I'll do a back to back test early next year when I change my 512 low over to TF240 heads. Right now it has MCH ported Edelbrock heads on it. I'm sure the TF heads will pick up power based on the testing I did with my Coronet engine. I ran both heads on the Coronet engine and the TF heads worked a little better. A little more torque and a little more power. Nothing huge, but roughly 10 to 15 better at the peaks with everything else very close to the same.