360 Tune Up

I am running hypereutectic pistons. Summit P/N SLP-8KH116CP30. I can't find the specs on them, however. (You wouldn't happen to know would you?) They must have changed them. This one pings hot or cold with low octane fuel, even with my new timing setup.

Maybe my water pump is not as efficient as yours. Also, I am running AC. I'm at the end of my rope chasing this and a $75 pulley is the easiest thing I could try. Remember, I am pushing an old car body with a lot of wind resistance. It sits high and doesn't flow well. In 5th, it's not turning many rpms and I'm stuck with my radiator or a similar design.