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7.3L international in a deuce?

simp5782

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I will revive this. I am looking at the 7.3 into my 5 ton. Yeah people say the 6.9 and 7.3 IDIs are turds. Yeah you wont win any pulling contest or yank a tree down, I will however tell you that the IDI will get you there everything pulling whatever you want at its own pace. My truck has over 600k on a NON rebuilt engine and I have grossed 40-45k with my 6.9 NA and she will do it day in and day out with 4.56 gears getting 12mpg loaded and empty . Parts are alot cheaper and easier to come by than the powerstroke. Granted the DI is nice, but you will melt that powerstroke with the non intercooled 94.5 - 97 model engine. the powerstroke is computerized so you have to factor in computers and what not and the other things that can go wrong.

The DB2 pump is by far impressive for what you pay for it. The 6.2 shares the same pump. Swap the 6.2 gov spring into your ford DB2 and your in buisness for 3600rpms. The uhaul version of the 6.9 and 7.3 is the best due to it has the air compressor system built in for the air ride if it has it. Uhaul engines are governed to 2800rpms though. IDI performance parts are limited but I have seem them put down numbers of 600hp and 800ft lbs for $2000 in motor work.

Things to do:
Moose Pump - check with agnem on Oilburners. It by FAR opens the DB2 pump up. WIll run you $400 - $600 depending on how worn out your pump is and what needs to be replaced.
Head Studs $245 from Summit ONLY AVAILABLE for 6.9. The 7.3 studs are $900.
Fire ring head gasket $60 each from DPS
BB code injectors for $30 each or Moose misters also check with agnem he has the video. They are costly @ $900 a set but well worth it.
Add a turbo, wastegated ATS with an aurora 3000 will run you 500$. Shorten your wastegate rod and get a pyrometer.
Intercooler it. you got tons of room under the hood get some pipes and make your own kit ( i did on my F250 turbo IDI for less than $300.
Camshaft - 12% increase in torque and torque at 200 less rpms.Check with typ4 on oilburners. He makes a MEAN torque camshaft for the IDI he grinds as they are ordered $400.
4" + exhaust straight piped $250
Clean the heads up, they tend to have alot of slag in the valve ports.
The 85-87 6.9 engine is better than the 7.3 due to the thicker cylinder walls.

PLEASE do not put the ZF5 behind the IDI, you will regret it with the dual mass flywheel. You spend the $600 for the solid flywheel conversion and you will like it better. 6.9s are SAE 2 bellhousings so you can hook it to ALOT of things. Find a S1600 schoolbus with a 5spd 4054 spicer and ull be set. I have seen the engine and tranny combos from $300-$500.
I attached a link to the dyno graphs for the differences in mods I talked about earlier. Also the bottom link is for the moose mister video, THEY ARE VERY IMPRESSIVE. You can hear the high pop pressure. If it says the video doesn't exist just click on the play button on the black screen.

Dyno graphs: Moose pump & Moose injectors. - Oilburners.net

[media]http://s218.photobucket.com/albums/cc123/SD70M/2004-10-26/Videos%201/?action=view&current=moosemister.mp4[/media]
 
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Gunfreak25

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I hope Dave does this. Had I not opted for the 6.2 I would have definitely looked at a 6.9 or 7.3. Bulletproof engines and easy to acquire. FWIW, Tom at Alfa Heaven did the 700r4/6.2 swap in a few M211's. He said he hauled 2000 gallons of water at 75mph routinely, he loved the setup. That is close to 30,000lbs. Another good example is the 1940's Class 530 B firetruck based on the CCKW chassis.

The trucks weighed 20,000 dry and grossed at 24,000. All powered by 6.66 axles, a GMC 270 Inline 6 and the Clark 5 speed with a 2.63 low range. That's 90hp by the way, with the 270.
 

simp5782

Feo, Fuerte y Formal
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I hope Dave does this. Had I not opted for the 6.2 I would have definitely looked at a 6.9 or 7.3. Bulletproof engines and easy to acquire. FWIW, Tom at Alfa Heaven did the 700r4/6.2 swap in a few M211's. He said he hauled 2000 gallons of water at 75mph routinely, he loved the setup. That is close to 30,000lbs. Another good example is the 1940's Class 530 B firetruck based on the CCKW chassis.

The trucks weighed 20,000 dry and grossed at 24,000. All powered by 6.66 axles, a GMC 270 Inline 6 and the Clark 5 speed with a 2.63 low range. That's 90hp by the way, with the 270.
One of the new members on here from around my area picked up a M211 with a 400sb in it and a SM465? i think its what he said. I told him to ditch it and get with the 6.2. The 6.2 and the idi are basically cousins. I was looking at some 6.2s on GL for good prices.
 

T-Wrecks

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I have an F550 pick-up conversion with a powerstroke. I would not put a 7.3 of any configuration in a truck, I would opt for a cummins myself. Right now I need to put injectors in my truck. Sad thing..... in a 7.3... injectors dont last and almost seem to be a maintenance item like brake pads and rotors. You dont want to waste money on rebuilds, all they are, are cleaned up junk and they seldom replace anything. One would spend money on new, so for a couple of grand to replace injectors, you would be way better off replacing the engine with a more durable, easier to modify cummins 12v or 24v. Just my thoughts though. If anybody is looking for a great running 7.3 powerstroke, turbo and all..... let me know, it needs injectors!
 

simp5782

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The 6.9/7.3 IDI parts are pretty cheap. $32 each for new Delphi BB codes. The issue with a cummins is that everyone in their brother wants one and they are pricey. I can build an IDI with all kinda mods for the price it would cost me to buy a used running 12 or 24v. the issue with them is that everyone selling them they are mostly worn out. The cummins are great engines don't get me wrong it is just that if your on a limited budget you might spend 5-6 buying a used motor and having to go through it to get it refreshed.
 

hardhead

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You should think it over some more about 20 years ago I repowered a 135 with a 391 gas (about the same size) had to hack a hole in the floor the radiator didn't have enough cooling capacity and the service brake linkage hit the exaust manifold before the brakes fully engaged then the transfer case is not a two speed and the 24V issue so be ready for a strruggle but I am sure you can handle it good luck!
As much as i have sworn i will never do anything with this POS engine, it has got me thinking...

Ive got an old F350 im cutting up for a bush buggy, the 7.3L IDI international and ZF5 are coming out of it to be replaced by a BBF and auto.

The engine is a turd (like all IDI diesels) but on the bright side it does have a little bit of power over the ol 302 thats in this heap of scrap metal.

Just wondering is anyone has done this swap yet and the results...?

Im more or less just curious about the mileage. I could care less about it being a slow beast (what do you expect), but i would rather not have it burn fuel like im doing mach5 across the sky. Granted the IDI diesels werent too great for mileage to begin with, hopefully their might be something to gain.
 

Section8

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Little Fort, B.C., Canada
Mpg

Just a quick thought here.
I own a 1955 M135 and am also pondering a repower since my old 302 is missing lots of parts and is seized.
I am currently looking to swap the ring and pinion to a numerically smaller ratio.
The part numbers for the sets are H110. Think they were made by EATON.
At any rate there is three ratios available for the axles.
There is the typical 6.17 that are run in these trucks a mind blowingly slow 7.20 and a smaller ratio of 5.43!!!
I am trying ever so hard to find these gear sets for these axles and have a line on some but do to my business being in the off season money is a shortage.
They are pricey at around 600 bucks used and 1000 bucks new. Canadian dollars for me.
Just another idea for that hard sought MPG issue.
I am also looking at a 4BT engine. Think the 6BT might be a hard fit in the engine bay.
Just my thoughts.
Good luck and keep us posted!
 

Gunfreak25

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Here's the poop on the 6bt. It will fit, but you will need to cut out part of the firewall and make a doggy house in the cab. No big deal. Even with an NV4500 (you'll want an OD for sure) you just won't have room for a reduction box. Not a problem with the stock axle ratio's, however if you drop to 5.43's you have just further reduced the off road and towing capabilities of the vehicle. And on a 6 wheel drive military truck, isn't that the whole point?

The 6bt produces the best mileage at 1700-1800rpm. With the 6.17's this will yield 46mph. Not that great. Switch to 5.43's, and your still only at 51mph. That is a lot of work and money for only a 250rpm reduction. Of course, this is just where it will produce the best mileage and is in no way the top speed. But you go too far out of this power band, and mileage drops.

I had the opportunity to get a 6bt with a Getrag 360 out of a 92 Dodge back when I was looking for a replacement motor. I decided against it for the reasons listed above. It just isn't a suitable swap, atleast for me. And I am not sure how the oil pan clearance would have worked out since I never got that far with it.

I recommend calling Tom at Alfa Heaven. He has done every motor swap imaginable in our little GMC's. His least favorite was the 4bt, for reasons he did not mention. His favorite swap was a 6.2 Diesel and 700r4 with transfer out of any 4x4 GM truck. This setup allows for a very rare combo of excellent streetability and offroadbility. A combo that a lot of people spend a lot of money on to try and get.
 

Section8

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Location
Little Fort, B.C., Canada
I am not really wanting to have to alter the cab if I can get away with it.
I am only considering the 4BT engine since it is relatively ease to increase the horse power on these engines, just the same as a 6BT, it is the short version.
I do have an old GMC duallly 4x4 with a manual tranny in it sitting on my farm, although it needs a head gasket and other issues fixed.
With the swap you described would the front axle chuck need flipping and axles modified to fit in order for proper rotation? Or are most gmc transfer cases counter rotational at front output?
Would it not be simpler to keep the stock transfer case since it divorces from the tranny?
Just have to deal with the loss of low range.
My truck is gonna be more on road than off since it is going to used for hauling my wifes horses and equipment for her business. So not a terribly big loss.
 

Gunfreak25

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Yuma, AZ
The original GMC transfer is always retained for a few reasons. As you said, the front output spins in reverse which is pretty unique for any transfer case, not to mention the rear has two outputs where most only have 1. Not saying it wouldn't work, just would have a lot of disadvantages. The transfer is extremely overbuilt, it will take anything you can throw at it. It does have the permanent 16% underdrive which is even more helpful for towing work.

After a little reading this morning, I think the only way a 4bt would work well would be if you had an OD gear. Without one you will be redlining at 45mph which will just kill any mileage. An nv4500 would allow you to cruise at 55 max which much more appealing. You'll have a 1st gear ratio of 40:1 which is respectable and would take care of anything you needed to do on the farm. Just for comparison, my setup will yield a 120:1 ratio in 1st Low. Quite a spread!

If you are serious about the swap, post lots of pictures! Call Tom at Alfa Heaven
 
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mudguppy

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duncan, sc
you don't want to run the 4bt over 3200 rpm sustained; much more vibration in the 4bt than 6bt.

i would just go w/ the 3200 gov springs; it'll get you the rpm to get to the next gear and will save you from buying HD valve springs. you'll meet your hp goals with a 4bt. heck, in marine trim, the 4bt is rated at 250hp... and we all know that more is available.
 
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