Cylinder head dyno shoot out

I have tested with Vic 340 and with Super Vic. I have tested at 28" and 33". I have tested inner ports and outer ports because of pushrod location and swirl directions. Sometimes the dip comes out completely, sometimes it does not. But it always improves.

The TF head is the worst for flow back up. Part of that is because of the anti-swirl design of the port and part of it is because water under the short side limits the porting options. The anti-swirl features help the mid lift flow numbers, but when the flow jumps the valve the ported crashes hard. The TF needs the pushrod pinch opened up to make power, in my opinion. Opening the PRP makes the flow separation/crash worse. One of the 'tricks' to making a head flow well on the bench is to use the size of the PRP to limit flow separation and jack the flow numbers up. Works for flow numbers, hurts power.

I have not done it, but if I flowed the assembly at 10" there would probably be no dip. At 28" there may be a slight dip. At 33" the dip may or may not be more pronounced. I've been thinking about the correlation between high lift, high test depression flow and a head's ability to carry HP beyond peak TQ. On the flow bench, if we try to put a head in a high lift, high flow condition and try to create flow separation, can we SOMEWHAT predict performance of the head in a past-peak-torque high rpm 'choked' condition?