A few quick questions about advancing the timing of relatively stock 86' GT, if I was to bump up my car's factory timing of 9-10 degrees to about 12 would I notice any difference in my car at all such as gas mileage or power/acceleration or would i need to do more to the car and advance it more to around 14 degrees or should I just leave it as it is?

 

I advanced my timing to 14 degrees and run 89 octane just to be safe and not only did the car idle and run better but it was definitely more "punchy" when I hit the gas. On a dyno I'm not sure how much hp you'd see but its at least a little. In my opinion if you only advance to 12 you can still run 87 octane easily, too high of octane without enough compression/spark will loose some power.

 

Well immediately after advancing timing to 12 degrees U put a little more than half a tank of 89 in the car and in ran fine, I got on the gas several times and it ran great but I haven't really put the car through its paces in a good while so i've pretty much forgotten what it felt like before the advance in timing