Some of them are adjustable. The inlet fitting screws out & you can add or remove shims to adjust the rate of advance & shorten the spacer to get more advance. The pcv system should not effect the vacuum unless they are hooked in the same outlet.


They say money can't buy happiness. It can buy old Chevy trucks though. Same thing.
1972 Chevy c10 Cheyenne Super
In the Gallery Forum