This spacer will allow easy connection to vital manifold vacuum readings which are required when tuning a carbureted engine.
Many new racing carburetors do not have vacuum ports, so alot of tuners face quite a challenge to easily connect instrumentation to these engines... UNTIL NOW!
These spacers are thin enough (.125) that engine performance is not altered when the spacer is added, and no changes should be required to the existing carb stud length.
This spacer will NOT work for power brake or PCV valve.
Available for: Holley 4 Barrel (4150 & 4500), Holley 2 Barrel, Rochestor 2G
Ultra-Thin Carburetor Spacer with Boost / Vacuum Port
Your choice @ $70 each