ok, don't know if this is the right thing to do, but i'm going to start a new thread.

here is the ignition setup:

chrysler electronic ignition, set up by FBO with 12 degrees advance.
msd blaster 2 coil.

with this setup, the engine made 712 hp at 6k on the dyno. the dyno had a 6A MSD ignition box setup already in place.

put the engine in the car with the same distributor and coil, and my 6AL analog box. at first, the thing seemed awesome, but that may have been me getting used to it. but soon i noticed what seemed like issues with the old analog box, so i decided it was time to get a new one.

got a new 6AL digital, and the engine would run for about 30 seconds, fall on it's face and die. fought MSD, they finally agreed to RMA the box. sent it to them, got it back, and it did the same thing. i went through every test they asked for, and they sent me a new box.

- put the new box in, set the rev limiter at 6200, and it did NOT display the symptoms of the earlier box.
- the engine would not rev above 5000. 5000 was a hard limit, even with no load, would not go above 5000.
- set the rev limiter to 6300, and the 5000 limit was gone.
- now found that the engine was missing badly above 5k, and simply would not go beyond 5700 or so, missing the whole time.

what we did:

- tried a different distributor
- tried a different coil
- isolated the wires to the distributor from the MSD box
- isolated the hot to the MSD box
- checked the voltage of every wire connected to the MSD box

no change.

put in a dual point distributor and a napa replacement coil, NOT running through the MSD box, car ran like a raped ape, revving freely all through the range, NO issues whatsoever.

every action listed below exhibits the same problem:

- put the old distributor and napa coil back in connected to the MSD box.
- put an entire new wiring harness, using every single wire new, in other words, not a single wire that is currently on the car.
- put a brand new MSD blaster coil on
- put a brand new MSD 6AL box on

once i put the new MSD box on, i set the rev limiter at 6200:

- the engine stopped at 5200, even with no load.
- changed the rev limiter to 6300, and the engine stopped at 5800 with no load.
- changed the rev limiter to 6500, and the engine will go to 6200 with no load
- under load displayed exactly the same symptoms, missing and breaking up and will not go above 5700 or so.

next step:

- putting the points distributor back in, and will connect to the MSD box

step after that:

- find and alternative to MSD.

ok, so notice that both brand new MSD boxes, with the rev limiter initially set at 6200, would not allow the engine to go beyond 5000 the first time, and 5200 the second time, and that a mere 100 rpm change allowed the engine to go almost 1000 rpm higher.

so,

- what the hell is going on here?
- what do i do next?

and more importantly:

- what is the alternative ignition system to MSD?

This may be a total waste of time, but charge your battery fully and see how it runs..

Sounds like the one thing that hasn't been tried is another electronic distributor triggering the box, could be a problem with the Mopar pickup. Trigger the box with the points and see what it does. If that works its in the Mopar distributor (probably the pickup).

Lots of people have problems with the digital 6.
Seems to be very sensotive to rfi.

Once I rid myself of the MSD Digital 6 and put a Crane HI-7 in my junk, all the missing and crapping out vanished..

BTW, I changed everything too, and MSD was at the track, (national event) and checked the box out twice.. Said it was good..

Bought new plug wires right there, and a new distributor..

Well, at least I have spares..


Chris..

Buy a ICE ignition and be done with It. You will be happy you did.

I had same issues with a digital 6. Ice has a new box that's compatable with other brand name components for $299 and it is a 7amp box. seems to improved my 60'.

Bet it runs great with the points and MSD.
I am diagnosing your problem as EMI (RFI). You haven't mentioned your plug wires. Something is causing the probably more sensitive digital circuits to "see" more trigger events. That is probably interference from the ignition leads finding an unshielded area on the trigger circuit.

I have an electronic device to monitor my heart. Strong fields can be picked up by the leads from device to heart, fooling the device. Same for your system.

R.

this is the rotor that has been in the distributor since new. it has about 1500 miles on it. there is no evidence of spark scatter in the distributor, and i even used a cap that has fire rings, with no change.

but this does look worrisome, all the coloring below the tang.

could this be an issue?

oh, and the guy from MSD just told me that i CANNOT run the blaster coil horizontally. it must be run vertically, or there isn't enough oil to cover the windings, and it will heat up and break down.

from the coil instructions from MSD:

It is recommended to mount the PN 8202 and 8223 coils in an upright position. The High Vibration Coil, PN 8222, can be mounted in any position due to its epoxy potting compound.

Not sure if I missed it but what wires are on it? I agree with the RFI ideas and wires are a big source of it.

Well, onto the other leading idea, its got to be some kind of interference. You're using resistor plugs correct?

I'd borrow a known good old style analog 6AL box and try it.
I don't know what to tell you to try w/ the digital box b/c I tried everything I knew of and never got it to clear up.
I think maybe your old 6AL crapped out and the new digital box is just having a fit for some reason.

There's a guy in North Carolina that repairs MSD products...Pat Collins at TechWest Racing. 704-995-4286 He's repaired boxes for me in the past and has done a great job.

I've also ran the Blaster 2 coils horizontally for years and never had a problem.