Well, if our heads are just 5 cfm better, then "they" don't have the best F.A.S.T. heads on the planet.

Here is a known factor. OOTB Edelbrock RPM head flows from our bench.

.100"......71-73 cfm
.200".....148-155 cfm
.300".....205-209 cfm
.400".....252-254 cfm
.500".....275-276 cfm
.600".....286-287 cfm
.700".....287-291 cfm

We had the 906 heads below on Comp Cams dyno when they forgot to turn the water on to the 500ci, 11.9:1, pump gas engine. They didn't catch the water problem until the exhaust valves seized to guides and pulled them out of the heads and the paint on the heads was starting to burn.

.100"......91 cfm
.200".....165 cfm
.300".....219 cfm
.400".....272 cfm
.500".....299 cfm
.600".....325 cfm
.700".....335 cfm

I was afraid the heads would have cracked but they didn't. We rebuilt the scrap parts in a few hours and with as much as 56% leakdown we made 12 pulls over 700 HP with 730 HP being the best. How many cfm should it take to make 730 HP with a good engine? During testing the heads made 694 HP on a 9.5:1 compression 451.

Like I've said before, I never figured to build these heads for anyone else. It takes about 120 hours of work.

What is 30 cfm worth if no one else can do it?