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Discussion Starter #1 (Edited)
Hi all,

I finally got the goodie i have been dreaming about: Eaton M112 supercharger from a V8 Jaguar. It will boost my '87 C10 6.2.




Superchargers are not common in 4 stroke diesels, i know, but for me that is just a reason to supercharge. Why? Why not?

Other than doing something uncommon, i prefer SC because
i neved had one before,
i don't like turbo whistle and i do like v8 true duals sound,
i don't like on-off triggered turbo boost but i do like flat torque curve like in a big block,
project with SC is more interesting than playing with turbo exhaust pipes,
contemporary SC with a boost by-pass the parasitic energy loss is manageable,
superchargers have bigger wow-factor

The plan is to mount the SC on a side of the engine and route a pressure tube from there. For by-pass i am looking for a small (~2"/50mm) throttlebody (tips where to find?) and will program a micro-controller to run a model airplane servo that actuates the valve. Micro-controller inputs are TPS and TCC. So that on idle and TCC engaged the by-pass is mostly open (0.5 - 1psi) , and per TPS the boost gradually increases up to ~10psi. The boost curve adjustment will be try&error.

I think i will mig-weld the SC crank pulley to front of the accessory pulley. However, it is surpringly hard to find a steel (weldable) pulley with 8 grooves and diameter 8 - 9". The pulley on SC is 8-groove 2.8". Eaton M112 can take 12krpm and flash 14krpm. So at 3800 rpm engine redline and 9" crank pulley would equal 12200 rpms at SC. i think a 6-groove pulley and belt would work too, although SC end has 8 grooves pulley. What do you think?

Do you know any OEM pulleys to look for? The pulley diameters are not listed on replacement parts. The pulleys that Supercharger companies offer are ridiculous priced, like $300 for a metal ring. And they are usually aluminium which makes mig-weld impossible, and there are hardly any big enough diameter pulleys, due to the fact that gassers rev higher. Any tips to find the pulley are appreciated.

I might update the thread with news and pics when progress, if you're interested.

Any comments and ideas are welcome for the project.
Thanks :)

.
 

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Hi all,

I think i will mig-weld the SC crank pulley to front of the accessory pulley. However, it is surpringly hard to find a steel (weldable) pulley with 8 grooves and diameter 8 - 9". The pulley on SC is 8-groove 2.8". Eaton M112 can take 12krpm and flash 14krpm. So at 3800 rpm engine redline and 9" crank pulley would equal 12200 rpms at SC. i think a 6-groove pulley would work too, although SC has 8 grooves. What do you think?
I think you will have to have a pulley custom machined for you. I have never seen a production 6 or 8 groove pulley that large and V pulleys that size are cast.

Dorman makes a 6 groove 6.5" pn# 300-124 which is a metal PS pulley, but you wont be able to push 10 psi without the 6 groove belt slipping and you will probably have trouble with the 8 groove slipping up top.

I would forgo the serpentine setup and implement a cog style off the crank instead. That way you only have to design it once.
 

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Look up Belt source in Beaumont tx. Woody can get just about anything belt related. Including cast steel pulleys that are weld able.
 

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Might try electro-magnetic clutch activation. Similar to AC clutch. Similar to the one found on Volvo marine diesel.
 

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Have you done any CFM comparisons on this S/C vs what the 6.5 requires?

There was a HMMWV/Marine S/C setup back in the day. Would really help if you could locate that pulley or borrow one to copy.
 

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Cool project. I have no help for ya, but I'll be interested to see how you work it out. :thumb:

If all else fails, you could buy one of these!
 

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Discussion Starter #8 (Edited)
Hi,

thanks for comments.

I found a $55 Holley 6-groove 6.7" power steering steel pulley at Summit.

Then i played with math formulas to calculate supercharger pressure.
Google found a few sample equations and online calculators.
The outcome of the calculations is that i realized while i don't know the Volumetric
efficiency of the engine and charger setup,
the boost estimation is a shot in the dark. depending on the flow efficiency
the equations result a few psi up to 10+ psi of boost.


quote:
"the 0.9 factor is the ~VE for the typical intake tract under non-boosted conditions.
The number 3,456 is just a mathematical factor to make the units come out properly.

CID*rpm/3,456*(.9) = engine airflow requirement
((blower CFM/airflow required)*14.7) – 14.7 = boost

So, as an example if you have a 350 and a 1,000cfm blower and want to make peak boost at 6,000rpm:
350*6,000/3,456 = 607*.9 = 546
1,000/546 = 1.83*14.7 = 26.9 – 14.7 = 12.2psi is the approximate max boost at 6,000rpm with 1,000cfm."


in my case
379ci * 3600rpm / 3456 * .85 [eng VE] = 336cfm

Eaton M112 is 112 in3 = 0.065 ft3, so
.065 ft3 * 2.4 [pulley ratio] * 3600rpm * .9 [SC VE] = 505cfm
hence
505cfm / 336cfm * 14.7 - 14.7 = 7.4psi

consider SC VE 80% and calculated boost drops to 4.9psi, on the other hand
if SC VE 100% and Engine VE 80% and the boost jumps up to 11.4psi

If you have comments to the calculation and VE estimation, please share :duh:

~7psi estimation with 2.4 pulley ratio (w/ 6.7" crank pulley) is fair enough for the beginning.
I'll order the 6.7" Holley pulley and start from there.
When i see what this pulley setup gives boost, i can estimate further the
right cu$$$tom manufactured 8-groove pulley size.

The mad-max style magnetic clutch SC pulley would be cool :) However,
that's too much trouble for me. The pressure bypass does almost the same but smoother.

When i receive the lower pulley and have it placed i can begin to mount the SC and line up the pulleys :coolnana:

Thanks.
 

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Discussion Starter #9 (Edited)
been busy making my living, so no much progress with this, however a little update

ditched the original fan and shroud replaced by electric fans 14 and 16" to make room for the charger belt. the fan temp sender is on rad lower hose, to where i fabricted an adapter. two circuit sensor Facet 7.5604 / 82-77C (180-170F) and 87-82C (189-180F), works just perfect with 88C (190F) thermostat, temp gauge stays steady. one fan hits in when idling a while, the other fan has been on only once when i was moving a heavy trailer back and forth on a yard.

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as i don't have a lathe, the Holley pulley and original V-belt pulley are on a machine shop, they will lathe and turn an aluminium adapter to bind the pulleys together. the adapter needs to be 1" thick in order to have SC belt clearance away from water pump. i should have the pulley setup back this week.



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the plan is to mount the charger driver side of the intake, on top of the engine, and route the pressure tube from there. it is a bit tight fit, but should be doable. the second option is passenger side below alternator.


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One question came up too... how should the engine breathing be designed? now it breaths to the intake which has the (minimal diesel) vacuum. when the intake is pressurized the breather system might not work as mr General Motor designed it, and ie might push oil out on the crank lip seals.
Ideas, or is it a problem overall? How it is engineered on turbo 6.5 or 6.2 banks?

thanks :beerchug:
 

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So you are keeping the charger under hood? I have planned as SC too, thought about making a custom intake with water-to-air cooler.

I think turbos put the breather in the intake before turbo. Which means you get oil soot all over the insides of turbo. Some have made catch cans which helps catching most of the oil from it.
 

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Discussion Starter #11 (Edited)
Yes, the charger will be concealed under hood. I prefer stock appearance. Contemporary super chargers, like Eaton, are relatively small size.

I got the pulley setup back from the machine shop today. My first impression they did a good job. The adapter is turned from a solid aluminium block. My plan-A was to weld the charger steel pulley but the original accessory pulley is cast iron with a rubber center ring.

About the engine breathing; thanks for reply... i think i'll just go the easy road and
route the crank case ventilation to charger inlet. The rotors will be messy for sure,
but this ain't a pro street high tech show project or truck. If that turns out
to be a problem i'll fix it in edition 2.

Now that i have the pulley, i can continue to mount and line up the charger :thumb:





 

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What it doesn't take a day for a machine shop to do something like on the TV shows?
Hahahaha
 

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What it doesn't take a day for a machine shop to do something like on the TV shows?
Hahahaha
A whole day? they make it seem like a 10 minute job. :confuzeld
 

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Eurot mainittu, torilla tavataan! :D Where in Finland do you live?

Being a machinist I'd say that is a 30min job if you dont need to waste time looking for material and tools.

E: and assuming you have a drawing ready.
 

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Discussion Starter #17 (Edited)
some progress since last update

charger cradle


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charger in cradle. pressure flange waiting for pressure tube alignment and cut


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inlet flange and tube. the tube will have nipples for by-pass and breathing


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pressure box unfinished. the intake manifold ring is a cut of a fireplace chimney conduit


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by-pass valve and servo. the by-pass is an universal heater core valve, i'm afraid it will be too small, we'll see how much pressure the setup generates


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mounting starting point


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mounted. the front bracket was easy to weld in place, back support took hours, since for the lower bracket there was no place to be bolted to but the exhaust manifold. upper is held to intake bolt. looks simple but overall (at least for me) it was hours of brainwork and cut and weld to make it fit, sturdy, aligned and aesthetic enough, with service access to injectors and glow plugs


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the mounted cradle only


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there it is


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on initial fit in experiment i was afraid the water hose was interfering, but it clears just about fine under the charger nose


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the pressure tube will be pretty short

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alignment. i got to borrow a pulley laser alignment tool from a friend. first time i used such a gadget. without it the alignment would have been just a best guess.


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charger fits nice under the hood


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the uncomfortable dirty work is done :clap:

i browsed for belt tensioners. in picture an early 2000 Escalade tensioner seems perfect for my project: the tensioner backplate is flat so the bracket would be easy to fabricate

also waiting:
the pressure box, -tube and charger flange alignment and weld.
inlet pipe connect, air filter setup, engine breathing and pressure by-pass
finding a correct length belt
and a finishing touch...

the missing steps won't take long, since right now i am very excited to see the charger rolling :coolnana:

@Catrik, i am from Helsinki vicinity
 

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It is looking sweet :bigglasse

A lot of the LSx style tensioners on 5.3s and 6.0s bolt to a flat surface on the water pump and should be usable, compact units for you with a fabricated flat mounting point.
 

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That's brilliant.
You should really think about getting a J-code intake manifold.
The can be bought for well under $100 but shipping cost to Finland might suck.


On supercharged diesel engine they don't typically run a bypass. On gasoline vehicles the by pass is operated by engine intake manifold vacuum so that the supercharger isn't trying to force air through a mostly closed throttle plate.
 
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Discussion Starter #20 (Edited)
Thanks for your support and feedback.

Good to hear a hands on view with the LS engine tensioner. A local dealer should have LS (Escalade) tensioner stocked, i'll go grab it before weekend.

Measured the belt length 54.5", found out at Summit that Dayco lists belts that size. However, as short multi-rib might be rare to find at a corner stone parts store here. The fastest way might be to place an order across Atlantic.

Thanks for the diesel by-pass tip. My idea with the by-pass is to enhance efficiency and mileage. At idle it does not make sense to generate excessive parasitic boost. Same with highway cruising. Yet, as the air supply potential is there all the time: when needed the boost will jump up instantly when by-pass closed. However, as i don't have any personal exprience with superchargers before (even less with supercharged diesels :D), i have no clue how much this mechanical air pump combo will put out pressure at idle and low engine speeds. The by-pass might turn out to be useless, as you say. We'll see soon.

The J-code intake is a good idea and added to the wish-list. I would need a new injection pump some day too. I'll find and do the manifold the same. Of course it is possible that i need to join the post a pic of your carnage thread when charged, hence have to recompose my active wish-list :duh:

Talking about IP's -- how much the stock IP can be turned, to compensate boost, before hitting problems with pump behavior, drivability etc? I already adjusted injection 3/8 turns a good while ago. I am planning to turn further once test drove it charged. Would 3/4 - 1 turns from the basic setting be too much for the pump, where is the limit usually (and what problems you face when the injection setting is too generous for the pump)?

Thanks
 
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