question: from 366 gas to 6.5L

[machavis]

I got a killer deal on a '93 GMC C6000 cab and chassis. Basically if you can haul it you can have it. The bad news is it has a 366 gas motor with an Allison AT545. It's an under powered turd, to say the least. My question is: Will a '92 6.5L bolt to the Allison transmission? What else is in volved with the swap. Torque converter, engine mounts, ect...
I have visions of this becoming a welding - service truck. So I'm not worried about speed, just want to be able to get out of my own way and better fuel economy would be nice.
Any advice would be greatly appricated.

Mike

[Robyn]

The 6.5 should bolt up to the allison using the same flex plate as the 4L80

The 366 is just a small bore big block.
These were used in a lot of medium duty trucks for many years. IIRC these are a tall deck engine too.

The bell housing bolt pattern is the same old chevy tricks. The motor mounts should be fine too.

The accessories from the 6.5 will be needed to complete the install along with the 6.5 radiator from the diesel.

Most all of this stuff should bolt right in.

use a mechanical pump on the 6.5 and you should do fine.

Now is the allison electronic??? of so the adaptation could take on other issues.

More info please.


Missy

[dieseldummy]

I have a friend doing this very conversion right now. The allison will most likely have an SAE bellhousing with an adapter plate to the standard chevy pattern. That's how his 5 speed was. I don't know what kind of flexplate the allison will have, but it is possible there will be problems getting the starter to fit. You will have to fab up some motor mounts since they use a standard medium duty setup with a mount of the front of the motor and two on the sides of the transmission. The accesories will also require some special consideration.

[turbonator]

we are currently doing the same swap, the truck came with only the 350 though.

we did our 6.5l with arp head studs, 60 thou cometic head gaskets, and full main girdle on all 5 main caps.

we are using a holset he-351 vgt turbo, with intercooler a water-methyl injection, we are hoping to push 15-18 psi boost, our tranny will be a sm-465, hoping to find a ranger o-d gear-box.

one question i have at this time is will the small-block fly-wheel match up to the 6.5l, thanks in advance for the advice.:)