Need help tuning Quickfuel carb
What does the magnum motor have that a LA doesn't? Cheaper Mopar wires sold at the time of the install? I have been building motors and tuning them for a very very long time. Never did I see wires act different because they knew they were on a certain style motor.
Higher voltage coils cause wires to fail. If you can't afford good wires stay with a factory coil. All motors have non-conductive wire looms to stop them from rubbing through and allow the use of cheap wires. It is kind of hard to keep them from crossing paths at the distibutor with a firing order of 18436572. The same on all mopar V-8's. LA's and Magnums. The TSB for the misfire problem was for the wires running to the distributor stuffed under the firewall of the Rams. They had a hotter coil and cheap wires . When wet the wires would cross feed if to close. Been there.
I have a factory JTEC that's been reflashed running my Magnum. The reason I mentioned the issue with the spark plug wire routing is that when I first got the motor running, my Matco Scanner was showing the computer detecting hundreds of misfires. Everything was brand new from rotor to plugs. It had fresh MSD wires, an aftermarket coil and the stock distributor with new electrical parts in it.
I had run the wires like I have done in the past on hundreds of different motors without issue, using wire separators and keeping them off anything hot. Never had an issue with a miss associated with wire routing before. I've had bad wires in the past that looked like a Christmas tree at night like mentioned above, but with my motor, I couldn't account for all these misfires my scanner was indicating.
I searched Google, and came up with the bulletin. Skeptical, I followed the TSB routing recommendation and rescanned the motor. All the misfires were gone after the rerouting recommended. I was surprised at the result, because I used to think of plug wire routing in a similar way as you mentioned. The difference from the way I had initially routed the wires and the way recommended in the bulletin was pretty subtle.
Here's a link to the bulletins from Magnacor's site. There are dozens more search results about the missing problems associated with these motors. Maybe the computer controlled EFI has something to do with it?
Magnacor has some expensive wires, but I've never used them. As they mention, better wires are less prone to the issue, but they still recommend following it, as it is likely prudent. Telling someone searching for a mystery miss and to discount this type of well-documented, easy fix, just because it doesn't matter what motor their wires are on just does not sound like prudent forum advice.
MAGNECOR Race Wires: Dodge "Magnum" technical bulletin
I'm just trying to help the guy with my actual experience. I know the wires don't know what motor they are on, but they do care. Ever seen how unhappy nice wires look on a Chevy or Ford?