I have a Rockland Tranzilla with the ZR1 gearing and can say the trans shifts like no other T56 I have driven and so far has had no problems taking the beating of road racing it. My experience so far has been trying to find a clutch that's streetable that will live any length of time is a bigger problem.

As far as I know a 6060 and a Magnum are the same trans. (as in, I thought all Magnum's were 6060's and not T56's).

Now a 6060/Magnum over a T56? There are many internal upgrades the most important of which that pertains to you is stronger gear sets.

I've found it's easy to strip the teeth off of the input shaft and countershaft of the old T56 with over 800ft/lbs of torque.

RPM is an excellent choice for the 6060. They built the one in my twin turbo 07 Z06 and it always worked perfectly.

Don't mean to highjack your thread but I thought my thoughts and questions might help someone make a decision.

Great thread. You've all helped me make the decision for a T56 Mag in the Corvette config. With 275/40s looks like the 2.66/.50 may be better suited for 4.10 and the 2.29/.67 better suited for 3.73 for the street. Both will place my cruise RPMs at 2200 at 55MPH in 5th and 2000-2200 at freeway speed which sounds great. But what about track? I have no track experience but hope to soon. The car will have 396 but I'm now leaning toward a built LS primarily for weight reduction. Any thoughts would be appreciated.

David