Description: Some of these heads are not Closed Chamber Heads like the 1967 670 cylinder heads. They were like a Semi Open Chamber Design. I have seen this before. As Pontiac was learning about the propensity to cheapen the fuel changes had to be made
Some of these heads are not Closed Chamber Heads like the 1967 670 cylinder heads. They were like a Semi Open Chamber Design. I have seen this before. As Pontiac was learning about the propensity to cheapen the fuel changes had to be made
