CNC Ported AFR Cathedral Port, 6-Bolt LS Cylinder Heads - Assembled

These AFR cathedral port heads bring a lot to the party with their 6-bolt design. We buy these heads as porter castings and machine them to perfection on our CNCs.  The shapes we impart to the ports and combustion chambers reflect our years of experience on our own engine builds.  We know what makes power and also survives the beating of competition.  It's not chasing peak air flow at max lift by excessively cutting away the metal around the valve guides. Peak air flow occurs at only one instant in the cycle. Our focus is more on average air flow across the entire cycle. For spring packages with 0.650 inch max-lift, quoting a peak airflow at 0.800 inches is irrelevant. Of paramount importance for us is that our cylinder heads don't break and wreck our engines.  We therefore do not chase flow at the expense of weakening the heads mechanical integrity. That's a concern that non-engine builders don't share.  Our process for machining heads includes CNC porting and combustion chamber mach