Hey guys,

I am considering doing an LS swap on my 64 Cutlass. It currently has a TH350 in it that can't hold fluid. Is there a cheap manual transmission that would be worth using? The ones coming out of newer Camaros and Corvettes all seem to be $1500+. Are the gear ratios in a truck transmission unusable in a muscle car?

Thanks,

-Mike

 

You can run a Muncie or T10. They can be found for a few hundred and will require a $100 rebuild kit.
As for OD trans, the T5 is probably cheapest, but not very strong. And the easiest would be from a V8 3rd gen F body, but those are pretty old and most in bad shape.
The truck trans generally have a really deep 1st gear, some in the 4-6:1 range.
What's your current rear end ratio and what do you plan on doing with the car?

 

I have a 10 bolt rear end but haven't opened it up yet to see what's inside. I plan on using the car as a weekend cruiser and to take to work once in a while. I want the car to be safe, reliable, and fast on a modest budget.

 

If you have a 3.08 or higher rear look for a wide ratio Muncie or super T10. They have around a 2.6 1st gear. Probably not worth the added expense of OD to save a few bucks on gas.
Also, most of these older cars require tunnel cutting for a T56.
Are you looking at an aluminum block or a 5.3/6.0 truck iron block?

 

I'm looking at a 5.3 from a 2004 Silverado and I plan on replacing the cam with a LS1 cam and some flat top pistons from a 4.8. The one I'm looking at has 168k and will run me $540.

 

I'm running an 05 5.3 in my 72. Nice combo for power and cost.
Try to get the harness, ecu, sensors, accessories...everything you can with it. Piecing together all the parts needed gets expensive.

 

Is there a way to tell which gears I have besides taking the rear end apart?

 

e rear tires off the ground, rotate the driveshaft till the wheels make 1 revolution.
You should be able to count the number of driveshaft turns. Just over 3 =3.08
There's also a code on the right front of the axle (I think). Google axle codes for ratio.

 

Thanks, I'll check that out.

 

Figure out your rear end ratio. Then pick a trans to fit.
3.08+ you can use a wide ratio Muncie/T10 (2.6 1st gear). Under that, you can use corvette super T10 (2.88 1st) or a Camaro T10 (3.42 1st).
And everything you need to know about hooking a Muncie/T10 to an LS motor:
http://ls1tech.com/forums/conversion...-ls-motor.html