When you “tune” a car, what exactly is it changing?

Question

TIA

In: 639

Answer 1

It varies.

During the old times, pre-computer, a ‘Tune’ up consisted of replacing worn parts (points, plugs, belts, ignition wires, etc), tightening anything that was loose, adjusting the timing and gapping the sparkplugs. (Ensuring the gap the spark jumps across was optimized for the type of gas you’re using and your engine).

Some of those are still relevant (replacing belts, wires and gapping sparkplugs), but most Tune Ups are computer-based.

Now a ‘Tuned’ car usually refers to a car with many aftermarket replacement parts with the sold purpose of making it go faster.