So I just had the clutch replaced in my 85 Trans am and it is seeping fluid from around the countershaft bearing so I assume the case is stretching and I need to upgrade. Since I just dumped a decent amount of money into my new clutch and flywheel I'd really prefer to keep them. That leaves me with the tko600 bolt in kit from Fortes for a little over $3k or possibly an ls1 t56 with the adapter and pilot bushing to use my bellhousing. Is this t56 adapter combo as simple as I think it is? Seem like it could be the cheapest/easiest way to a t56 with just a $300 adapter and a new crossmember needed. What am I missing?

 

Been doing a lot of research on these two options myself.

Biggest issue with the LS1 transmission adapter route seems to be that nobody makes a crossmember that is direct fit and the need to shorten the driveshaft, torque arm and rework the shifter so it ends up in the correct spot in the console. Dyno Don talks about this in his experiences with the LS1 to SBC swap here. https://www.thirdgen.org/forums/tran...ml#post2292629

The TKO route seems to be closer to a "bolt in" solution with minimal (if any) fabrication needed.

I would be very interested (and grateful) if you would share the details of whatever you end up going with and how easily (or not) it ends up fitting into the car.

 

Well stated.
And you'll need to shim the slave cylinder to release the T5 clutch. And your speedometer drive will need an adapter.

For a SBC, the LT1 T56 is still one of the simplest options. If you really want to keep your clutch, you can run an LS1 front plate and slave, but may need to machine it down a bit. Ultimately, the LT1 clutch is simpler to just go with. And the 94-97 box can go LS1 later, if desired.

There are a lot of ways to make a lot of transmission options work just fine. You just gotta make a costlist of all the little details. Otherwise your $300 swap is going to fool you into thinking it's accurate and . . . it's far from it.

 

Oh I didn't even think about needing to shorten the torque arm or the shifter position issues with the ls1 set up! I'll have to do some figuring on all the lengths and see if it is something I can accomplish myself. I'll also go through and do a thorough cost analysis for each setup and make sure I'm not throwing money away to try and save my clutch

 

You stated it perfectly. I was hellbent to use an LT1 T56 with a T5 clutch and mechanical linkage. I did, but it didn't do anything quantifiably better than an LT1 clutch and hydros. It just worked normally.

 

Out of curiosity, what did you do to make that work?

 

The throwout bearing sleeve o.d. was increased so it matched a T5.
I added a ballstud to match the 82-83-F-body / 78-81-A-body fork ballstud location.
Some cutting . . .
Used an aftermarket fork for 82-83 F.
The clutch kit and fork are standard third gen stuff.
And I didn't have to cut my driveshaft, which was compatible with my prior T5 and my other car's 700-R4..