what do you do if you put jp8 in a car?

[Torch]

If you live in a town that has a race track it is fairly easy to get AV-GAS, everyone and their brother goes to the little airport to get 100 octane (low-lead) AV-Gas for their race cars, I used to put it in my 1968 Chevy Impala. It probably didn't make it run any better but the valves probably appreciated having the lead on them again.

But JP8, or even JP4? That might be harder to get unless you have a valid reason for buying it.

Whether it is AV-GAS or JP8 you don't want it in your car, JP8 will not burn correctly in gasoline powered piston driven engines, AV-GAS will burn in gas powered cars but the lead in it will plug up your catalytic converter. So, either way, dump the tank, blow out your fuel lines with compressed air then refill the tank. Should be ok after that.

Then go whack your friend over the head with a stick for doing something to your car without asking.