How much can the heads be milled safely

With a smaller cam (cc502). How much can be milled from the heads safely without any valve to piston problems?

As little as possible! You should not be milling the heads for the purpose of reducing the CC size - ONLY to keep the head faces perfectly smooth. .005" is common.

What are you trying to accomplish, exactly?

I've gone .020 without any problems. I think I've heard .030 to be the limit before you'll require intake mating problems.

You will run into intake fitment problems LONG before you run into PTV problems.

You can mill .020" and then use a thinner Victor Reinz 5898 head gasket on the stock short block and "usually" still have the intake fit with no problem. If anything you might have to use a dremel and slot the intake bolt holes inward to keep intake bolts from digging into the inside of bolt hole on intake manifold.

Lloyd

Thanks for the replies.