1. Does the timing affect your MPG?
2. I need a little performance should I move it towards advance or retard?

Thanks!

 

Yes, timing will affect MPG. If your timing is dead on top dead instead of whatever it should be like 6 degrees before, the idle will be different, possibly too high. Same with distributor timing, if you adjust the distributor, you will affect timing, but can do it a lot easier and in smaller increments, unless you have aftermarket cam gears.

 

You will not get the gains your hoping for by adjusting ignition timing.