The valve seats can be changed to more hardened ones. I just had a discussion with a machinist on having this done to a set of 66 Olds heads and he says to put the hardened seats on only the exhaust valves. His comment was that without the lead in the gas the valve pounds the seat when closing and will recess it over time.

I was surprised to hear that only the exhaust valves need it, but maybe some of our engine builder types on here can expound on this more. Conversely, the first machinist I contacted said hardened seats are only needed if you intend on driving the car a lot, as in being a daily driver. The second machinist scoffed at that.

Also, there are lead subsitutes you can dump in your gas to replace what is no longer there at the pump, but that would get old and expensive I would think.

Don