Heads are the most important part of the build. Better get them right.

For this build we are going to use a set of L31 Vortec Heads. This is because;

• Rulebook – “Cylinder heads must be OEM production”, “Cast Iron heads only”
• The L31 Vortec head is the best flowing head produced by GM.
• The combustion chamber is more efficient than the standard wedge chamber of earlier GM heads.