pactheman23

so i just bought a 1975 455 olds got it for 300 bucks with the th400 trans i know anything after 1973 came with a lower compression. the motor was missing the distributor, carb, power steering, exhaust manifold, but who cares for 300 bucks. i checked the oil and there was no slug and the crank turned over. i don't know where to start i want to beef it up but do not have a lot of money. so i need some help guys on what to do

joe_padavano

Actually, everything after 1970 came with lower compression. The only problem with a 1975 455 is the "J" heads, which have the worst-flowing ports of any BBO heads. They are fine if you plan to put this motor in a heavy cruiser, but not so great if you plan to build it for performance.

pactheman23

what are a good set of heads to go with, I want about 500 horses out of the motor when I am done. I see a lot of top end kits for performance, but I don't know if I need to change pistons for compression ratio and cam?

joe_padavano

If you want 500 HP, start by reading the recent articles in Hot Rod magazine about what it really takes to built that much HP into an Olds motor and make it live. They spent $13,000 to get that motor to be reliable.