HAIRPINA slow, 180-turn, which exits in the opposite direction a driver enters.
HAMMER DOWNThe driver has the pedal to the metal or has "dropped the hammer" full throttle.
HEADERSA fine-tuned exhaust system on NHRA cars that routes exhaust from the engine; replacing conventional exhaust manifolds.
HEADSOCKA fire resistant head mask or balaclava.
HELICOPTER TAPEUsed to cover and protect exposed areas from flying debris, as helicopter technicians developed it to protect rotors.