Hey guys i just bought a 67 coupe that obviously only takes leaded and i was wondering if i should add additives or get the valves hardened.

how much would the valve hardening cost?would a typical mechanic be able to do it?

~thanks

 

it's not the valves that need hardening, rather the valve seats.
but the common sense on this forum seems to be that you'll only need to do that if your are towing with the car..
And I drove mine for 2 years without additives no problem. have new heads now so can't tell what the other seats looked like ...
as far as I know none of the lads here in the club use additives on stock heads ...
wonder what the others have to say

 

I drove my 68 for 9 years on the factory 370,000 mile 6er never had a problem. my dad has a 66 gto that he has had since new with 60,000 miles on it and its just fine as well.

 

It does not obviously need to run leaded fuel. Many older heads have been upgraded over the years. As Kalli said, it is not the valves that need to be upgraded, but rather hardened valve seats. The lead helped cushion the blow the valves gave to the seats. Without this, when the valves and combustion temp get really hot, they can hurt the seats causing the valve to not seal the combustion chamber well. Lead in the fuel also aided in minimizing detonation from high compression motors of the 60s. Without that, you simply need to run higher octane gas and set the engine ignition timing so that it does not ping.

If you pull your heads, I would replace the valves and valve seats, but if you car is running well, I would not worry too much. You can buy a non-lead fuel additive from most auto parts stores if it makes you feel better. Pulling the heads, machining the valve seats down, putting new seat inserts in, and replacing the valves is not going to be cheap. Most guys just opt for performance heads unless they are showing the car in concourse of something.