Zipper’s Stage 4 CNC for 06+ TC w/ACR

The largest port we can machine into these O.E castings is what
you get with Stage 4. O.S. 2.00” Valves, Step Lock Guides, special valve seats,
5/16” valve springs allow up to .750” of cam lift. Max flow design for big
displacement engines with large airflow demand. The larger valves are completely
un-shrouded in the fully machined chambers. Combustion Chambers are 98 cc.

*Not Available for Twin Cooled models.

Weight1 lbs
Dimensions1 × 1 × 1 in
Engine Type