high speed miss

Hi guys, I recently got a 318 duster. You can see the car in the Welcome Wagon http://www.forabodiesonly.com/mopar/showthread.php?t=50051

I got the car from a guy who got it from a guy. He didn't know anything about the car, and I've yet to track down the PO before him. Anyways it has several problems, the first one I'd like to fix is a high speed miss.

The engine has a slight cam (340ish/RV type) I don't know the specs yet. Iron manifolds dual exhaust. Edlebrock Performer intake and a Holley 4160 vacuum secondary 600 cfm carb. (list# 80457-7)

when I first got it the vacuum advance was plugged off and the choke disconnected. Also the vacuum canister was pointing directly at the back of the intake so the vacuum line had a sharp bend to it to get it on. also the plugs had a good color but to the lighter side of tan, but the gap was .025 to .030 so I re-gapped them .035 to .040 also re-set the gap in the distributor between the reluctor and the pick up to around .008 to .010. (it was closer to .020 when I checked it) I also replaced the fuel filter and I'm using 92 octane gas.

Its got electronic Ignition w/ a chrome 5 prong ECU. The #3 prong/green wire is not being used. It also has a 4 prong ballast resistor but is only using one side of it, the 1.2 ohm side. votage measures 3.5 here and drops as rpm's increase. (dropped to 2.8 before I let off)

The car has a high speed miss at around 3 grand (I dont have a tach.) it starts right before the 1-2 shift w/ a stock feeling converter. once it shifts to second and the RPM's drop the miss goes away until the RPM's rise again then its sputtering badly and I have to back pedal on the fuel for it to shift to third. Then its running smooth again. till the RPM's come up.

you can floor it and it sputters instantly, you can stay on the gas and it never clears up. let off a little and its ok, but you cant go back up or it will start up again. The engine never dies as if its starved for fuel though.
also, I put a paper clip on the rod going to the secondaries diaphram and took her for a spin, and it never moved so they never opened. but it will miss reving it in park so the problem may be 2 fold. And I'm not sure the secondaries staying closed would cause a stumbling/missing motor.

sorry if this post seems like "War and Peace" I just thought I'd tell it all to speed up the trouble shooting part. I've been fooling w/ it for a couple days with no luck. To those that read all this ... Thanks!!!
Dietz