Cummins conversion

BrandonMag

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I picked up a Cummins out of an '89 W350 4X4 about a month ago and am planning on dropping it in the '85 F350 in my signature. The plan is to use primarily as a tow rig... the '89 F250 I'm currently using for that purpose is a bit lacking in the power department. Plus, I'd like to get better than 9 mpg when towing. From what I've read, a 6BT should solve both of those problems.

The F350 came with a bad 460 backed by a C6. Seeing as how I'm planning on using this to mostly drive down the freeway, what would be the best tranny to put behind this Cummins? Would I be better off keeping the C6 and using a GV behind it or going with a ZF 5-speed? (I can get a ZF for a pretty reasonable price.) Or would I be better off with some other transmission?

Regarding the Cummins itself: this is a factory non-intercooled VE-pumped motor. It has about 175K on it and I'd like to put out about 300 hp with it. Can I realistically put out that much power with a VE pump? Can I have the injectors that came with my engine rebuilt by a reputable shop to put out that kind of power? What is the limit on hp by the H1C Holset turbo that's on the engine now?

There's a factory tranny cooler on the passenger side of the motor for the Dodge 727 trans that the W350 came with. I'd like to eliminate it. Is there a block-off kit available for this purpose?

I picked up the Cummins service manual for this engine (it's two volumes and weighs about eight pounds) and have started reading it. Quite a bit different than the International 7.3 IDI I've had for the past couple of years. Any experience/pointers is appreciated.

If there's a better bulletin board for these questions, please share.
 

MIDNIGHT RIDER

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There ain't the most traffic here, as you have probably fugured out.

I will try to give a few answers to your questions.

Also, you can follow along in the IDI section with a Cummins swap thread recently started by 93-444-IDI or somesuch; just about anything you will run into is already being covered there.


http://www.oilburners.net/forums/showthread.php?t=50937

I would avoid using the ZF transmission; there are many better easier choices.

For a 5-speed, the Getrag G360 that came on the 1989-93 Dodge/Cummins is the best choice, unless you hit the medium-duty junk-yards and come up with the correct SAE adapter and a Clark or Spicer.

The NV4500 has plenty of problems and it is my understanding that NV is now defunct.


If you are used to towing with any of the IDIs, in bone stock form, with nary a fuel-screw turned, that 1989 6BT is going to make you think you have a jet airplane engine under the hood.

The H1C will support enough horse-power to keep you happy, but some of the bigger units will bring down long grade EGTs.


As for the transmission cooler, so far as I know, it just hangs on the side of the engine and can be removed without much hassle.

There are some heater-hoses plumbed in and out of it.

Unlike the Stanadyne on the IDIs, the BOSCH VE is simple to tune.

With no more than a 12MM wrench and a straight screw-driver, you can really wake them up.

Also, unlike the P7100 pumps on the 2nd Gen.s, you can crank up the power without blacking out the neighborhood.

There are several different governor springs available; factory-issue is 2700-RPM; then there are 3200, 3600, 4000, and even 5000 and 6000.

For improved drivability, most opt for the 366 spring which is the 3200-RPM unit.

But save that for later; that 6BT in unmolested form is gonna impress you plenty as is.
;Sweet
 

rebel_horseman

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The F350 came with a bad 460 backed by a C6. Seeing as how I'm planning on using this to mostly drive down the freeway, what would be the best tranny to put behind this Cummins? Would I be better off keeping the C6 and using a GV behind it or going with a ZF 5-speed? (I can get a ZF for a pretty reasonable price.) Or would I be better off with some other transmission?
Honesty, for towing I'd only have a manual transmission. I just like picking my own gears, having less parasitic loss from the torque converter, and better fuel mileage. I love the G360 as the gear spacing works great with the 6BT. Make sure if you go with it you overfill the trannie with an extra quart of 5w30.

Regarding the Cummins itself: this is a factory non-intercooled VE-pumped motor. It has about 175K on it and I'd like to put out about 300 hp with it. Can I realistically put out that much power with a VE pump? Can I have the injectors that came with my engine rebuilt by a reputable shop to put out that kind of power? What is the limit on hp by the H1C Holset turbo that's on the engine now?
300 RWHP is easy as pie with these engines. Don't worry about the injectors; they are perfectly fine for what you want to do in stock form. You can turn up the engine power using only common hand tools. I would recommend installing a 3200 RPM governor spring then adjusting the pump and bumping the timing. The H1C is an OK turbo but the compressor housing is a 18 cm2 meaning it's laggy as hell. You can swap the housing for a smaller one which will help dramatically. That's going to be my next upgrade on my '93.

There's a factory tranny cooler on the passenger side of the motor for the Dodge 727 trans that the W350 came with. I'd like to eliminate it. Is there a block-off kit available for this purpose?
As far as I know, there is no trannie cooler integrated into the engine; it was located in front of the radiator. It's possible that it's something else, or someone relocated it there. Where is the cooler at and are there any lines running to/from it?

If there's a better bulletin board for these questions, please share.
I'm a member of Cummins Forum as well as 1stGen.org. Both are great sites with great information.
 

MIDNIGHT RIDER

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As far as I know, there is no trannie cooler integrated into the engine; it was located in front of the radiator. It's possible that it's something else, or someone relocated it there. Where is the cooler at and are there any lines running to/from it?


horseman,

The next time you are around an automatic 1st Gen., have a look under the hood.

Whereas, a manual truck will have only the two heater-hoses and the steel-tubes that run along above the exhaust manifold; the automatics will have more of the steel tubes down low on the steerboard side, plus a bunch of little 90* hoses, plus a big transmission/coolant exchange unit, mounted down under the turbo.

Those units must be pretty long-lived and problem-free, as I never see them discussed.

I sort of think they also have the standard in-the-radiator cooler common to most automatics.

 

rebel_horseman

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It sounds vaguely familiar. I could have swore that the only cooler was in front of the radiator but now that you mention it, I have some recollection of someone mentioning an integral block cooler.
 

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