7.3L international in a deuce?

[TexAndy]

The IDI engine has decent potential, however, The problem with them is the compression is so high on them compared to the powerstroke that if you Turbo it, you can only get 5-10PSI of boost reliably, which would be enough. If it were I, I would sell your current 7.3, then buy a an actual powerstroke. You would be able to get between 14 and 18 MPG with it if you can keep your RPMS below 2000. The powerstroke is most fuel efficient at 1600 rpm. If you go the Powerstroke route there is also a major aftermarket for the engine, power adders and such. You could push that 275hp up to 400 hp easily and the engine will live.


That being said, in my opinion, if you want power and mileage, go the powerstroke route. If you want to just use what you've got, I don't think you will be un-happy with it, but it will not be fast, although it could be made to go faster with the addition of a small wastegated turbo set to open about 7psi.

What's the max rated HP engine you can run in a deuce before you start running the risk of producing too much torque in any particular gear for:

Transmission, transfer case, axle gears, driveshaft, etc...

 

[dragonwagon]

7.3 orginally designed to run 250,000 most will do well over 300,000 with good maintence . Power Ok not great .

To bad you dont have a inline IHC DT 466 thats a heck of a good motor . My Hercules takes a death run ill let you know how the 466 works in a deuce

 

[m16ty]

I wouldn't trade a whole truck load of 7.3 IDI IHs for one 6bt. The 7.3 IDI is a little better than the GM 6.2 but not alot. The 7.3 is a ok engine for a pickup truck but I honestly don't think it would out perform a turned up multifuel.

On all of the early model IH diesels, you've really got to keep them wound up to get any power. If you ever let the RPMs get below 2,000 it will fall flat on it's face. You also have to really rev them up to get a heavy load started without stalling. No low end torque.

 

[Brian H.]

What's the max rated HP engine you can run in a deuce before you start running the risk of producing too much torque in any particular gear for:

Transmission, transfer case, axle gears, driveshaft, etc...

TexAndy,

I know very little about the Deuce and I'm not going to pretend I have an idea of what it's limitations and specs and what the components will take.

My knowledge is limited to the 7.3L powerstroke and related engines and most of that knowledge is from doing performance work on them, installing exhausts, chips and programmers, turbos and that sort of thing. I have never been inside of the engines beyond changing injectors, and head bolts to head studs. I was also assuming that if he were to do what I suggested, that he would be using the ZF5 trans. he has know. From what I have read here the Deuce transmission is rated for 400ft# of torques and is the weak link in the drive train.

I'm not one of those "internet people" I will speak on something I know about, if I don't know, you won't hear me spout some BS to get a post count up. I've been doing a whole lot more reading and learning than I have been posting.

Thanks

 

[YkDave]

I dont plan to use this as a pavement princess, its going to be used for what it was built for, drive the heck out of it in the bush!

For that reason alone, Any modifications (to the engine or otherwise) are going to keep it as reliable as possible. That means a carbed gasser (say goodbye to fuel economy) or a mechanical pumped diesel (no flowerpokes, dmaxes or ISB cummins's)

Ive got a whole slew of 350s, got a 400hp torque monster sitting in my camaro that i havent driven in years. but then that brings me full circle to the fuel economy thing, i havent driven the camaro for years because it cost $100 in gas every time it left the driveway LOL

I would love to just drop my ford 5.0L in there, it gets alright fuel economy, but i just dont trust electronics for the application. If i go out and drown the thing in the summer, yes it might work fine for a while after that, but what happens when im 300km out of town up the iceroad when its -50c or lower and the engine calves out?

Yes i usually have my iridium with me, but a call for help is not much good when you have to sit in the middle of the tundra for a couple of hours waiting for a chopper or twatter to come saver your azz (granted weather is even permissable at the time!). i just dont have that much faith in EFI!

 

[YkDave]

I wouldn't trade a whole truck load of 7.3 IDI IHs for one 6bt. The 7.3 IDI is a little better than the GM 6.2 but not alot. The 7.3 is a ok engine for a pickup truck but I honestly don't think it would out perform a turned up multifuel.

On all of the early model IH diesels, you've really got to keep them wound up to get any power. If you ever let the RPMs get below 2,000 it will fall flat on it's face. You also have to really rev them up to get a heavy load started without stalling. No low end torque.

If you know anyone willing to trade a boatload of 7.3s for a decent shape 6bt, let me know, i would entertain that idea LOL

The 7.3s are turds as far as power is concerned.

We are looking at roughly 250hp SAFELY with a turbo. Again, safely is the key, i dont want some pile of chit thats going to leave me stranded in the middle of the tundra!

Thats alot of work, alot of weight and alot of hassle for a measly ~250hp. especially if their is not going to be any sort of gain in fuel economy...


On the other hand, a p-pumped (887/911/912/913 pump) 6bt is a guaranteed 300hp without dropping a dime on it and a guaranteed jump in fuel economy. I just need to come across one for a decent price (people figure the **** things are cast of gold) and i would jump on it like a fat kid on a smartie!

 

[Gunfreak25]

Based on your replies I'd say it sounds to me like you already have your mind made up, Dave. Honestly, if MPG is that much of a concern don't you think a slightly smaller Military Vehicle or other big truck would be better suited to meet your needs/wants? You may be trying to make a silk purse out of a sow's ear. Not trying to discourage your idea at all, I am a project nut myself and often have a list of half finished things. But one also has to be realistic and keep a mental note about the limitations of a a vehicle that was designed before most of us were born. No matter what you decide to put under the hood, it's still going to suck your local gas station dry. It weighs 7 tons, has a 6.17:1 gear ratio and the aerodynamics of a barn door. I suppose if you REALLY wanted to, one could hit the 15 or 16MPH mark, but at what cost? I would stick with that 302. If you want better mileage, throw some super single Michelin 46" tires on and pick up an REB shift kit for your Hydramatic (I see one for $275 on another board). If your Military thought the G749 was that underpowered then they wouldn't have stuck with it for so many years. This is of course, my Although most people I know would argue it's worth a lot less than that.

With the above having been said, have you considered a GM 400+ big block? A 427 would do the job nicely, and with some simple mods could still give you 12MPG easy. More, if you went with larger tires and a tranny with an overdrive.

 

[YkDave]

I do have my mind set, i know what the engine is, its a turd pile. Thats just what it is, as will ever be

I just wanted some FIRST HAND information from someone else that may have done the swap, maybe its worth an extra couple mpg, maybe not.

I dont expect 30mpg out of it, but it can sure as **** do alot better. My 6bt can still do 18mpg pulling 15k/lbs on the goose (gcvw around 30,000lbs, 8k truck, 7k trailer)

gearing is null, yes its 6.17:1, but its not running 31" street tires either. actually its about the equivalent of running about 4:11 gears on a regular pickup, not the greatest for economy, but not a very low gear for the given tire size.

Essentially, its like a loaded 1ton pickup, with 4.11 gears and a few sheets of plywood bolted to the front of it. no reason it couldnt get WICKED fuel economy while putting around the bush and no reason why a person couldnt get ~15mpg on the highway.

 

[YkDave]

I do have my mind set, i know what the engine is, its a turd pile. Thats just what it is, as will ever be

I just wanted some FIRST HAND information from someone else that may have done the swap, maybe its worth an extra couple mpg, maybe not.

I dont expect 30mpg out of it, but it can sure as **** do alot better. My 6bt can still do 18mpg pulling 15k/lbs on the goose (gcvw around 30,000lbs, 8k truck, 7k trailer)

gearing is null, yes its 6.17:1, but its not running 31" street tires either. actually its about the equivalent of running about 4:11 gears on a regular pickup, not the greatest for economy, but not a very low gear for the given tire size.

Essentially, its like a loaded 1ton pickup, with 4.11 gears and a few sheets of plywood bolted to the front of it. no reason it couldnt get WICKED fuel economy while putting around the bush and no reason why a person couldnt get ~15mpg on the highway.

I dont expect to see great economy on the highway, because of course the aerodynamics are lacking, i would just like something that will get more than 2mpg whether its doing 5mph or 50mph LOL

Actually, high speed is of little to no concern to me, again, it is going to be punching through the trails going to my cabin, going ice fishing, ect.

 

[Josh]

Just so we are clear here, you are talking about an m135/m211 right?

 

[Gunfreak25]

Yes, the truck in question is a M211. It was given to him for free too. Lucky dog.


Dave, whatever you end up doing I am sure it will a good conversion. DO take lots of pictures, many are watching.

 

[YkDave]

Its a 1954 M135

 

[Gunfreak25]

And two M135's at that!

I found this after some searching. Might want to try contacting MajorTom for more info.

View topic - Manual Trans early deuce...? :: Steel Soldiers :: Military Vehicles Supersite

 

[mudguppy]

What's the max rated HP engine you can run in a deuce before you start running the risk of producing too much torque in any particular gear for:

Transmission, transfer case, axle gears, driveshaft, etc...

... From what I have read here the Deuce transmission is rated for 400ft# of torques and is the weak link in the drive train. ...

not sure where you read "400ft-lbs" at? everything i've seen on here is ~330ft-lbs, and that's been pure speculation. regardless, i concur with you that it is the weak link due to several different design issues and has shown only marginal reliability behind stock-fueled MF's (135-ish hp / 305-ish ft-lbs). it isn't a strong transmission and i doubt Spicer is particularly proud of it in it's manufacturing history.

to be honest, i think it would be marginal behind a moderate small block and questionable behind a mild big block, let alone a diesel rated above 200hp / 400+ ft-lbs. and i sure as chit wouldn't trust it behind any 6bt Cummins.

I wouldn't trade a whole truck load of 7.3 IDI IHs for one 6bt. The 7.3 IDI is a little better than the GM 6.2 but not alot. The 7.3 is a ok engine for a pickup truck but I honestly don't think it would out perform a turned up multifuel. ...

 

[YkDave]

Dont worry, the 303m would be going in the box of my parts truck along with the 302 if i were to ever swap engines!

Not only because it would be pretty much useless to any other engine swap (its not like it actually bolts up to anything), but because of the fact that its pretty **** primative LOL

 

[YkDave]

Got a line on a 6b today, not exactly what im ater, its a VE pumed engine, but it looks like the price is going to be right!

Just need to figue out a trans to go behnd it...

 

[mudguppy]

the shortest [advisable] trans you can get will be an NV4500 5 spd with the GM 6" fixed yoke tailhousing. you can start with a GM or Dodge nv4500, but you'll need to swap out the input shaft to a Dodge input if you use a GM trans.

if the 6bt is not aftercooled, this will simplify things greatly and you can use the stock deuce radiator and basically be done. if you up the power and/or add an intercooler, you'll run out of length under the hood.

 

[YkDave]

I would like to go with a slushbox, not sure what yet. 47RH would obviously be easiest as i can swap all of the dodge parts onto it (flexplate/housing), but i would like to go with something a little more heavier.

Worst comes to worst, maybe just go with the 47RH and a 205 tcase (so i still have a low range)

The 6B im looking at is a non intercooled industrial engine. Havent had a chance to look at it closely, but im going to assume its got a constant speed gov, which isnt going to be great, but it'll serve the purpose if it is.

If i go with a manual, i would be skipping the rinky-dink crackerjack trannys (nv4500/5600 especially) and step up to a small eaton/fuller (i can score them for a decent price). its amazing how easily a guy can blow up a single countershaft transmission...

 

[mudguppy]

hmm, i seem to be missing a reply...



anyway, i replied to challenge two things:

1. the 47rh, while 'marginal' in stock form, is the transmission that is built up the most often behind high hp competition diesels (including some hi-HP D-maxes). it can be built to hold any power rating that a small diesel can put out. any.
2. do you know anyone that has 'blown up' an nv4500/5600? i don't. haven't even heard of any. there are many broken input shafts - those seem to be found in drag trucks doing boosted 4wd lauches and 550+ HP. and there's also plenty of them withstanding high-HP sled-pulling abuse. i don't think a deuce can stress a tranny as much as a 1300hp / 2000 ft-lb 4wd sled pulling truck can. not exactly what i'd call 'rinky-dink crackerjack' trannies...

although, early nv5600's did have some fatal design issues, so the '5600 isn't a great example. but the '4500 is nearly indestructible, and with an upgraded input shaft and the right clutch, it essentially is.

 

[YkDave]

1) i am not going to spend the required $3k+ to make a 47rh 'reliable' behind a cummins

2) i have blown up a few myself, behind stock and modified engines and have seen MANY others spill their guts. The biggest downfall of the 4500 is the fact that you can pour $4k+ into it and still blow it up almost just as easily. It suffers from a weak case and the obvious dowfall of a single countershaft. Under load, the countershaft deflects as does the case, catch it just right and your walking home.

An nv4500 is marginally strong enough to handle its rated 440ft/lb torque. Anything above that is a gamble, no matter how much money you throw at it. And like anything else, its traction that breaks parts. Big difference between a sled puller that can spin all 4 tires on a semi-loose ground, and a big tank trying to roll over 6 bigazz tires.

In the end, it boils down to being a not too reliable choice. A little different stroy around where you live maybe, but up here pretty much everywhere you go its either muskeg or bedrock, this is the edge of the tundra. rock = weak parts go boom!