I think the T5 WC tranny can handle the torque/HP that a 5.7L puts out (stock that is)... reason I say this is that I know of two people that have transplanted a 350 into a Camaro that has a T5 WC...no special tranny... just dropped in the motor... and they drive 'em hard too!! Tranny from what I am told is holding up fine.

I think the reaosn for the no T5-350 combo in the F-Body is more to due with the Corvette of the 80's... a T5-350 Camaro would have lured too many potential Corvette buyers away from that market... I dunno...just a theory.

 

the way i have understood it, hopefully someone will correct me if i'm making an error. The T-5 and the WC T-5 are two different transmissions, the wc t-5 is built up a little bit more.