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As some of you may have read before, I am trying to work the bugs out of my 83 El Camino's engine. I have a late '86 Corvette 350 with aluminum cylinder heads with my factory computer feedback carburetor system installed. I am running stock 83 aluminum intake, a High Energy Comp Cam(p/n 12-210-2), and no emissions equipment(smog, EFE, EGR, Catalytic Convert). It has a tendency to stumble/misfire a bit on light acceleration(between 1,000 and 1,800 rpm), and stumble at higher RPMs (4,500-5,500) at wide open throttle. I am sure the higher rpm problem is the secondaries are opening to soon because I haven't adjusted them yet, but right now I am focusing on the low rpm stumble for everyday driving. I was wondering if the timing would be a problem because of the different cam setup and the stock computer chip. I was told by someone to go beyond doing basic ignition timing and do total ignition advance timing. I have read on how to do that with non-computer engines, setting total advance between 32 to 36 degrees of total advance. However, everything says to unplug the vacuum advance and plug the hose, set the base timing, then take it up to about 3,000 rpm and dial the timing in off of the mechanical advance. Can this be done to a computer controlled distributor? I can set the base timing no problem, but when I have done this in the past I had to play with the throttle to get the engine to stay running. I remember looking at the timing mark when I snapped the throttle and not seeing the timing move. There are no mechanical weights or springs under the rotor button, so it looks like all of the ignition advance is controlled by the computer. Since this appears to be the case, does it stand to reason that to adjust total ignition advance I should leave the distributor plugged in and rev the engine to 3,000 rpm to adjust the total advance? Also, if anyone has any other ideas about how to get rid of this low rpm stumble, I would appreciate it because the way my rear end is currently geared with my overdrive transmission, my truck runs at really low engine speeds to the point that I have to drive around town in 2nd gear to keep the engine speed above 1,800 just for smooth operation. I actually don't shift into 3rd until 55mph just to keep the engine speed above that point and I don't even use 4th anymore.