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Original 65 engine - lead substitute

Discussion in 'General Mustang Discussion' started by Gas_Pumps, May 20, 2018.

  1. Gas_Pumps

    Gas_Pumps New Member

    Should a lead substitute be used on an original 65 289 that has never been rebuilt and has the original heads? If so, how much and how often? Where can you get the stuff?
  2. Midlife

    Midlife Well-Known Member Staff Member Moderator

    No need unless you are going to use the car at sustained high revs. The problem with unleaded gas is that it can lead to recessed valves, but that is rarely seen unless one does sustained racing. [Note: even though someone here on the forum claims to race, it is never sustained enough to warrant the use of leaded gas.]

    The next time the engine needs an overhaul, hardened valves can be substituted for the originals.
  3. msell66

    msell66 Burning Fossil Fuels at c2 Donator

    Do you NEED to run leaded 110 race fuel...no. But it sure smells good!
    tarafied1 and Mach1Mark like this.
  4. Horseplay

    Horseplay I Don't Care. Do you?

    Just to avoid any confusion, it is not the valves themselves that would get replaced as much as the valve seats. Older heads should have new hardened seats installed when the heads are rebuilt. Most times the old valves can be reused.
  5. rbohm

    rbohm Active Member

    Op it really depends on how much you are driving this car. if it is just a weekend/back up daily driver, then you dont need to add anything to the fuel. if it is a daily driver, you dont need to add anything to the fuel. if it is an all out race machine, then you best be using the best fuel you can afford, AND you need to be going through the engine and freshening it up every couple of races.

    modern pump gas has lubricants added into the mix to prevent valve seat recession, even hardened seats can have that issue just not to the degree of older engines.

    in the end dont waste your money.
  6. tarafied1

    tarafied1 Well-Known Member

    yes it does! I love going to the track.

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