Extends length of intake mixture column to improve air/fuel distribution CNC machined from 6061-T6 billet aluminum to extremely accurate specifications Billet aluminum eliminates porosity and improves engine appearance Available with 4150/4160 and 4500 Series Holley® bolt patterns to fit a variety of carburetors 4150/4160 Series Spacers available in 1/2", 1" and 2" thicknesses with open plenum and 4-hole designs to suit tuning requirements; 4500 Series (Dominator) Spacer is 1" thick with open plenum As a general rule, open designs increase plenum volume for improved high rpm power, while 4-hole designs increase mixture velocity for improved low-speed and mid-range torque

Unique 1/2" spacers are precision machined on state-of-the-art millworking centers, and can be used individually or stacked without the use of gaskets Thin layers of choice laminated hardwood, bonded together with resin form a natural heat sink Top-quality hardwood has a sheet of phenolic resin-impregnated paper bonded to both sides Can be easily modified to your particular manifold for optimum performance

Can easily be mounted with one of the Moroso Carburetor Stud Kits No. 37950, 37960 or 37961 Open plenum aluminum carb spacers increase plenum volume for high RPM power Four-hole carb spacers increase mixture velocity for more midrange torque

Advanced plastic and phenolic compounds are specially formulated to reduce heat conductivity 10 times greater than aluminum Reducing fuel temperature inside the carburetor results in a denser, more powerful fuel charge to the manifold Insulating phenolic spacers come pre-drilled for alignment pins and Nos. 64930 and 64940 include all mounting hardware Gaskets not included