Classic/Antique Car Repair: leaded additive, e type jaguars, valve seat recession

Question
Hi Howard,

I have a 1968 Mercedes 250SL. Should I be using a lead additive in the premium gasoline?

Thank you.

Answer
Hi Jeff,
I am not a Mercedes tech but lead was the oil company's method to raise the anti detonation level. (Octane rating) without further refining. The only benefit other than that was some lubrication to valve seats and valve faces. Many unleaded fuels have other lubricants. Lead was removed because of the pollution.
My background was MG, Triumph & Jaguars and most of those cars back then did not have hardened seats or valve faces and ran best on Amoco high test "White" gas (no lead)
I ran a lot of tests on Amoco "white" gas in E-Type Jaguars and found more power, fuel mileage and longer plug life and exhaust system life and no valve seat recession, than many of the leaded fuels available back then that boosted of higher octane ratings than Amoco.
I have not tested the new Amoco (BP) but have been using it in older Jags with no problems.
1968 was the start of emission control on many cars so first check to see if that Mercedes has a CAT. If so you can't use lead. I don't recommend lead in any fuel.

Howard