Swapping a 7.3 IDI to a 6BT 12 Valve Cummins

franklin2

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Here's the deal on the block patterns. Remember Ford is involved in all this.

International had this diesel engine they made (the 6.9, 7.3 idi) that had an international bellhousing pattern. Ford decided they wanted to make a deal and use this engine in their pickups. Ford did make an adapter to mount to the back of the international engine, they all have it. But what did Ford do? They made an adapter from a international pattern to another oddball pattern they made up. Why did they do this? I don't know. But they had to re-tool the c6 castings and get ZF to make a oddball casting just for the oddball diesel pattern they came up with.

Why didn't they make the adapter to use a standard Ford big block pattern? Don't know.
 

Farmer Rock

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Yeah, that's cool man. I'm not dead set on the 5.9. But I would like to do a straight axle swap on the front, and haul logs fully loaded on a 14k-16k gooseneck.

I did look up the banks sidewinder kits, that plus a upgraded pump and injectors would maybe suffice.

I do not want to relocate the Trans. I already shortened my 2 peice shift to fit the GV unit. Any shorter and I'll need to go with a 1 peice shift. So if the 5.9 requires relocation of the drive train, I'll prolly go the turbo route.....

But that 5.9 SOUND!!!! It's screams MURICA
I personally would be more inclined to swap it to a manual whether you go with the Cummins or not. With that kind of load it will really give your ç6 a beating.
What gears do you have?
Are you upgrading the suspension at all?
That's a really heavy load to be regularly towing with a 3/4 ton pickup.
Cummins motors are great, but IMHO, they are better tractor motors than truck motors. I have been around both and truthfully they have no torque curve at all. It's all or nothing, and you don't have any higher rpm range. They are great in tractors and equipment for that reason, but I myself like the power to be spread out. It's not really a matter of Cummins vs IDI, but more I6 vs V8. It depends on where you want the power to be. IDIs are basically like a 2 stroke Detroit ( screaming Jimmy) , but obviously IDIs are 4 stroke, so they actually have a much wider rpm band in comparison.
I am in no way trying to turn you away from a Cummins, just pointing out a few things.
The truth is though, I think you would at least need a 1ton drw for that load. While, you could make your truck a dually, is it worth all that? You may be better off keeping this truck the way it is and buying a cheap 1 ton, either with a Cummins, or a Ford you can swap one into, and using that for a dedicated tow rig. Just my $0.02


Rock
 

u2slow

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I personally would be more inclined to swap it to a manual whether you go with the Cummins or not. With that kind of load it will really give your ç6 a beating.
What gears do you have?
Are you upgrading the suspension at all?
That's a really heavy load to be regularly towing with a 3/4 ton pickup.
Agreed on the manual.

Most 3/4 and 1-ton pickup frames are the same. Springs, tires, axle ratios are easily upgraded. I haul 2-tons payload in my '250' whenever I feel like it. The real difference is the GVWR tag, so what may be legal for the 1ton DRW isn't legal for the 3/4-ton. The cab & chassis frames are much more capable of regular heavy hauling.

Here's the deal on the block patterns. Remember Ford is involved in all this.

International had this diesel engine they made (the 6.9, 7.3 idi) that had an international bellhousing pattern. Ford decided they wanted to make a deal and use this engine in their pickups. Ford did make an adapter to mount to the back of the international engine, they all have it. But what did Ford do? They made an adapter from a international pattern to another oddball pattern they made up. Why did they do this? I don't know. But they had to re-tool the c6 castings and get ZF to make a oddball casting just for the oddball diesel pattern they came up with.

Why didn't they make the adapter to use a standard Ford big block pattern? Don't know.
I don't understand either... perhaps they intended to use the bigblock pattern for chassis fitment and production-line tooling, but ran into some other snag later in development? Then for International to adopt this new Ford pattern into the subsequent 7.3PSD block, and then abandon it for the 6.0L ...cookoo

Dodge isn't much better - creating a unique pattern for the cummins that wasn't bigblock or SAE. I don't know if they've changed it since the original in '89.
 

catbird7

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I looked into the Cummins swap for my truck several years ago and while I didn't do it I'm a Cummins fan! Power potential of ****** vs IDI , Cummins wins every time! Seem to remember doing the math regarding cost and the most logical combination was Cummins engine and Doge trans. The cost of bell housing adapter itself was the price of a used tranny. Cummins engine, Dodge tranny, a set of conversion motor mounts and two custom driveshafts and you're basically done. Another route to consider is 24 valve Cummins (sweet engine) all the power plus good fuel economy. And I gotta say this, love that Cummins sound!
 
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