[dogbreath077]

A knock or ping sounds like little ping pong balls bouncing around in your engine. If you hear that, it is either pre-ignition, or your spark plugs have come apart because no one has told you that advancing the timing will elevate the combustion temperature to a point that exceeds the design limitations of the spark plugs, and the valves. SO I SAY DONOT, DONOT ADVANCE THE TIMING, not on a plane, or in a house, or with a mouse, not ever, ever, ever. the spark timing is not a game for an ameture to play. I spelled that wrong, oops, but you get the point. I'd say if you want better performance, go with a performance exhasut, and air filter. cheap, safe, and you can feel the differrence.