TF & Speedmaster Flow Tests

Yellow Duster said
What specific problems did you have with the CNC Speedmaster heads? I have a set I haven't used yet. They did get a going over and flow test by a local shop. Everything looked good.

I had these tests in my computer anyway, so it was easy to print out. This illustrates my concern over my set of CNC SM heads. Hopefully yours are better. There are 4 heads compared against one another on the intake side. A stock Trick Flow 190 CNC ported. A stock Edelbrock RPM (not ported). A Speedmaster factory CNC ported. A stock 1973 Mopar 587 iron casting. All heads have 2.02 valves except the 587 which has 1.88 valve. The CFM graph shows the SM heads to be pretty good, but the velocity and port energy graphs show a different story. I believe the lower velocity and lower port energy would lead to sluggish performance at low rpm.

This graph shows how bad my set of CNC SM's are. With a good valve job the curves should be up there with the TF. It's baffling to me because it takes just as much time to run a bad CNC program as it does a good one.