Yella Terra Alloy 6 Heads
Choose the right rocker type for your application. CLICK HERE!
Yella Terra cylinder heads are machined and tapped to 7/16 UNC as standard to suit shaft-style rocker systems. If you intend to run 5/16 shaft rockers, the appropriate Yella Terra 7/16 to 5/16 adaptors must be used to correctly convert the rocker mounting interface. These adaptors, identified by the relevant (A) part numbers, allow 5/16 rockers to be securely installed on heads prepared for 7/16 hardware, ensuring correct fitment, strength, and alignment without further machining.