Stock Ignition Limitations?

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73Swinger18

73Swinger18

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I have a '73 Dart Swinger w/318 and have the following aftermarket OEM style ignition components installed...

Control: Ignition Control Module

Coil: Ignition Coil

Distributor: https://www.napaonline.com/en/p/NRD483890

I've been troubleshooting a stumble at WOT above 4,500 RPM and would like something that will handle 5,500 RPM. I've gone through everything else and now am going to try to upgrade the ignition. I'm thinking about ordering an orange Mopar control. I'd like to try one component at a time to save some cash, so not sure if the control or coil would be the first thing to go after. Any coil suggestions? Thanks!
 
Fact: I have spun many small blocks to 5500 rpm's off of the factory stock ignition systems.
 
The Mopar orange box's are junk. They might have been good back in the day, but I've had issues with all the ones I've tried lately. I had decent luck with a Mopar chrome box. The blue one is for racing if I'm not mistaken.

The Mopar electronic ignition is a good set up, it's just getting good components. FBO makes good stuff that works with the stock system.
 
Just find a Standard Ignition LX101 box NOS on Ebay. Problem solved. We also sell the Borg Warner Select Ignition boxes at O'Reilly.
 
Shoot, I used a single point dizzy with an accel coil in a Duster and turned 6k all the time with a 340 cam and headers. It ran a best of 13.50's with no traction whatsoever and a stock 727 torque converter (not the high stall 340 converter either.. lol).
Naw, if your staying 6k or under, no need to be thinking the factory ignition won't handle the job....
 
whitepunkonnitro said:
A dead stock single point with the cheapest points you can possibly buy, triggering the mildest stock coil ever offered on any 12 volt Mopar will get you a clean 5500+
You have other issues
Click to expand...
LOL.... we posted at the same time "with the same thought".... :D
 

318willrun said:
Shoot, I used a single point dizzy with an accel coil in a Duster and turned 6k all the time with a 340 cam and headers. It ran a best of 13.50's with no traction whatsoever and a stock 727 torque converter (not the high stall 340 converter either.. lol).
Naw, if your staying 6k or under, no need to be thinking the factory ignition won't handle the job....
Click to expand...

And they will work great. They did a LONG time before fancy electronic stuff came out.
 
I'm going to do a leak down test on the engine. Maybe an exhaust valve is shot. I originally thought it was just a rich stumble when the vac secondaries opened up because it went away when I wired it closed. I tried every jet/spring combination yesterday with no joy. Wired the secondaries shut again and the stumble is now there even with them closed.
 
73Swinger18 said:
I'm going to do a leak down test on the engine. Maybe an exhaust valve is shot. I originally thought it was just a rich stumble when the vac secondaries opened up because it went away when I wired it closed. I tried every jet/spring combination yesterday with no joy. Wired the secondaries shut again and the stumble is now there even with them closed.
Click to expand...
An exhaust valve would be most notable at low RPM and would give a stead miss, not a stumble.
If your problem is more throttle load than position, focus on the electronics...but the simple stuff. Continuity test the wires, especially the coil. Scrutinize the cap and rotor.
 
Check the ballast too, if you're not getting the right voltage to the coil it'll cause you issues.
 
Could a faulty charging system cause this? I noticed my ammeter was dipped below the halfway mark and almost all the way to the left when I turned on the brights/AC. This was all after 20 miles of driving. I am normally right in the middle.
 
If the coil isn't getting the voltage it needs, it's certainly possible. It wouldn't be my first bet, but if the ammeter jumps all the way to the left when you turn on the brights you definitely have an electrical or charging issue. If the ammeter is pegging the left stop I'd be thinking more like a ground fault though. If it's just dropping left of center that could be a charging issue.
 
72bluNblu said:
If the coil isn't getting the voltage it needs, it's certainly possible. It wouldn't be my first bet, but if the ammeter jumps all the way to the left when you turn on the brights you definitely have an electrical or charging issue. If the ammeter is pegging the left stop I'd be thinking more like a ground fault though. If it's just dropping left of center that could be a charging issue.
Click to expand...
It's not all the way to the left, but it gets close. I'm going to get my battery tested. It did sit for three weeks waiting on the return of my carb from repair. Maybe that's why it got drastically worse since the last time I drove it. I was cranking the hell out of the engine yesterday with all the jet adjustments I made to fill the bowls back up.
 
Not that having the battery tested is a bad idea, but if it's having issues when it's running it's the alternator. 3 weeks of sitting shouldn't be an issue for the battery unless you've got an electrical draw, but if you did 3 weeks would kill the battery dead. More than likely it's the alternator that's bad and the battery isn't being re-charged. If the ammeter isn't pegging the stop then it's not a ground fault in that circuit, so, it's more than likely just the alternator not being able to keep up with the demand. So, have the battery and the alternator tested.
 
Got the battery tested. It was good, just a little low on voltage which was expected with all the cranking. Probably didn't drive enough to fully charge it. It's on the charger in the garage now. I'll get the alternator checked after I repair my fuel sending unit. I'm waiting on a new float that got filled with gas. Didn't feel like removing it when I could drive it in later. Below are some pictures of my rotor and cap. Is the burned looking area on the rotor normal or caused by not contacting the cap correctly? I didn't see anything wrong with the cap, only some slight discoloration on the points.
IMG_20170307_161840.jpg

IMG_20170307_161902.jpg
 
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The carbon around the rotor contact is a sign of high resistance. Your symptoms go along with that.
Just for ***** and giggles, do two things
First, swap out your coil wire.
Then, jump out your ballast resistor.
Take the car for a ride, and see if the problem clears up.
If it does, unjump the resistor, and see how it runs.
That'll tell you where to go next.
 
whitepunkonnitro said:
The carbon around the rotor contact is a sign of high resistance. Your symptoms go along with that.
Just for ***** and giggles, do two things
First, swap out your coil wire.
Then, jump out your ballast resistor.
Take the car for a ride, and see if the problem clears up.
If it does, unjump the resistor, and see how it runs.
That'll tell you where to go next.
Click to expand...
I recently moved my coil to the fender as shown below. This cured the miss I had at idle when heat soaked with the coil mounted on the intake manifold. Is this too far away from the distributor now? I'll try a new coil wire, but where do I connect the jumper on the ballast? I will have to wait until I get the float in the mail for my fuel sending unit before I can do any test runs. Thanks for the help.
IMG_20170307_173432.jpg
 
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