MSD Pro Billet ignition- are these unusually "voltage sensitive?" Got stranded, looking for ideas

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MRGTX

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The Dart stranded me last night for the first time since 1999 or so when I had a ballast resistor go bad and didn't know enough to have a spare one in the glovebox.

My best guess is that this is once again related to the ignition but for very different reasons...I am sure I'll be able to figure this out but thanks to my work schedule and family demands, I won't be able to touch it until Sunday and it's killing me...so I'm just throwing this out there for your input or opinions on where to start.

The car started up and ran normally, shortly after it reached operating temp, I switched on the electric fans manually (as I always do). A few miles later, while cruising at about 45mph (2200 RPM or so), the car started stumbling, then just quit. It started back up and ran rough for about 30 seconds, quit again.

Some details on the engine that may or may not be relevant - The engine is a BPE crate engine 408 stroker. Holley 750 carb, MSD Pro Billet (clone) ignition, nearly brand new coil (the exact one suggested by BPE), plugs, wires, fuel pump, etc as the crate motor has about 700 miles on it. The car appears to be getting fuel based on the gas in the fuel bowls and the normal squirt when moving the throttle...though I can't entirely rule that out technically since I couldn't see what it was doing while it was running since it wouldn't run long enough to watch.

The reason that I'm suspecting the ignition system is that the only anomaly that I noticed is that the battery was reading low on static voltage on the gauge. Unfortunately, the car started normally so I didn't think to look until after the problems started. Once I thought to check that, the gauge was showing ~11v with ignition in run position and no load on the system, ~13v when it was running (before stalling). I don't know for sure that the cheap Bosch voltage gauge is exactly accurate but it usually reads higher than this.

Last year (before the engine swap) I installed a new Optima battery along with a battery relocation kit running 0 gauge cables- it never seemed to be a problem but it could be relevant since it obviously introduces extra resistance to the system. I am running a 100A alternator (about 3000 miles on it max) which I haven't tested but until now, had no reason to suspect.

Thoughts are welcome.
 
If you don't have a battery meter, does the car crank over? If you have enough voltage to start the engine you have enough to run the ignition. I'd address the battery first.

Check for spark, if no then it's ignition. If yes, then you have a fuel issue.

This will be a narrow it down type of deal.

Who's clone ignition is it?
 
A ballast resistor is bypassed during cranking so and then current flows through it in the run position. Not sure with the MSD if it is part of the circuit but when it is, the car will crank and fire. As soon as you let off the starter and the ignition switch goes to run position, if it is an open ballast resistor, the car will quit instantly. Does not sound like a ballast if it ran for 30 seconds.
 
I had a Optima red battery fail on me.....going down a hill!! Engine just died. No brakes or steering. Yikes! When I got it stopped, I measured the voltage & it was about 6-8; left it for a few hours & the voltage recovered but not fully. I believe an internal short in the battery. Under warranty still, Optima would not replace it. Had to sue the bastards to get the money. Preparing for this, I found lots of examples on the net of failed Op batteries.
Try a new battery first, you might have a different problem.
 
Well, I think I may have found the problem. My uncle (who has been wrenching on muscle cars since before I was born) insisted that we check out the fuel system first. Within a few minutes, a huge problem showed up.

The metal inline fuel filter that I bought from Summit last winter was rattling around when I removed it from the line. The filter element was detached and the adhesive was breaking apart, sending debris into the fuel pump and carb.

I’ll get some pics up tomorrow but it’s a mess.
 
As mentioned, the filter element was rattling loose in the metal canister allowing anything and everything to get past.

This waxy adhesive(?) appears to be the culprit. Some of the cracking in this material is from opening it up to look at the pleats (which had some debris).

Emptying the gas from the filter into a cup showed quite a bit of debris swirling around.

A small amount of silty brown material was in the bottom of the bowls.

I filled a jug with gasoline straight out of the fuel line (pre filter) which came out perfectly clean.

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Just pulled the fuel pump, the fuel that came out of the pump has more crud in it. I’m trying to figure out if it’s possible to flush this thing out.

The pic is zoomed in pretty far. The particles are tiny.

The particles are apparently not from that deteriorating seal. They stick to a magnet. So presumably, it is coming out of the tank and the dislodged filter element just let it through.

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that's annoying about the fuel filter, but i don't think it'd kill the motor unless it hung the needle open and flooded the motor. that would be pretty obvious unless you took your time poking around, then the fuel would've drained into the motor.

everytime my needles have flooded my motor, it ran really rough at idle and would somewhat clean up at part throttle, could use the throttle to keep the motor running...it didn't just die all the sudden with no warning.
 
how old is the tank ? hope you find the problem quickly . good luck
 
Still sounds to me like a battery/wiring related to battery problem. I have seen a number of times an MSD type ignition act wierd or not even start the car with low juice.
Low voltage kills MSD stuff
 
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