|Copied from HotRodders.com|
This is what I will be doing. It looks like the best HP for the $$. Combine that with a streetable cam, dual exhaust, and a 4 barrel carb. Seems like the way to go. Get some extra HP by using electric fuel pump and/or electric fans. Get a better HP to Weight ratio by making the car a little lighter.
Aliminum- intake, radiator, core support, hood, bumper supports, bumper brackets, wheels, rear brake drums, etc.
Use a mini starter for less weight.
i ve built a few 350 headed 403 they are powerfull and yea they are a small bock olds did make a big block 400 425 455 and the heads will interchange
ok but back to the 350 being a 70 they should be casting no 6 5 6 and 7 are the best ok first u need to drill the head bolt holes to fit the 403 head bolts
2nd use 403 intake vavles NEVER USE THE 455 2.07 the 403 intake valve is 2.00 the smaller cc should bring a stock 403 to 9.2-9.5 compression and any intake will bolt on to it u can use 455 heads but u need a ported performer rpm intake and flat top pistons the 455 have the same cc as the 403 so it wouldnt increase compression like the 350 heads do with out porting or any other mods expect 50-70 hp more withe the 350 heads on your 403