[Flygirl]

Thank you!

Regarding the plugs in the proper heat range, that primarily has an effect on fouling (too cold) or preignition (too hot)...right?

The only thing I know to look for on the plugs themselves is for is a nice light to medium brownish color (not black and sooty), and no evidence of physical damage. And driving the car, no preignition (difficult to hear on these cars, they're so loud) or signs of loading up during lower speed operation.

Is there a better, more scientific way to narrow down the heat range?

What would I see, if anything, on the plugs if max advance or the timing curve is improperly set? Would there be physical damage that was apparent...? Or is it more of a color shift?

I still can't quite understand the relationship between the heat range of the plugs and ignition timing. Or are they not closely related?