ignition stumble at 2200rpm

[bigblock502]

Well I'm back with another question sooner than I thought I'd be. I got the car to idle smoothly. I used Cygnusx1's maps (the first set of maps listed before EDIS)to start with because his setup was similar to mine. The car will idle all day long and runs smoothly above about 2300rpm. Between about 2200-2300rpm it stumbles quite badly. The timing light shows misfires on all wires including the coil wire while the car is stumbling at this range. I tried using fixed timing just to see if that changed anything but it had no effect. All my maps match those of Cygnusx1's post exactly and none of the numbers look out of place to me. I fouled a set of plugs while first getting the car to run but have since replaced them after I got the injectors and required fuel set to the right parameters. I'm puzzled as to why this small rpm range is the only affected range. Any input will be appreciated. thanks

[Matt Cramer]

Exactly what sort of ignition do you have?

[vantage]

With a distributor setup this is a classic indicator to a worn axle which starts to vibrate at a specific rotational speed. With an MJ/MS setup this might be vibrations in the sensor setup, either the trigger wheel or the sensor mount starts to vibrate at 2200 RPM. If you have a scope you might want to have a closer look at the sensor output waveform and timing while running the engine through the problematic RPM range.

[bigblock502]

I'm using the stock 83 turbo distributor and driving the coil directly with msII.