First, goto a 4l80e.
I have 700r4's and would never consider putting them into that much weight.

Second, you can do the same things with a 6.2 as you can with a 6.5. What you have to decide is if you want to go to an electronic system or mechanical. The electronic IP can normally give more fuel which equals horsepower, but you can make a mechanical system do more than what you need with a little bit of research and work.

 

Make sure the block you start with is healthy. Then go through and do all the reliability mod's such as the PMD and so on.

Swap the exhaust out for a 4" a intake, get a tune, such a Bill Heaths Maxx E Tork tune, HX35-40 turbo, Studs on the top, steel head gaskets, and just for a warm fuzzy some sort of bottom end reinforcement.

Mind you all of this is assuming you have a strong healthy block.

Now if you really want to make a bad a$$ 6.5

-GEP Block and heads
-Steel head gaskets
-ARP studs
-Scat Crank
-6.2 Rods
-Splayed end caps
-18:1 Mahl Pistions
-Monster DB2 mechanical pump with upgraded rotor and plungers (no tune needed!)
-Feed the beast
-upgraded lift pump set to 10 PSI feeding the injection pump
-Bosch High output injectors
-Intake and FULL exhaust, cross over included
-Custom Inter-cooler set-up (bigger the better)
-Coat everything that sees movement with a friction reducing coating
-Bypass filtration system for the oil
-Air fuel separator


That should do it. Of course all the reliability upgrades as well.

 

The again after reading this thread, maybe you should look into his set-up... just sayin'

http://www.dieselplace.com/forum/63...ance-engine-modifications/569849-unique-diesels-compound-turbo-setup-6-5td.html

Thats impressive.

 

The again after reading this thread, maybe you should look into his set-up... just sayin'

http://www.dieselplace.com/forum/63...ance-engine-modifications/569849-unique-diesels-compound-turbo-setup-6-5td.html

Thats impressive.

this set-up is geared more towards racing and dyno, i dont think it would be very streetable in a 10,000-14000lbs motor home, plus the real lack of useable space...

 

4L80 is stronger in stock form? does it need to be from behind a diesel, besides the tc?

i'll likely be using whatever engine or whole truck i can find on craigslist for cheap. i gotta have the serpentine setup, and for reliability and ease i'll probably lean towards mechanical. i may even use a military surplus 6.5. turbo, no question.

would you guys run lower compression and high boost on a rig that heavy/continual load? i really wanna hit that 300hp mark. impossible on a budget?

for sure:
- at least a dirty rebuild; bearings & rings
- clean or rebuilt db2
- '93 lp or aftermarket
- a "feed the beast" mod
- likely some marine injectors
- decent exhaust
- intercooler
- cruise control has to work!!
- zero breakdowns will be tolerated

 

heres our recipe:
verified 6.2l or 6.5l block with a tall fill
shot peened rods
new, or verified heads with hardened seats roller rockers
18:1 pistons ceramic coated
shot peened crank(would stay away from the scat as they have had issues in quality control in the past)
shot peened later model (first 6.2l rods were actually lighter)rebuilt rods with custom ARP rod bolts
5 pin stiffy, with full ARP studded mains
oil squirters
HO oil pump
fire ringed decks
ARP head studs with o-ring mod
HO water pump
best electric fans money can buy
custom built remote mounted turbo kit
hx 40 with 16cm2 gated turbine housing
new .310 mechanical IP turned up 1/4 turn
bosch 974 injectors, popped within 100-125 psi of each other( marine injectors are snake oil)
carter 4070 lift pump or equivalent
high flowing air intake
free flowing exhaust
progressive 4 nozzle WMI injection with 40 gallon tank
a large intercooler with minimum 3" piping
biggest thickest radiator that fits

this will be stone cold reliable and make decent power, but IMO you would probably be better off swapping to a stock 6BT and making more power for less problem/cost, and the option of HD allison automatic always outweighs automotive transmissions... thats a pretty big rig you are powering....

 

300 reliable hp is possible on a cheapish budget, but also takes time to gather pieces (waiting to find deals)and build it, depending on how capable you are... the more stuff farmed out, higher the cost...

 

damned cummins. i hate them for being so great. i got rid of an '03 dodge because the truck and tranny couldn't keep up. for this project, there's just no way to get into one cheap. this is truck country!!

the only thing i'll farm out is machining. i don't mind pouring enough cement in it to cover the end of the sleeves, but not enough to make cooling impossible. the extent of machining would be solely for reliability/longevity.

in a motorhome, RELIABILITY IS KING. second is budget. i don't mind parts scavenging, but i won't be buying fancy turbo set-ups, and i'd like to avoid new pistons. so, any compression changes i'd make would be minimal, unless it can be done with bigger precups or used dish pistons or even thick head gaskets.

so, am i pipe dreaming to keep it over 50 up grades??

 

hey, is there a pros & cons worksheet for the good and bad parts on 6.2s and 6.5s, along with years of production? that'd greatly aid my scavenging profitability.

thanks all, for saving me 100 hours of googling.

 

hmm, the advice dried up. did i propose an impossible scenario; budget horsepower?
you experienced builders should know, ...what's the hp ceiling for a hodge podge of virtually stock parts with no heavy modifications?

at 50mph, my 14k# pig should be right in the powerband, in 1:1. how sad to lose speed up a 6% grade for the sake of 35hp.
with all the usual cheap tricks and no brainers done, my lingering thought is whether to lower compression and shove more boost in so i can keep it spinning around 2400rpms without dropping off.

two questions remain: at what cr/boost do you require head gasket rings, and what do i expect to gain?

 

CONCLUSION:

:deadhorse:alright, i knew going into this that i was posing questions that have already been discussed. however, motorhomes have their own set of considerations, and an extreme need for reliability.

from the responses, ...and lack of, i think it's ridiculous to expect a 6.5 to muster the power needed to move 14k#, plus cargo or a tow car, at a reasonable rate of speed. :badidea:

i've decided to look for an International dt466, 7.6L, with an Allison. their factory hp ranges from around 215-300hp, and 560-860tq. :coolnana: they're easy to turn the pump up, and they're readily available in old school buses. their cr is 15 or 16:1, and should accept a pretty good boost charge.
the dt466 is perhaps THE most reliable diesel on the market and, of course, the Allison will be a far better solution to the torque. :tank:

i like the 6.5 in my k3500 Crew, so i'll leave the 6.5 to do what it does best: light duty.:chicken:

thanks, all

kevin

 

I wouldn't have an issue doing it. 6.5's pull 5th wheels with more than that much weight all the time. If I was going to consider swapping, I'd probably put in a Cummins before I'd think about an International, unless you could find one cheap from an old school bus etc. The only Internationals I ever drove were in body jobs like U-hauls, NA and smoky, so not sure how much better the turbo ones performed. The power potential and parts availability of a 6BT would probably be superior.

Lack of responses don't mean anything about feasibility. Some threads take off and others don't. If posters are anything like me, they meant to respond to this thread and just plumb forgot.

 

asking for lots of power on a small budget out of a 6.5l is probably the reason for lack of response, recipes were given, and the OP wanted to cobble something together with used pieces, probably not the best idea... i still figure a cummins is the best way to go, a 466 is a large heavy engine that will require much more suspension work than a cummins swap, but to each his own...

 

a dt466 is far larger physically, and is strictly medium duty. they are legendary for reliability and I have seen them personally get beat down badly, and continue on, they are a capable engine with a very long lifespan from decades ago until problably us07 emissions maybe us10 emission eras. they usually have a garret or hx40 style t4 turbo.... there are many mechanical dt466's out there and the newer ones,they are huei injected fuel system, powerstroke owners know, this has its pros and cons.....a 12valve 5.9 would work well in your motorhome, the dt466 is likely the same price or cheaper, and slightly more ballsy, but will it fit? I think cost effectively it would go in this order- 6.5-dt466-cummins. all engines listed have different flywheel housing bolt patterns so trans would be a big decision.

 

14K? Pfft, nothing, even in a mostly stock form. I regularly grossed 18-20K with my truck, 5'er, and Jetskis behind that. I had no problems at all on the flats (maintain 60 all day long) and it pulled decent in the grades. It's not a "put it on cruise and forget it" type combo, but I was never a 20MPH roadblock on the hills either though.

Get a non 506 6.5 that is healthy, it'll likely already have a 4L80E behind it, get a standalone controller for the tranny. If you get a mechanical 6.5 you won't need to worry about the electronics, but in your situation if you get an electronic one, I'd swap it to a mechanical. Swap one of the many aftermarket turbos being discussed here on it (since you'll be doing some fab anyways), keep the exhaust open and free flowing, go overkill with cooling, and stuff it in.

I think you'll be happy.

 

yes, i'm a cheap cobbler. that's really the issue with using the 6.5 in this project: whether i'm cheap, or not, cobbling is required and i'd have to fortify the tranny options in order to trust it.

i like the 5.9/Allison, and it would probably do just fine. i'd actually lean more towards the 8.3 or 555 for the extra power.

the IH 466 is also an I6 design and makes great power. apparently it's longevity is phenomenal, too. they're more readily available in buses and other utility vehicles on craigslist or whatever, and they don't come with the price tag of the over-rated Cummins (thanks to the dodge craze).

i'm going to look at both the 8.3/Allison and 466/Allison this coming weekend at a local bus scrapper. each combo is the same cost: $2000. i'll likely try to strike a deal that lets me drive the whole bus home, making it easier to prep for the transplant, plus test the rpms and axle ratio at freeway speeds.

i'm going to google some common parts and maintenance prices and so forth. the 466 takes 30 quarts of oil!!!!!!!!!

 

466 is a good engine, but have you seen one? They are much bigger than a 460,6.5 or 6bt. I would think in a motor home space and front axle weight would a concern. I think you said it was a ford mh, if you could get the front end to hold it up it would likely push like a dump truck in corners. I can see massive fab work. And why?

 

So, um...what's your ultimate goal with this swap vs just leaving what's already in the chassis? More MPG?

If that's the goal, have you actually done any math on how long the payoff will take with your current mpg and (anticipated) new mpg with a diesel? Considering you're going to be sinking at least $2K into the job (realistically 3K and a LOT of hours by the end) I'm not sure the math makes any sense whatsoever unless you plan to drive it a LOT.

 

a reasonable question.
current engine is a ford 460 with no overdrive. mileage is around 6. value of motorhome maxes out at about $7k, and they grenade at around 75k miles (the 454 does too). they just don't last.

i bought the motorhome needing some cosmetic repairs, and needing the interior cleaned up for $900. the diesel swap will likely cost me $3500, and raise the value/sellability of the motorhome $4000, bringing the value well over $10k.
- mileage should roughly double
- hills won't be a problem
- 80mph will be possible and economical
- a tow car won't be a problem

we have been planning a tour of the western U.S., hitting every amusement park, landmark, and giant ball of string for the past 5 years, and i'm going to make it happen (the wife doesn't know i even bought it, yet). :secret:
this 5000 mile trip, alone, will save us about $1500 in fuel by having a diesel.

if i could afford a twenty thousand dollar diesel pusher, it wouldn't hurt my feelings to avoid all of this. but i'm a poor miser, and i'll earn what i need with busted knuckles. :saluteusa:

 

Ultimately... the Wrong combination of engine / components could lead to busted wallet and busted pride as well....

I would seriously consider a GEP Optimizer at the least for a diesel swap.

 

Mileage won't double, *especially* on a motorhome with a huge wind drag surface and a lot of weight. You might get 10/10.5MPG, but based on my experience pulling a reasonably high profile 5er coast to coast with my truck (about 16-17K gross) you'd probably average about 9.5.

3.5 MPG difference over 5000 miles won't even come close to paying for the conversion cost. The increase in the value of the motorhome is debatable but you may have overrated that as well.

5000 miles at 6 mpg (throwing out $3.35/gallon average for gas) will cost you about $2700'ish for fuel for that trip burning gas. The diesel cost at 9mpg, with an average of $3.80/gallon is $2100-ish. The math makes it quite clear - you'd have to drive that motorhome about 25,000 miles for the conversion to even break even.

Even at the 12 mpg you think you might get, the fuel cost is still $1600-ish, so you're barely saving over $1000, so you're at 15,000+ miles to reach break even.

Ultimately I'm not trying to discourage you from the conversion, however I am a realist when it comes to the hard figures and facts if MPG is one of your biggest intentions so far is why you're doing it.

I've driven a motorhome with a 460 - it was one of the first motorhome I ever rented 10+ years ago and is still going strong to this day. It was a fuel pig and certainly wasn't a powerhouse despite such, but it was what it was.

 

Your correct Mark, mileage won't double, but it will go up, probably around the 10 MPG mark. And it will pull hills better and last longer. Driving it will probably be more enjoyable as it will climb hills better and as he states, will tow better. That is a big plus.
Around here, an old 460 gas guzzler motorhome would be a $2k cheap giveaway. Put a diesel in it and its worth 3-4x more. A lot of the costs will be recouped in resale. Same way a diesel pickup holds value over a gasser. Yours and my 1t trucks would be worth $800 in gas, no where near the value they hold being diesel.

 

I just happen to have an International in my sig that I would like to sell. I've posted it for sale before.

Always thought it would be a good start for a toterhome or something.

If I still have it when I ever get able to do a project again, I would like to do something fun with it.

 

Aint worth **** if its not a usable set up, I say keep your GM all GM, So put a older power stroke in it and do a good job at it and it might be worth something.

 

A Powerstroke is GM? I do not understand this post

 

I'm not debating that there are certainly a lot of other pluses to doing a diesel conversion, and like I said I'm not trying to discourage it, but when fuel economy seems to be the overwhelming reasoning behind it I tend to put the raw math ahead of all else.

The resale value is a valid argument, however only if you actually plan to sell it. If reselling it is not in the cards and this is something that one is going to keep long term, then the fuel economy argument comes back front and center in my mind.

Again, don't get me wrong, I bought my pickup (at significant extra cost) in diesel instead of gas for the very same reasons/arguments that many are making here in this thread, however I towed my trailer about 75,000 Kilometers with it so it financially made sense in a long run from the mpg standpoint, and with no intention to resell it at this point the resale argument doesn't yet weigh on me.

 

so it financially made sense in a long run from the mpg standpoint, and with no intention to resell it at this point the resale argument doesn't yet weigh on me.

But, when you bought it, you know you would get the diesel cost back out of it, give or take a but. Someday you will sell it and someday the OP will sell the motor home, its all just part of the bigger picture when you look at initial costs.

Anyways... As was suggested, really inspect what you have for engine bay room in the motor home. That is going to be your deciding factor. If a 460 fits, a power stroke will fit as will a 6.5. A cummins may be too long and heavy. The internationals may be just too big and heavy period. Inspect some school buses and take measurement's, see if its doable on the motorhome.
My buddy's dad did the same thing on a smaller one and stuffed a cummins in, with the 4x4 drive train. It went everywhere, had good power and he sold it for good money, when he stepped up. It didn't have a real frame though, that was a nightmare that they said they would never tackle again. Also on the resale, a lot of people will shy away from buying something heavily modified, they want to be able to look up OEM parts etc.

 

recently near western NY there was a complete 5.9l Cummins drivetrain available with 80,000 miles for $1800. should power the RV without a problem, easily if upgraded. also, being a commercial quality engine, it will run forever. 460 --> 6.5 TD swap requires engine mount modifications, right? im sure the cummins drivetrain will need custom work in this area. after the transmission was gone through (already mentioned in budget) it would certainly 1. cost you less, 2. I don't see a need to go through the engine 3. I would expect better fuel economy vs. 6.5 TD. I could be wrong but some thoughts.

 

I would expect better fuel economy vs. 6.5 TD. I could be wrong but some thoughts.

Really hard to say. It depends on what Cummin's, mine gets better milage towing now that its been opened up but my FIL's 6.5 usually uses less fuel.
My father in law used to always go camping with a guy with a dodge and they had similar 5'vrs. The dodge always out pulled him going up the hill but always took more fuel when they all filled up.
But there so many apples to oranges comparisions to this, its impossible to give one answer. Just like how one 6.5 gets 12 MPG and a similar truck gets 22 MPG, you won't know what a particular setup gets till its all done and tried.

 

I think he'll double his fuel economy, 6 mpg now and if he's not to the floor, he should be able to muster 12mpg average. When mine was still n/a, I got 12mpg towing an enclosed trailer, I bumped into a guy with the same setup as me, but gas, 7 ish mpg.

There isn't much room in a van so bewary of big inline 6 engines, Ford's E van's don't have that much more room than G vans, but at least the Ford's have a proper frame, makes things a bit easier for swaps.