IABDTDOW

I'm currently doing an lt1 swap into my Rx-7 and I have almost everything lined up except for transmission. The engine came out of a 1994 Z28 and made around 380 at the crank. I'm doing a carb conversion on it to get rid of the optispark I don't feel like dealing with. My question is what trans should I use? The engine was originally paired to a 700r4 but I want to go manual. I was thinking a T5 but I can't find what bellhousing to use and a T56 won't fit without major cutting. I can get a T5 out of a 5.0 mustang pretty easily but the bellhousing is still the problem.

NewOrleansLT1

You can try a th350 maybe? But when it comes down to retro fitting sometimes you gotta do what you gotta do and cut..

hrcslam

That t5 will need some serious upgrades to handle the power of an LT1. They ate not very strong. Also the LT1 uses a different clutch set up (puller), so finding anything to work there will be hard pressed as the flywheel is the balancer for the rear of the crank.

Your options are T56 or auto from what I've seen.

96capricemgr

iTrader: (1)

Walk away from the LT1, nothing you have said makes it a reasonable choice.

Puck

iTrader: (17)

I have seen LT1/T56 combos in RX7s before, you can make them fit.

You can go MVB auto if you don't want to retrofit a T56 and still want to have manual shifts, but honestly a T56 is the best fit behind an LT1 so "making" it fit might be worthwhile in the long run.

93M6Formula

Any T5 from an 84-92 (1983 was non hydro clutch) V8 firebird or camaro will work without any modification (V6 cars had lesser spline count input and different bell). He would just need a clutch and flywheel for an 86-92 car since it's the same 1-piece rear seal crank. The flywheel would have to be balanced like an LT1 style though.

But I agree, no T5 will hold up to any good amount of power. Hell they weren't even an option behind a 350 TPI back then.

bufmatmuslepants

iTrader: (3)

If you are going carb ditch the lt1 and go 5.3 or 4.8 or sbc. The only advantage the lt1 had was the fuel injection and ignition, and ripping that out you are left with an sbc with no aftermarket support. The lt1 is a great candidate in that you can get a fuel injected motor, with all wiring harness and PCM and a 4l60e for less than $1000.

Paul Bell

iTrader: (9)

IABDTDOW, welcome to LS1tech!

You'll do better with your questions here in the conversions section.

You don't say how far along you are with this swap but I'd agree with carpicemgr, swapping with any LS engine is a better choice.

https://ls1tech.com/forums/generatio...g-threads.html

Big K

I also am getting rid of my automatic. When I did the motor last year I installed a TH-350 with 3500 stall converter and 4.10 gears in the 10 bolt. I just had Alex from Trick Chassis build me a 9" Ford (narrowed 3") and bought a Currie Nodular third member with 3.75 gears and Strange axles. Running 275/60-15R Nitto 555. The car just spins the Nitto 450's so hard in 1st and 2nd gear and I know with a sticky tire it will hurt the 10bolt. The car is fast but feel like I lose so much HP with the power robbing automatic. I know the T56 is weak kneed as most other Tremic style transmissions. My Dad owns MIDWEST MUNCIE and builds super strong Super M22's and the stronger M23. He has them in a lot of big HP (500plus) Pro Street, Drag Race and road race cars. He is going to build me a M23w (2.56-1st, 1.75-2nd, 1.36-3rd) 4-speed for my 94 LT1 Trans Am. Yes we have it all planned out for the install and it will work and be much stronger than a T56 and you can speed shift a M23 and it will live. Just an option for the automatic blues.