so, is tetraetheyl a different compound[additive] than tetraethyllead ? or are they one and the same ? was the "original" intent to find an exhaust valve lubricator/seat protector and a "side" benefit turned out to be an octane booster ?
Thats bass ackwards. It was an octane booster that turned out to be a valve seat lubricator/seat protector. Tetraethyl can not exist on its own, it exists in compounds with other elements, lead being one of them. When someone talks about lead in gas, they mean tetraethyl lead. And yes, its just Wikipedia, I did my research elsewhere.
Still not convinced? Try the wiki for TEL...
https://en.wikipedia.org/wiki/Tetraethyllead
