ProComp/Speedmaster aluminum heads

Actually they're the same size which they do call an overdrive. The regular crank pulley is smaller. I do have a much smaller March performance crank pulley that I used when I had my electric water pump on because that factory pulley would run the alternator too fast and fly off.. but the factory stuff in the picture the crank was maybe a half inch smaller than the water pump so I will actually gain a little bit...
Cvf racing...

The picture is throwing me off. The WP pulley looked smaller to me. Damn glasses.

I have the CVF Pulleys but somehow they dug around and found a WP pulley that is 6% overdriven and that’s what I bought.

I want to get something in the 12-15% overdriven size if I can.