Thread: Unleaded in leaded engine

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I've been reading up on the unleaded fuel issues some of our older engines face. I guess the lead in the old gas engines coated the valves to help protect the exhaust valves from being burned. Soooo if we don't know the existing originality of our valves in our pre mid 70's engines, it is posible to be burning our valves using our only gas choice-unleaded!
I remember in High School our shop teacher talking about this, back in 1978. Some guys then were adding two head gasgets to their engines to avoid this.
Are any of you doing the same, or adding any additive to the gas for these problems! Will rebuilding the heads and changing out the valves fix this problem? Do the valve seats also have to be replaced. My engine seems fine right now, but good to know these things(mine's a 71).

There are additives available for this ,you could use every other tank or so.
If you are using this to do burn outs /cruise around etc ,its will last for quite a while .
Daily driver ,100 miles or more a day /drag strip after drag strip run ,will burn them out out pretty fast...20 to 40 thousand miles or less.
Considering 100,000 miles on a engine in 71 was doing pretty good I would not worry too much about the unleaded street fuel.
Now if you get new heads or have these redone in the future,I would get it fixed for the new fuel.
Basically if its installed and running ,I would run it as a toy or race ,untill it actually burnt the seat or valve ,then get it fixed,if you plan to tear it apart anyway ,it maybe a good time to address this,bottom line ,they wear faster than the new ones ,how fast is dependant on use.........

Thanks, that's my plan, if it ain't broke, don't fix it! Will only be used for the occasional cruise/weekend!

My brother has been running unleaded in his stock 39 Dodge for the last 7yrs w/o any problem & for 3-4 of them years he would put about 600 miles a week on the car...Joe

Good to know, Joe! Hey that ryhmes! I figure my engine has good compression and looks ancient so it'll survive for now! No pinging or knocking either. How about premium vs. regular. I heard uping the octane helps cure the problem!

My own personal opinion about premium vs. regular is this. I had a 84 Suburban w/a 350/700r4 in it & it pinged like crazy burning premium, so I went to 87 octane & by the time I ran 3-4 tanks through it the pinging stopped. Even pulling a 16ft fully loaded trailer I would use nothing but 87 octane. BUT I will say this not all fuels are made the same. Some I got almost no mileage out of them (6-8mpg) others I got 10-13mpg out of them. Not really a lot better BUT it beats 6mpg...Joe

only big thing that needs to be done is hardened seats.

What are some additives that you guys have used?

trick fuel i think bardahl makes one good as gold or lead o gold or something. have heard good things