I have an Olds engine with #3 cast in the center exhaust port. Can anyone tell me what this is? It has larger valve springs than a #2 head. I can't find any info on a #3....lots of #10 info. Would this head have a better compression ratio than a #2? What year is it? Anything is better than what I know now. (it is a '50's engine of some kind..303, 324??) Thanks!!!!!
It's a '53 303 head. Like you said, SBC diameter springs instead of the tiny springs on earlier heads, and a smaller combustion chamber. I think the factory compression rating was 8.25:1, as opposed to 7.25 or 7.5:1 on the no number and #2 heads.
The Jalopy Journal
