Ok guys, I have a 383 with 10.4:1 and trickflow aluminim heads running on 110 octane fuel for right now. It has a Mallory comp 9000 unilite distributor that has no vacuum advance on it. I also have the Hyfire 6AL box. My cam is the Comp Cam 294 Extreme 250/256 @ .050 and .519/.525 lift. I also have a victor jr intake topped off with a 750 demon carb. It also has a 700r4 with a 3800 stall converter and 3:73's. My problem is I just got the car running this past weekend. I have a digital timing light and my buddy set the light at 20 degrees and then had me hold the RPM's at 2000 while he turned the distibutor so that the balancer was reading 20 ATDC when the light flashed. Now I thought it should be flashing when the pointer was at TDC, am I right? The reason I ask is because the car won't idle under 1200 RPM and it idles violenty! It looks like it's going tear the motor mounts out of the car at idle. But it starts right up cold or warm and the throttle response is very crisp! I have tried adjusting the mixture screws to smoothen up the idle with no help. Now I know that the car will have a radical idle with this size cam but I don't think it shouldn't shake so much. And yes the entire rotating ***. was externally balanced. Any help? Was the timing set wrong? Am I overlooking something? Thank you!