You should talk to a pro engine builder. 450-500 is way too much to expect with that set up. Check out this site
www.golensengineservice.com see what the're using to make 450-500. Give them a call or e-mail if you have questions about the custom projects they do. I'm trying to save some money and have them build a 450hp 351. Good luck with the motor!
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1995 GT Black sleeper
Edelbrock 6037 heads,Edelbrock proformer intake,Edelbrock cam, 70mm TB,75mm pro-m mass air,Taylor wires, Underdrive pulleys,Equal length headers,K&N filter
Flowmaster cat-back, Eibach pro rate springs
lower control arms
3.73 gear Centerforce clutch