getting psi at WOT so I assume all is well in the fuel supply situation...

Hey Chris ... did you drill out the 4 little holes in the IP inlet, too? I vaguely remember a lot of frantic calculating and varied opinions on whether that would be necessary or not...

No he didn't. I think it was determined that the gain was minimal and the risk of wrecking the inlet was high.

Dave

Correct...I didn't bother....left well enough alone with that IP fitting...

This LINK (http://www.dieselplace.com/forum/showpost.php?p=1895241&postcount=7)is to a post of mine in another thread which has an attached graph comparing a few lift pumps. I thought the information portrayed by the graph would be of use here as well.

The curvey graphs are from data provided by DieselPro earlier in this thread. The straight line graphs are straight off the Delphi web page. Some data between the Delphi dead head and full flow points would be nice , but the straight line graphs at least give you an idea of their operating curve.

I'd like to add Heath's or Kennedy's HO pump to this graph as well.

It looks to me like either parallel OEM pumps or parallel FP905's would be the way to go.

This LINK (http://www.dieselplace.com/forum/showpost.php?p=1895241&postcount=7)is to a post of mine in another thread which has an attached graph comparing a few lift pumps. I thought the information portrayed by the graph would be of use here as well.

The curvey graphs are from data provided by DieselPro earlier in this thread. The straight line graphs are straight off the Delphi web page. Some data between the Delphi dead head and full flow points would be nice , but the straight line graphs at least give you an idea of their operating curve.

I'd like to add Heath's or Kennedy's HO pump to this graph as well.

It looks to me like either parallel OEM pumps or parallel FP905's would be the way to go.

Lets try this again.

I've got a test pump coming Walbro in-line flow thru 45 gph @ 8psi free flow self regulating, unfortunately I'll be out of town when it gets here, once I get some data like p/ns & run data I'll post back here with it.

Any data on the Walbro yet, TD? Is that one of the new FRB-5 models?

No haven't installed it yet, truck mods got overcome by events with Dad's illness & passing, I may get to it next week or week after when I return from Va to Ms

Sorry to hear about your Dad. I've been mostly in the fluids section and didn't hear. Please accept my condolences

Does this flow more than a Racor 230 or 245?

Does this flow more than a Racor 230 or 245?

Not sure what OEM filter flows, more now that inlet & outlet are open, FYI the Racor numbers mean 30 or 45 gph, I have a Racor 460 10 micron on mine as a prefilter to LP & OEM 5 micron filterhttp://www.parker.com/EAD/displayCatalog.asp?menu_parkerid=46&menu_gid=3&menu_divid=109&catid=2556&catdesc=400%20SERIES

Good for 60 gph even though I'll never move that much; more gph capability is less restriction to flow.


Feeding beast was/is to improve flow to the IP,

Now the Good folks at Auto Performance Engineering via a yahoo search for Walbro #2 listing gave me specs on new pump I'll be upgrading to, Ron there was who helped me out ask for him if you decide to go this route.

A FRB-5 flow thru on fail self regulation 11-12 psi & up to 45 gph, has a 70 micron internal "rock screen"

APE had a good price PM me, while not as good as the price from Eric @ Hoesli Diesel (I got a used but good test pump there @ 1/2 cost of new)

Both of these vendors are not currently site vendors so I can't post direct links they are both somebody I'd check out just from their responsiveness to my questions.

Pics of the pump waiting to be installed here

Fittings in the hydraulic section of a farm supplies store will have the right threads....the ones you need are #4 ORBM....I have no idea what that means in regards to AN threads....


# 4 AN fitting, O Ring Boss, Male thread

Problem is hydraulic fittings are high pressure rated, which are thick walled & why the factory pump fitting has such a small ID, lift pump pressure is 6-10 psi max so a thinner wall with larger ID should suffice.

I've been looking at medical supply sites for vacuum fittings that are close to the custom fitting I had made, I may have found the fitting but still need more specs to know for sure if those are going to work.

Ok, I get opening up the filter outlet (to IP) and IP inlet (from filter) so the flow is enhanced. Did I miss if you enlarged the line from LP to filter housing (for those of us using Heath's H/O pump) I read all 18 pgs last nite so i might have missed it somewhere. I also get using a rakor filter before LP. Just a little fuzzy around the edges. Thanks in advance

Scott

I did not enlarge the line from the lift pump, but I did replace the filter manager inlet, outlet, drilled & tapped for 3/8 NPT barb fittings for the inlet & outlet.

Racor installed prelift pump

Tim, do you think that there would be any benefit to using a larger dia. hose or line? It seems to me that unless the line from rakor to LP and from LP to stock filter housing gets opened up (even if only marginally), that its only a half done job. Am I right in my logic? or do I just have too much time on my hands? Either way, thanks for the response.

Scott

No I optimized my fittings to match ID of line coming from the tank, which is about .280", I'll never figger why GM went from tank to lift pump, then necked down the inlet to filter mgr, then even smaller out of the mgr & into the pump with a same small sized fitting, maybe they wanted a nozzle effect to up pressure via necking down/orifice basically. But basic physics nozzle down to up pressure reduces flow, I think part of PMD & IP death are partly due to loss of delivered fuel to the IP, in addition to high underhood heat.

There needs to be a good balance of flow vs pressure to any system, IMO had GM done a full system review of if I do this, end result to whole system is thus; but I suspect IP only engineer said I need X pressure, & fuel system only guy said I can do that, don't want to pay for a more $$$ high press/volume pump so here is one that will meet most needs, a little low on press so I'll neck it down to up the pressure, & flow is good enuff for most guy only needing 195 crank hp.

No consideration somewhere down the line power junkies would want more, or have OPS get flaky, no filtration before the lift pump so it gets weak or dies early, get a partially clogged fuel filter nobody though ahead IMO.

Flow on fail is okay for the lift pump but a heck of a load for the IP to try & make up the difference, lift pressure & voltage at the pump (not control command as it is now) should have been monitored values that if gone; sets a check engine lite, and puts you in limp mode so one does not try to overdrive a IP's ability to deliver fuel with lost lift pressure, this IMO would have allowed better driver & IP life

TD - How's the walbro frb-5 LP performing??

Also,by chance, do you know the size of the stock LP female fittings, so I can replace the weak one(stockLP). Thanks.

I know I'm late to the party, but I've decided to do this mod. I got a pretty good selection of hydraulic fittings and didn't need long to find what I was looking for.

Right now I have a fitting opened to .281 that will work without an adaptor. I have access to a lathe and I hate adaptors...

It has a male JIC -4 thread on the other end that can be used for the connection or I can machine it for a nipple and rubber hose.

I've also machined a special one for you TD if you get ambitious enough and would like to go .3125 Safely.

Machining one for the filter housing is even easier. I know I can get it to .375

Will try and post pictures later... May need help though.

45455

Here is about 10 minutes on the lathe.


Far left is untouched -4
3 next to it have .281 orifice
3rd from left has been machined for rubber hose attachment
3rd from right has been safely opened to .3125
2nd from right is 1/4 NPT for filter housing w/.3125 - room to go to .375
Far right is brass 1/4 NPT - 1/4 barb

Bill, where are you getting your pre-machined fittings from? Looks like they'd move a lot of fuel. Looks good too!

Scott

I've got access to a pretty good amount of Aeroquip fittings...

I've got access to a pretty good amount of Aeroquip fittings...

I haven't gotten into mine yet, but, are you talking about 37 degree fittings and not 45 degree ? I'd be really surprised that the factory stuff was 37*. I'm used to using 37* on airplane stuff.

Thx,
Mike