If you have already run "Leaded" fuel for a good period of time it should have already deposited lead onto the valves & seats. As long as you don't do any hauling or high speed engine operation you should be OK. If you ever take the head off for a "valve grind" the lead deposits will be removed from the seats which could lead to early wear. In that case I would have replaceable seats installed for the exhaust (not needed on the intake). A few months ago I did some engine work for a guy restoring an early Ford Falcon with the 170 6 cyl. The engine had been apart before and had a "valve grind" done. It had run less than 10k since the rebuild but the exhaust valves were already "eroded" down below the surface of the combustion chamber!! Installed replaceable seats to bring the seat back to the proper level. There are very few engines that have problems with the intake valves. But the 360-390 Ford is one of them. Since most of these engines were installed in trucks they saw some heavy use. Not uncommon to see BOTH the intake and exhaust valves sunk so far in the head they are bottoming out the lifter and being held off the seat!! But HEY,,, that's just ME!! Bruce Hevner _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com