tipping the can

introducing small percentages of nitromethane into the fuel tank of a methanol burning race engine to increase its power output. this practice is against the rules of most sanctioning organizations in most racing classes. the exception being top fuel drag racing. in top fuel and top fuel funnycar nitromethane is used in very high percentages with only small amounts of methanol. nitromethane (ch3no2) mixes well with methanol but will not mix with gasoline unless a small percentage of acetone is added to the mix.

driver; "if I cant cut a light we will probably lose the next round because we have to race the number one qualifier".
crew cheif; "lets try tipping the can and hope no one can smell the nitro".
driver; "that is a stupid idea. I like racing here". or "good idea! did we bring any nitro?"

peppered the plugs

when there has been to much nitrous oxide used in a motor leading to small black dots (tiny pieces of melted piston) resembling pepper on the spark plugs.

Fred; "I peppered the plugs"
Bob; better back off the nitrous before you hole a piston

pepper the plugs

a common condition in racing engines when there has been to much nitrous oxide, not enough enrichment fuel, to much ignition timing, to much boost, or any other tuning error resulting in small black dots (tiny pieces of melted piston) resembling pepper on the spark plugs.

driver; "did we pepper the plugs?"
crew chief; "yea, better back off the nitrous before we hole a piston"