In my opinion the TH-350 was darn near bullet proof but recently I got my hands on an 87 Pontiac Firebird Formula with an LG4 and 700R4. When the 305 goes I’ve got my eyes on a 350 but I’m wondering how much horsepower I can go up to before I have to start worrying about the stock tranny. Any advice, experience or tips to pass along? Thanks!

 

'87 was the year that upgrades were made to the 700R-4 from previous years. I wish mine was a '87 (it's a '84)...

 

Remember back in the 90's when the 700R4 was the 4spd auto to have? Along with the 2004r, and 4L80? There was a long period of time when those transmissions were the hot ticket. No clue where the stock limit is, probably close to the stock limit of the TH350.