This 1 inch tall phenolic thermoset plastic spacer insulates your carburetor against manifold heat keeping it cooler and helps prevent fuel percolation (also known as vapor lock) in hot weather. This can also allow for a denser fuel mixure to help increase performance in some applications, as well as provide additional plenum volume. 4-hole design fits Holley 4150/4160 4-barrel carbs as well as most Carter and Edelbrock models with a squarebore design. Gasket, studs, washers and nuts are included.

Product Features:

• Phenolic Thermoset plastic insulates against manifold heat
• Keeps fuel cooler to reduce vapor lock & increase charge density
• 1" height increases plenum volume
• May increase performance in some applications
• Gaskets & installation hardware included