I guess I should have looked harder, I knew what a catalyst is from chem, but I have never seen a negative catalyst. So I grabbed my chem book and tried finding negative catalyst in it, I couldnÆt so assumed that I probably wasn't a true word. We always adjusted reaction speeds with temperature. I'm not sure what chemical could be used to slow down the decomposition during combustion.

I must stick to "gasoline does not explode" It really does burn. It burns from the spark plug out in a controlled fashion. It is only a couple of milli-seconds (about 3 on average) and it is effected by things like compression ratio, ambient temp, bore size.. ETC. The whole reason why we have timing advance is to give the gas enough time to burn and exert pressure before the exhaust valve opens.

I would never put it in my car, but if you feel it helps, why not... Acetone is cheap.