weird issues with tach signal using wheel decoder....

[pitobread]

The setup is a 4age 20v silvertop running on MS v.3, we are using 2 extra vb921's to drive a ford escort coilpack directly(same pack used on edis)
We are using wheel decoder, cutting 2 teeth 180 from each other on the distributor. we are having 2 issues with it, one being trying to get our tach signal clean enough that we don't loose spark on one side of our coil and the other being we keep popping fuses to the coil(supposed to be 15, I put a 20a in therecause it was all we had) and last night fried a vb921(it got red hot and let the magic smoke out.)

The tach signal issue is what bothers me the most, the distributor is gutted, with the exception of the one pickup for the 24-2 wheel and is set as close as we can possibly get it. we currently arent using shielded wire, but are planning on getting some today to see if that makes our lives any easier.. when we crank we dont get a decent signal untill about 1000 rpm, IF we do, then our high rpm suffers.. so it's like a toss up trying to get it so we can get cranking rpm and not drop sparks and getting our high rpm set aswell.. we setup a test bed with a drill and got it ok, but it wasn't perfect.. we tryed following your settings for adjusting the pots, but we don't seem to get it right and we are usually waaaaaay off from there when we get a signal on the tach.

The other issues is burning up fuses, and vb's.. can we actually drive the ford coilpacks with the vb's the way we have it setup? becasue it was sparking at one point.. but now that we had a ok signal on the tach everything has gone haywire and we were popping fuses left and right..

Also what should we have our dwell settings at for this coilpack, anyone know?

Anyone with a little insight would be greatly apprecialted..