When I advance my car around 15* - 18* and I come to a stop light or stop, the car begins to surge. Usually at a Stop the car idles around 650 -700 RPMS, steadily. But when I advance the timing, it starts jumping around like 500 to 800 RPMS, and since im on the brakes, it feels like the car wants to move forward, then suddenly it just turns off. Dont get me wrong, when I advance the timing and I floor the car, it feels very strong but the only thing that pisses me off is the part when it turns off at a Stop. Anyone else ever get the same problem? I do have an E-cam with 1.7 RR's, and I always use 93 octane on my car. Anyone have any idea what causes this, or is this just normal? Thanks.