i have a 89 camaro with a bad 700r4 and i want to put th35o, what kind of modification will i need to do, will i need a diff drive shaft, ect, tahsnk

 

If you use a long tail (9 inch 350) you can use th original drive shaft if not you will have to shorten drive shaft three inches. you will need to move cross member and relocate the torque arm. May I ask why you are switching to a 350 your going to loose alot drivability wise.

 

cuz i already been through 3 7oor4 my car is 470hp on motor and i also i have a 125 hp on nitprus, so im looking for something strong

 

Well a TH350 is IMO not alot stronger than a 700r4 have you gotten a trans from a sponsor here or someone who specilazes in built 700r4 transmissions?