tuners.wtf is +/- timing do ???

Well most n/a cars run best in the low 13 a/f range BUT not all(my car made more with a 12.6 ratio)
s/c usually want a safer number around 11.5-12.0

You should retard timing when-using nitrous,or supercharging or any forced induction application. Can be advanced when running n/a but not detonating

lean to a certain point is good(see above) but too lean is dangerous (anything 14.0 or higher)

General perf tune messes with timing and a/f ratio but also plays with other things to numerous to talk about

Red gave you a good baseline to go on. for blown cars 11:1 is a good safe area. the higher the ratio the more power you make, but the more of a chance of detonation.

same with timing... you can add degrees of timing to your tune, also known as spark advance. this will hit the plug sooner or later in the cylinders cycle. sooner being advancing, later being retarding. this plays a role in power and detonation as well. the more you advance the more power, however just like AF you also increase the risk of detonation.

unless you have a wideband AF gague then you really cant "dial in" your AF.. and timing it just playing with the numbers to get the most power possible without detonation. also understand that if you increase timing, lets say... in the winter... you will haev to pull it back a bit in the summer as hotter air with a high spark advance can cause detonation.

for NA i am currently at 14.5:1 (a little lean, and yes i do have a little detonation) but compensate with higher octane. when i get a tuner i will correct this down to around 13.5-14:1 and raise the timing a little (i know my detonation is due to the AFR.

more advance, and the leaner the tune the more power. but the more damage you can incur.

hope this has helped.

Torianlth