Just wondering about T-5 tranny rebuilds. I have a non-world class tranny and 3.08 gear in the Formula. Questions:

I like the .63 overdrive gear, but might want to run the taller 3.35? 1st gear with the 3.08 rear. Is this possible to swap gears/parts between non-world class and world class T-5's?

Are any custom gear sets available for the GM version of the T-5? I would love to have the six-speed .50 5th gear if I could get it, any hope of this? I could run a 4.10-4.56 gear and still keep my mileage.

 

You're basically looking for features of the T56 (wide overall gear spread) without getting a T56, but you want to spend a lot of time and money on parts for the T5.

You can gear a T5 differently but it's gonna cost a good bit of money in parts, and you'll end up with a weaker trans. The case, gearsets, mainshaft are different between WC & non WC, so that won't fly unfortunately.

All things considered the 3.35 first gear to second gear drop is excessive; the 2.95 is better suited to a V8. And if your 4th gear is 1:1 (it is by design and not changeable,) and your 5th were .50, the drop would be crazy and annoying & jerky, even on the hwy.

GM put a good bit of time into choosing the 2.95 / .63 gearset for some of the V8 f-bodies and they work damn well.

Save your bucks and get the T56. Worth it.

 

The parts you would want to swap between a WC and NWC can't be swapped. The gears themselves are different, because NWC ran the gears right on the mainshaft, but WC had caged needled bearings under the gears. The setup you want is a GM WC T5 with 2.95/1.94/1.34/1:1 1st-4th gear set and then use a 0.63:1 5th. This gives the best gear spread for performance use. I would say run 3.73s with that combo and you will be very happy.

Your options are basically get a WC T5, which can be upgraded for additional power if needed, or go with a T56 or Tremec. Factors to consider are how much power does your car make? How do you drive/use the car? How much can you afford to spend? The answers to those questions will basically make the decision for you.