Car lines run from garage-grade technical to pure innuendo, and the trick is knowing which the listener drives, so to speak. Horsepower and engine jokes suit people who actually care about cars; the smoother ones about taking a drive work on anyone.
Car shows, meets and long queues for parking are the obvious venues. In an actual traffic stop, say nothing — history is not on your side.
Car meets, shows and cruise nights are the home venue — the machinery is present, the crowd self-selected for exactly this humour. The technical lines are a handshake there: joking about torque to someone polishing a cam cover tells them you speak the language. Outside those venues, stick to the metaphorical ones about drives and destinations, which need no engine in sight.
If their garage runs to two wheels instead, the motorcycle lines cover that crowd — same horsepower jokes, more leather.
