[Johnny Mullet]

I set my timing at 8 degrees advance for the best fuel economy on my 1998 Metro and set the timing on my 1995 Chevy 4X4 to 5 degrees advance.

Best way to find the "sweet spot" is to mark your timing where it is now. Advance it slightly and test drive. Under accel or load, if you hear ping or valve clatter, retard slightly until you get no more ping. Do this in small, gradual steps.