I want to do a 350 swap and rite now i have a completly stock 4 speed auto 700R4 with 79000 miles on it. If i do the engine swap and the 350 im gonna get puts out anywhere from 300-350 hp will my stock tranny be able to take this power. I've heard both answers but i kinda nead one solid definate answer. Thanks guys.

 

IMO.... No. i dont think so, because the same tranny was in the 350 TPI cars that put out like 245 HP, and they always needed rebuilds with corvette servos, which depending on the shop can cost up to $2000. but thats just my experience. yours might be different. the 4L60E might be stronger im not sure, but if your gonna do a swap anyways, you should check out a salvage yard for a 4th gen with an LT1- 4L60E combo with acceptable miles.

 

that 700r4 will be toasted. i had a +/-300 hp 400 small block in a 84 firebird, and when i put the engine in, and i threw it in reverse to back out of the driveway, and the trans **** right then, i couldnt even test drive it.

 

Yeah i highly doubt that trans will hold up to that power, but try it anyways... and when it goes out, rebuild with shift kit and stall and you will be good to go.

 

Sorry to but into your post but i was going to ask the same question but about a tbi gm performance parts 350 which im guessing has around 280 horse. I have the same stock tranny with a tbi 305 in now. Also the rear end will be a 3.23 out of a v6 3rd gen which i know will be ok.