[blykins]

Haven't had them on a running engine yet, but out of the box, they're pretty sweet.

I got a set for a personal project, and with a valve job, seat blend, and a pair of Pro Flo Manley valves, they were moving 308 cfm @ .600". That's with no porting whatsoever, just blending in the seats. Valve size was 2.08"/1.600". Very quiet and smooth on the bench.

They are available with CNC porting now, flow numbers are similar to Pond heads with a more conventional sized valve.