You are going to have a clusterf*** getting all of that to work together. You're putting an engine that's a lower torque, higher RPM performance engine into a truck with a transmission built and geared for a low revving diesel. Physically installing it will be the least of your worries.
Now, the Allison 1000 transmission was a 5 speed, not a 6 speed, up until 2006. Here's a problem: The Allison is rated for a MAX input (engine) RPM of 5000. SPin over that, and you're asking for trouble. It's a heavy duty transmission for low revving diesels.
So you would need a transmission controller to make it work, plus all the wiring that comes with that. You would need to get a bellhousing adapter, a custom flexplate to mate the smallblock chevy engine to the allison torque converter. You would need a way to adapt the linkage for the shifter to the transmission.
Anything can be done...but from reading about it, it sounds like more work than it's worth.
To be honest, this sounds like a very poorly thought out swap. Not to be mean, but just because you have the parts laying around doesn't mean it's the best way to do something. You might have a ford engine and a chev transmission, just go buy the ford transmission.
A 327 is not a truck motor. Small displacement equals no torque. A 350 is barely a truck motor, and until they put Vortec heads on the small block they really weren't good either. The new LS motors are better, but the best ones are larger than 5.7 liter.
The allison transmission is massive. The parasitic drag of that transmission will take probably at a minimum 25% of the output of the 327. Not only that, but it weighs a ton as well. Fitting it in the '89 is likely to be a problem in itself, requiring a body lift of substantial proportions.
On top of that, have you priced out either standalone TCU's, or even manual valve bodies for the later automatics? The TCU's are easily over $1000 for a later *4 speed* auto like the 4L80E, which would be the smart swap if you need the heavier duty trans.
Injecting a 327 wouldn't be that tough, but it wouldn't be smart. Probably a small journal 327 too is my guess.
actualy yes It can be done.. but its not easy..... I couldn ;t even begin to write the steps. do you realize all the work involved in this... The Allison also uses a 29 spline output (bigger than the 32 spline) and there arent many t-cases that work with that. It can be done, and we have the parts for the most part, just realize that its an issue to where your getting into changing parts more indebtfully but it can be done still... the crankshaft flange is different. I think theres an adapter needed for correct torque converter spacing. i figure the computer will be a fun task as you pointed out... ive seen them in big blocks with adapter plate meaning they will fit a small block for sure cause big blocks and small block chevy used the same bell housing,. it can be done definitely. just its going to be step by step and a good project. you would be one of a kind thats for sure.
if anyone see's ive mentioned some thing incorrectly please correct me politely. am thinking from memory. but still it could work... but could you do it? its a big task.... not a simple swap. id assume with the adapter plates it will also need to do some modifying for the driveshaft.. most definitely moving the transmission cross member... ontop of if im not mistaken the Allison requires a 3 inch body lift for clearance.. i think. could be wrong but that's what i think.
First of all, LOSE the computer, 66 327CID ain't gonna want it, unless you're going FI vs. carburated. Allison valve body mods.will eliminate need for ECU, also. Then is just about adapting bellhousing to block, and converter to flex-plate. Transfer case to tranny can be done w/ fabbed adapter snout and stub shaft. James had it covered, sounds like a fun build.
I have a 1966 327 chevy engine. I also have a allison 6 speed trans off of a 2002 4x4 chevy duramax diesel. My question is, can I get an adaptor to bolt the torque convertor and trans up to that old motor? Also, what will I run into as far as the computer goes? Doesn't it shift off the computer? All of this would be going back into a 1989 4x4 3/4 ton chevy. Can it be done?
