Av gas / Lead
The short answer is yes, you will end up with some lead on the powervalve, exhaust port, etc. As you're aware, some unburned gas will exit the exhaust before the piston closes off the port, this is where the lead comes from . I wouldn't lose any sleep over this, normal p.v. cleaning, using cleaning solvents, wearing some nitrile throw away rubber gloves should take care of any build up - lead, carbon, whatever. In the 1960's when muscle cars ruled everything, pump gasoline ran about 98 octane, to get this a refiner would use about 4 grams of T.E.L. -Tetra Ethyl Lead per gallon , it was readily available and it worked great with the naptha base material of gasoline. It also worked even better when other octane enhancers were added. Then the down - side , it was found to cause cancer,( pure T.E.L. 100% , not diluted in a gallon of gas) and the lead did cause pollution. The last year of leaded pump gas, the amount of lead was down to .1 or .2 grams per gallon. I don't know how much lead is currently used in AV gas, I would venture a guess that it is much less, but that is only a guess.
