[justa6]

I don't think the two chemicals contain lead or manganese. Toulene is what is put into racing gas to raise the octane. Xylene actually increases it slightly more.

I know a lot of people who use the recipe and no one that I know of has had any trouble. It simply works. The aftermarket "stuff" uses pretty much the same thing except the ratio is too small to do much. 1/2 of an octane won't do much.

As for the Buick 6 I run, it is "Mean". 473HP 10.8@124mph in the 1/4 mile. No nitrous or turbo, just a 4 barrel Holley. Oh and it gets over 20mpg on the highway...

Regards,