I need help guys. I have a 85 transam Tpi and I just dropped a 87 firebird 350 crate motor into it. She runs good until i ride on street for more than10min then she gets up to 220-235 degrees which I know is bad. I have a new stock radiator,185 degree therm, Im not loosin coolant and I just got the system flushed. Do you think the water pump is to blame. Also which stock 305 parts do i need to change to better upgrade and benefit the new 350's performance. Shes not giving me the power I know she has like something is holding her back. I heard I need to change the 305 fuel injectors to 350 fuel injectors is this true. Any help is highly appreciated. Thanks

 

I had the same problem with a 91 firebird. I put in a radiator and twin fan setup out of a ls1 trans am. The exhaust is also causing some of it if it's stock manifolds and restrictive pipes. They don't even flow good for a 305.

Depending on the engine, gears are always good. I would either try a shift kit or build up the tranny(don't use b&m). If you drive hard a posi is a must with the new found horsepower.

As for the fuel injection i would put in 350 injectors and a custom chip burned for your cam.... you can try tbi.com

Good luck,
Doc

 

230 isn't out of the ordinary for these cars, just so it isn't going much higher.. just make sure you have all the air out of the cooling system and the level full. Make sure your fan(s) work, make sure you lower air dam is still in place and you have the correct water pump. FYI serp systems use a reverse flow water pump, v-belt setups use standard flow. As far as power as mentioned above make sure you have a free flowing exhaust system as they are the biggest limiting factor on these cars from the factory. Injectors may help but I wouldn't expect a HUGE gain from changin em or anything.. was this crate engine just a stock rebuild?

 

IIRC the knock sensor is also different between the 305 and the 350.