The Ford Barn

Mulletwagon · 05-08-2020, 07:52 PM

Thanks for all the responses. Much good info but never really did get the answer to the question regarding rebuild of engines up to the late 70s. If rebuilding say a 1965 289 that was all original, should the heads be rebuilt with hardened valve seats and stainless valves ? Does current gas have additives that make such mods unecessary ? As it was explained back in the 70s, the lack of lead allowed "microscopic" spot welds between the valves and the seats which caused the valve/seat erosion. Would agree the lack of lead in current gas does not effect Model A mills, and maybe no flatheads for that matter.

05-08-2020, 07:52 PM	#21
Mulletwagon Senior Member Join Date: Jan 2019 Location: Florida Panhandle Posts: 626	Re: Unleaded Gas Thanks for all the responses. Much good info but never really did get the answer to the question regarding rebuild of engines up to the late 70s. If rebuilding say a 1965 289 that was all original, should the heads be rebuilt with hardened valve seats and stainless valves ? Does current gas have additives that make such mods unecessary ? As it was explained back in the 70s, the lack of lead allowed "microscopic" spot welds between the valves and the seats which caused the valve/seat erosion. Would agree the lack of lead in current gas does not effect Model A mills, and maybe no flatheads for that matter.