Originally Posted by Miniracer23

Tune with sound and smoke. If the engine is running good and producing good smoke(this will vary depending on what fuel you run), than leave it alone. Really, the only reason to have a temp gun is for break-in and just to reference after a run.

I was always a needle turner and had horrible experiences w/ my engines. Once I stopped turning needles to get the temp I wanted, I had better luck.