[trebb]

How would this, if at all, affect power? No power difference, I would have no problem using it. If there is a power difference however, I wouldn't want to use it.

I used some on a fairly hot car in the 60s and got a perceptible power bump. I never checked it out as a way to improve mileage, but it seems like it might work oK if it isn't harmful to anything else.

[billbears]

Well thanks for the answers. No considerable power loss and I'll give it a shot. My truck gets 13 mpg and my Mustang gets 9-10 so any increase at all is worth it to me.