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7.3L international in a deuce?

Josh

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Only time I've seen an NV4500 grenade itself, is when the owner doesn't use the proper fluid. The proper fluid for an NV4500 is expensive and if you try to save some bucks by using cheap fluids your going to shell out alot of cash on a rebuild.

That said. I know lots of offroaders that use them many behind BBC's turning 44s or larger. Other then a broken inputshaft and some grenaded cluchs, Haven't seem much problems


I have a nv4500 waiting to go into my wheeling truck, just waitin' on the cash.
 

YkDave

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Yellowknife, NT. Canada Eh?
NV4500s require a GL4 (castrol syntorque or amsoil MTG) oil to be compatable with their carbon fiber syncros. they will not grenade from the use of a GL5 oil, you will jut destroy the syncros in a hurry.

Im sorry, but the Nv4500, although a good tranny, is far from bulletproof, especially behind something with alot of low end torque.


If you have not seen or figured it out, i am a LD/HD mechanic, ive been around the block more than once and have a pretty good idea about what works and what doesnt.

I dont want to argue about what is good and what is bad and why, because frankly i dont want to hear it, ive seen it or have done it myself!

Now, lets stop de-railing this thread as i would like to get back to my original question about the fuel economy of a 185hp 7.3 IDI in a deuce. I would like to keep speculation aside and hear from someone who has done this swap or something similar.

:beer:
 

Lar45

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I have a 94' F350 CrewCab 4x4 with the 7.3 IDI Turbo, it has an auto tranny, I think the E4OD( don't remember just now) and running 35" BFG MTs. It has 240k miles and I can get 15 mpg on the freeway with it if I keep the rpms below 2000.
I pulled a 35' camp trailer from SLC UT to Pocatello ID and still got 15 mpg, but I kept it at around 60mph the whole way.

When I got it I read piles on the FordDiesel forum. Some of the basic power tuning things were the Injection Timing. Stock calls for 8deg ATC(After )I think the reason was to keep it quieter. The guys on the forum said to advance it to 6-8 deg Before. When I first got it it seemed like it would pull hard up to 2000rpm and then the power dropped off dramatically. After I changed the injection timing it would run great up to 2500 rpm.

The next thing was the turbo boost. I think Ford set the waste gate at 2psi to just clean up the smoke. Adjusting the waste gate is pulling a tiny pin and turning the adjuster rod a few turns and put it back together. I don't remember how many or which direction to bump it up to 6 or 8 psi-ish. Some guys said they were running 12-15psi with good results.

The next big thing is larger exhaust...

With the IDI you can run waste vegie oil without gumming up the injectors like a DI would. When my oldest son worked at Dairy Queen, they would change the oil the fryers every saturday, he'd pump it back into the original 5 gal jugs and give me a call to run down and pick it up. I'd heat and run it through several filters, then run veggie in one tank and diesel in the other. It seemed to get the same milage and power, the engine just ran cooler.

If you already have the engine, put it in. Maybe try to find a turbo and do the other performance tweaks.

One of the guys on the forum said that running a heavy concentrate of fuel additive would clean out the injector pump and injectors. I don't remember the brand he suggested, but it's worked well for me when the engine starts running poorly.

this is a great thread, I was thinking of starting one with similar questions. How do you think the E4OD tranny would hold up in a Deuce?

The 7.3 has about the same displacement as the Multi Fuel, it's just a V8 instead of a straight 6.
I"m sure there are many other things to consider, and I'm not an expert on any of them.

I don't have one yet, but I've got the bug and think I need to build a Bobber. Maybe two and give one to Dad for X-mas.
 
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YkDave

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Yellowknife, NT. Canada Eh?
The issue with the fuel system on the 7.3 IDI is not that it gums up. Its the typical traits of a rotary pump and all injectors. rotary pumps have a failry short lifespan in which they operate efficiently. The head/rotor wear out pretty fast, and with it goes your power an economy, until one day it just drops dead on you. Injectors, like any, through time the springs sag, pop pressure drops and with that goes your power/economy due to the poor atomization and imbalance between cylinders. No amount of snake oil additives is going to fix worn out components, but of course they can be of some help if you have a contamination/buildup issue.


Im going to go check out the 6B after work, give it a good lookin over, if it is in decent shape (rebuildable at least) i will pick it up and use that. If not, i may just go ahead with the 7.3IDI and ZF5/1356 for now and give it a shot. fab up my HX35, crank the pump and see what happens
 

YkDave

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Its already a dog, a dog with one leg LOL

I really couldnt care less about the power, just looking for something that doesnt just pour fuel through it!

Now, one thing i have been wondering, has anyone got a proper HP/tq rating for these. I know the manual shows ~40hp, but that is only by using primative SAE calculation, likely not even close to real world numbers (low 100s maybe?)
 

Gunfreak25

Well-known member
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If you mean the 302, it puts out a max of about 135hp. The best MPG figures I have seen have been around 9 or 10 city miles per gallon. Realistically though, most probably get less than 8.
 

YkDave

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yep, the 302

The guy that gave me the trucks, has quite a few of his own that he regularly drives. He even told me straight up that the best he can ever get out of them is 10mpg on the highway with one of the rear driveshafts pulled!

And i truly believe it...

We went out playing around a little bit the other night and i burnt almost a full tank of gas within ~2hrs and a couple of miles!

of course, poor mileage can be expected from such an old and underpowered beast. but if its going to be that hard on fuel, its pretty much useless to me unless i buy a super-b of gas to follow me around.

Thus comes the idea of this POS 7.3IDI or something better like a 6b, in an effort to get some kind of fuel economy while crawling around the bush. the 302 gets respectable economy for what it is while on the pavement, but it just gets stupid when you take it on the trails!
 

Gunfreak25

Well-known member
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Yuma, AZ
I do see your point. There is obviously room for lots of improvement MPG wise. Why must all things that we men enjoy be so expensive? :lol: I would offroad more in mine but you just end up using A LOT of gas in a vehicle of this class. Lots of revving while barely gaining any distance, the soft sand here really holds you back.

Does yours still have the original 56 gallon tank on it? I suppose off roading LESS OFTEN isn't an option..... :lol:
 

YkDave

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Yellowknife, NT. Canada Eh?
Its got its original 46.75 gal tank

Not nearly enough gas to actually go out anywhere and do anything!

The place we went out to last weekend was only a couple of km out of town, a little bit of dinking around only covering a couple of km in the sand pits and on the trails and neither one of us had much gas left when we got back into town...

At that rate, i should try hanging a bucket over the exhaust to try and catch some of that gas!!!! LOL

I would expect it to not get anything near great fuel economy, but as it sits, it is pretty much useless to actually take out anywhere (to my cabin or go ice fishing up north).



Im going to try and track down an auto trans to throw behind this 7.3 (rather have an auto for crawling around than burning up a clutch or beating up the truck). I know a guy that has another 7.3IDI and an auto behind it, sitting around, im going to go see if he still has it.

I dont expect 20mpg out of it, even on the highway with an engine swap. its a big lumbering beast to try and push through the wind, lots of wind resistance! But i do expect to find a large gain in fuel economy while putting around the bush.
 

tennmogger

Well-known member
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Greenback, TN
If someone had done the exact swap you want to do, seems they would have chimed in by now. Personally, it seems you hate that engine. I can't imagine why anyone would put such a hated engine in any truck they had!! I don't think you will be happy with it.

I have an old 7.3 IDI NA engine in a U-Haul truck, ahead of a C6 (Ford E-350), 4.11 rear end. You mentioned wind load, and the big box is a BIG wind load. This truck seems to get 10 MPG year after year, slow or fast, loaded or not. I don't try to drive fast. 55 is fine for me. It sucks (..spits black smoke) at altitude (like in Rocky Mtns) but runs fine on the flats and at low altitudes. I like the engine. If there's a shortcoming it's in the thin waterjacket that sometimes gets perforated by cavitation of the coolant. Be absolutely certain to run SCA in the coolant.
 

YkDave

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Scored a 6B for free today...

Its a VE pumped engine. nothing spectacular, 150hp @ 2200rpm

Capable of more power than i would like to put through the stock t-case and driveline, so i will keep the modifications simple (3200rpm gov spring and a little more fuel, just something to get around the 200hp range)

a smidge more power would be nice (yet, i know im going to kill the driveline, the ol gas pot has twisted off many shafts!) and im hoping for a nice bump in fuel economy

I just need to go find an old smashed up dodge/cummins to rip the adapter plate/flexplate and transmission out of!
 

Gunfreak25

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Yuma, AZ
You know, it would be interesting to find out just how much power the driveline on the G749 series can handle before things start coming apart. The most powerful conversion I have seen was a 502 Chevy BB. In fact, I was talking with the guy who put the 502 in his M135 and I have seen many other conversions as well. 350's, 427's, 455's, etc. I have yet to hear of any break down issues with the rest of the driveline. Seems the Tcase on these is pretty darn beefy.
 

YkDave

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Location
Yellowknife, NT. Canada Eh?
Yes the Tcase seems pretty beefy, the driveshafts are marginal, but the axles are the weak point.

I have a whole pile of twisted off axleshafts in the back of my parts truck, they were all twisted off by the good ol GMC 302!!
 

YkDave

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Location
Yellowknife, NT. Canada Eh?
Having trouble locating any kind of information on the axles and the torque output of the 302???!?!?!

Curious to know what the torque rating is on them...

trying to get a ballpark range of torque i can throw through the axles before things start to snap. I already have quite a bit of evidence that the 302 can twist these axles off, but gearing also does great wonders at breaking things.

I plan to use a dodge 727/47RH tranny, so it obviously isnt going to have the stupid low gearing of the 303M transmission. but this engine also has gobs of torque (470lbft @ 1300rpm), so in first gear we are looking at roughly 1150lbft @ 1300rpm (somewhere around 2000lbft if you factor in the torque multiplication for the torque converter)

Just a rough guess of the 302 pushing 130lbft, with the ~15:1 low range of the 303m, we are looking at roughly the same torque going to the driveline.

So, with any luck, if my guesstimate on the 302's torque is close, i dont think it will be too had on the driveline. But it definitely makes me think twice about squeezing a little more power out of this 6B!
 
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