[george kujanski]

Nope, Trev, I think Matt is correct. The Tetraethel lead additive was used to raise octane ratings, especially since the in the late 50's and early sixties compression ratios were going up; raising the CR raises the torque output, everything else being equal. raising the CR, tho, raises the tendency to ping, the TEL additive raises the octane rating to reduce that.

The valve lube, I believe was a side benefit; once the TEL went away, the mfrs started hardening the exhaust seats to compensate.

Raisng the CR is a great way to get more torque output, unfortunately, we're limited by the gas we can buy.

Diesels have more output torque everything else being equal, because they run CR, of, say, 18 or 20 to 1. Diesel also has a higher energy content, a win-win situation.

George