Intake Manifold Flow #'s

cracker said

I just got thru porting a victor manifold for a 440 and the 4 corners of the plenum were very shrouded and with the carb on the manifold all 4 barrels were at least 1/4 shrouded. I had already looked at the chevy BB victor and several others that were wide open with no shrouding at all. This manifold now has a nice blended entry with no shrouding and sure does look better to me.I'm not a flow bench but I'm not blind either. I have no idea why Edelbrock would make that manifold like that.

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Here is the bad news. We have dyno tested the Victor intake you just opened up and you just lost horsepower unless you use a spacer and rev the engine to 6,500-7000 rpm.

I don't know where the dyno sheets are right now but we tested the OOTB Victor, The Victor with the plenum blended to smooth the rough edges right underneath the carburetor without opening the "throat", and we opened the "throat" and blended them right into the intake runners. The best peak and average horsepower was with the throat rough edges smoothed and not opened up. It was a significant difference! The ported plenum Victor with the spacer never gained back the power in the lower rpm ranges it lost by opening the "throat" but it did get an increase by a few horsepower in the upper rpms over the smoothed "throat".

You haven't lost a great deal but the manifold was designed like that for a reason.