magnum head porting / pushrod pinch area / etc

I think it was the Engine Masters magazine (I will check and see if I still have it) did an article on porting magnum heads. They took it through steps and flow checked it after it step.

They did the simple stuff; multi angle valve job, bowl blend, streamlined the guide, gasket matched the ports and cleaned up the short turn radius. Don't recall the exact numbers but they made about a 30% improvement in the peak flow and made improvements across the lift range. As I recall none of the improvements had a significant change above .5" lift.