Hardened Valve Seats or Not?

Hi,

Back in the mid 70's when they started to reduce lead content and when it finally went away my 71 Charger 383 lost 3 exhaust valves after several 6 hour highway trips. Fortunately, B block engines were still in production in the late 70's and I was able to swap on a set of later heads with hardened seats.

The valve seats in these engines were only surface induction hardened and depended on the lead for lubrication and heat transfer from the valve surface. I have to agree with SGBARRACUDA it's only a matter of time before the valves burn. If it were mine I would do the hardened seats now. I had hardened seats installed on my 69 Barracuda 318 when the heads were redone.

By the way, I pretty sure that old time Amoco unleaded was loaded with phosphorus which did the same things as lead in terms of the valves.