So I'm about to change the distributor on my 91 Suburban with the 5.7L TBI engine. I've also been wanting to put a hotter coil on along with quality cap, rotor, and wires. I would then gap the plugs wider and bump the timing earlier in an effort to get a little more power and ,more importantly, get more MPGs. I got to thinking about it, and I'm wondering if bumping the timing is actually going to have an effect because of the timing being at least partially controlled by the computer. Will the computer retard the timing to compensate for the advancing I did? Or, does the computer-controlled ignition just start from the base timing I set and advance only from there?