timing or fuel first?

[IndyPaceCar]

of course if you're running rich, it'll want a bit more timing to burn all that fuel, as well as you'll have more tolerance to the added timing due to rich mixtures providing cooler combustion. so as you perfect your fueling, i usually notice that a bit less timing is required.

That should also cut down on all the popping in the exhaust (like a real race car LOL ) when I back of the throttle?

[steveo]

oh thats a combination of decel enleanment and timing. when you have very free flowing exhaust and a bigger cam, those very low MAP cells are critical, and decel enleanment too. in EE (which is mostly what i tune) decel enleanment can't even be controlled, so i just dick around with timing until it burns all that fuel off. funny that if you go too advanced, though, it actually starts making power during decel again and you dont get much engine braking at all.

[delcowizzid]

base timing should remain at 10 degrees if the engine cranks into life without windmilling while cranking.it only uses the base timing at crank and in diagnostic mode.base timing in diagnostic mode and referance angle in the tune must match to make the tables read real commanded advance.also the time demain correction setting is there to adjust timing LAG of the ignition module to keep timing correct as rpm rises .if you old tune was 16 base and 32 all in set the 100kpa colomn to 16 degrees at low rpm raising to 32.if you have longish runners or have knock at max torque you make the timing table dip at max torque then start feeding the advance back in as VE drops off not uncommon to run more advace down low then lower it round max torque then ramp back up to match the ve being low at low rpm highest at max torque then falling again.