Well, Im considering the swap of a 400 small block from a 305ci and I was wondering if my M5 trans could hold up. It will probably have mild aftermarket parts (headers, 750carb, mild cam,etc.). Will the M5 be a problem?

 

The T5 tranny will last approximately 2 seconds from the time you punch the throttle on the 400.

 

Well, To be expected i guess. What kind of potential does the T5 have?

 

Expect it to be reliable up to 300 Hp. After that you're on your own. There are success stories clean up to 350 Hp... and then there are the abundance of the 'other' stories. You can pick up a Tremec 3550 5-speed for a 3rd gen Camaro for about $1300. I'm not sure but the last time I checked that was quite a bit cheaper than the Richmond 5-speed.

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'89 Firebird, RED!!!
B&M blown 468 big block
Tremec TKO 5-speed
Strange 12-bolt
Kenny Brown Competition Suspension
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