olds 403

[79tenthanniversary]

can anyone tell me whether or not i can use a set of 1967 olds 330 64 c.c heads on my 1979 olds 403,and if so what modifications will i have to make

[maxwedge]

Welcome to AF, no sure if they fit I don't believe they do plus no performance advantage here, very small port head, maybe some compression.

[carnuted]

The best head would depend on what you are doing with the engine. If the engine is stock and you are just looking for a compression boost, 68-70 heads would be your best bet. Problem is those heads did not have hardened seats, so unless they have been rebuilt and had hard seats installed, you should stay away from them unless you want to spend the money yourself to have it done. Heads began coming with hard seats in 71-72, but they also came with larger chambers, so not much compression help there. Big block heads will fit on a small block if you use an aftermarket intake, but you will lose compression there, but if you are going through the motor and installing different pistons, than that could work for you. Let us know what you are working with and using it for, and we may be able to help you a little better.