Valve seats

[October-1881]

I don't know if this is the right place to ask, but could someone get me up to speed on hardening valve seats. I'm not an engine guy and I would like to know what exactly happens if the seats aren't hardened and non-leaded gas is used for a long period of time. I'm looking at a '66 Mustang with a 289 that has 80,000 stock miles on it and thinking about driving it + 2000 miles home.
Thanks

[Rick Parker]

Driving it 2000 miles will probably be OK, if the engine is in overall good condition. There are additives that can be added to replace the lead removed from the current fuel. When cylinder heads were made in the 60's the valve seats were integral, meaning they were ground on the existing cast iron without using any seat inserts. Current technology involves machining recesses and press fitting a cylindrical insert of an exotic alloy and grinding the correct mating angle for the valve. Then using a different valve material. Attempting to update current OEM heads by replacing seats and valves is probably more costly than purchasing current technology aftermarket heads.