Older car - Newer gas.

[85_600]

I've searched on this subject and I'm just as confused about it as before.

Is there ANY truth to using unleaded gas in an older muscle type of car and the valve seats going South at some point? I've seen BOTH sides, Yes and No, out on the web. It's almost a 50/50 split on whether to use hardened seats or not.

Thanks!
Paul

[1FastCSX289]

I've searched on this subject and I'm just as confused about it as before.

Is there ANY truth to using unleaded gas in an older muscle type of car and the valve seats going South at some point? I've seen BOTH sides, Yes and No, out on the web. It's almost a 50/50 split on whether to use hardened seats or not.

Thanks!
Paul

The lead was used as a lubricant and the valvetrains were designed with this in mind. I have a 69 GTO and I used hardened seats when I built the motor 12 years ago. Still running strong on 93 unleaded. If youve got it apart, I dont see any down side to changing the seats (except $$$). But, its cheap insurance.

How old is the car?

[86Shelby]

From what I've seen if the engine is going to be run hard then yes, hardened seats are worthwhile. If it's just going to be a regular DD(no performance build) or a show car put the money into something else. Chances are since the car is old enough to have non-hardened seats it likely won't still be on the road in a DD situation many many miles down the road where the wear may become prevalent.

[85_600]

How old is the car?

I don't have one yet. I'm just doing some research for a purchase next year. BUT, it will be between 1967 and 1971, MAYBE '72 and/or '73, but most likely the first range.

P

[turbovanman²]

Hard to say when they switched over but 60's and early 70's won't have hardened seats. If your just doing the weekend warrior thing, just leave it alone and run an additive to prevent it. If your daily driving it, then I would yank the heads and have it done.

[Birddog]

Not an issue on small block mopars post 70. They were smart:eyebrows: ... Induction hardened seats.
Like turbovanman said it shouldn't be an issue if ya don't plan on driving it daily....