okay, i have a v6 right now and am swapping in a v8 (with a 700r4). the new motor and tranny came out of the same car and the tranny was allegedly rebuilt ~8000 miles ago before i took it out. both came out of an 85 caprice.

i'm in the middle of a block-up rebuild on this motor. the only stock parts in it anymore are the connecting rods and the flexplate. I'm giving a ballpark estimate of 300-350 horsepower when it's all back together.

do i need to upgrade the gears in this tranny to keep from blowing it up? my driving style is fairly aggressive, and i plan to take it to the racetrack two or three times a month.

also, when i was searching for the answer to my question, i found a topic that mentioned if you have your foot it it at all (at highway speeds) and it drops into passing gear (3rd) it won't shift back into 4th until you come off it almost all the way or something... (i notice my car doing this but since the v6 is nearly dead and gutless under the best of conditions i thought it was just cause my motor didn't have the torque to get into 4th at 80) what would i need to do to this tranny to get it to make every shift at 5000 under WOT conditions and treat itself as a four-speed auto, instead of a three-speed w/od?

thanks for any help