which carb spacer

[72golddustermike]

wondering which spacer to run

setup on 76 360
.40 bore 9.5 compression
edelbrock performer heads
comp cams thumpr cam
edelbrock performer intake duel plane
quickfuel ss 650 DP

 

[rumblefish360]

Which Thumper cam and style?

IMO, the intake is limiting if the cam is sizable. IF any thing, a spacer is a crap shoot. I think I would try a 1 inch 4 hole spacer.