[Stan Weiss]

Originally Posted by 25stevem

I say flat out BS to the speedmaster listed exh flow number of 72 cfm@ .100” lift !!
If true then that 1.66” exh valve is flowing as much as the 2.11” intake valve, while having 25% less curtain area @ .100” lift.

It’s either produced by a mistake in the lift point used in the flow testing , or a back cut exh valve was used, or some of both.

Steve,
Not to say it is not BS.

But I have flow numbers from Edelbrock Performer RPM 60599 SF1020 Ram Air IV Exhaust Alum 2.11"/1.66" @ .100 71/69 which is 97.2% Exhaust/ Intake ratio.

I also have from someone for a SBC / L98 head 1.94"/1.50" @ .100 60/70 which is 116.7% Exhaust/ Intake ratio.

Stan