Engine Electrical question... on a Mopar... go figure!!!

[dodge_em]

I have replaced the points distributor with a MP electronic ignition kit on my '68 GTX. It ran well, and then the motor was pulled and re-done. While putting it back together, the "+" and "-" wires were swapped accidentally on the coil. And the engine ran a few times that way. The wires were re-done. Since then, there is a very loud buzzing coming from under the distributor cap. Anyone know what this is? Is it fixable? Also, there is a loud popping through the exhaust under load. Right now, the car is running through open headers, so the popping is "gunshot" loud. For what it is worth, I have TTI Cermaic headers and the soft copper header gaskets, so I don't believe there is a leak at the head that is causing cold air to enter the exhaust stream. Could this problem in the distributor be causing the popping as well? I am going to replace the plugs one more time, and I have just installed brand new MP 8mm wires. I have a blaster coil. If the distributor needs to be replaced, I am considering going with a different setup and was wondering what you guys thought of the Crane HI-6 setup, or the MSD 6AL, and also what distributor you would recommend? Billet? Any thoughts on the Petronix system? Sorry for the long windedness.

Thanks for any and all help...
Craig

[cuda367]

My guess would be that the buzzing noise is spark jumping inside the dist. The carbon tower or the rotor to cap areas are the first two places to look and it wouldn't surprise me that once that is cleared up so will the popping from the exhaust.

[JVMopar]

Is the "buzzing" constant? I had a MP electronic conversion kit. I put it into a '89 dakota 360. All it would do was constantly shoot a spark out of the coil. I tried a different distributor and the problem was solved for about 3 minutes. The pickup coil in the distributors got screwed up. I ended up just getting a points distributor and one wire later no problems. I never did figure out why the pickup coils went bad.

[cuda66273]

Both the MSD and Crane HI6 units are top quality pieces. I run the Crane system right now but have run MSD for years. I changed because of the great tech support of Crane, MSD has seemed to forgotten about customer service....

The MP perfromance distributor seems to work pretty good for me, although we reworked it and curved it for our application. Before we did that it was marginal at best.

The Petronix system is alright for a cheap conversion but I don't think it really has a place on the race track.

[Jims451]

The problem is either the pickup in the distribitor or the ignition coil. Putting the wires on the wrong terminals of the coil should not affect the electronic box.

The Milti-spark Capacitive Discharge ignitions (MSD, Crane) are much better than the Mopar Box or the Petronix box. The MSD, or Crane HI-6 should make the car start and idle better. Most multi-spark benifit of these boxes occurs below 3,000 RPM. Above 3,000 RPM you only get one strong spark. This is not a limitation of the box, but the distribitor cap and coil. At higher RPMs there is only time for one spark before the distribitor rotor has moved to the next cylinder. Trying to fire multiple sparks with this limitation would cause cross fire and would ignite the next cylinder too early. This is why it is recommended to check the phasing of the cap/rotor with the spark timing.

[badcaruda]

Sounds like the pickup is de-polerized try changing the pick-up. If that does'nt do it go to a hall effect sensor like the Petronix.

[440Ramcharger]

The gunshot backfire sounds familiar. I just had (yesterday) a coil go bad. Running a Ramcharger with a 440 and the standard 1983 electronics with MP distributor and orange box. Driving down the freeway, it started cutting out. I thought the mechanical fuel pump was going out. Rolled off into a gas station and it died. It restarted several times, but gave off a loud (shotgun loud) backfire. Ended up splitting the muffler on the driver's side at the seam. This is one of the .060" thick welded ends type of muffler.
I carry an extra fuel pump and factory coil with me, and with the coil being the easier to change, decided to go that direction first. It fired up fine and idled like normal. The coil was a one month old Pertronix Flame Thrower that is epoxy filled. This is supposed to be the coil of choice for vibration of a truck, with no oil to leak out and 40k of voltage.

[PRO]

As far as this poll goes for a daily driven car with less than 10:1 compression the mp ignition is your "best buy" while it wont hurt ot have a Crane or MSD it could be considered overkill.Are you sure you have the coil wired properly? if you have the + and - swapped itll do strange things,actually the spark will originate from the ground path(ground electrode)and then travel to the center electrode(backwards).To check turn the key on with the box unplugged whichever wire is hot is the one for the + side,also be sure your pickup coil is wired correctly too,if its backwards its input to the box will be too low to properly trigger the spark.........PRO.....

[salarguy]

You have forgotten one important player in your post,Accel 300+. I have installed one in my '97 Ram 5.9l 4x4,that I'm happy with. Two side effects are;1 a slight buzz which is coming from" Da Box"
Stethascope says.(source can't be traced with the human ear) My educated guess tells me this is the rise and collapse of the capacitors. and 2. a 2-4 revolution run-on when the key is turned off, similar to my old c/mp Camaro w/ Accel's race only BEI(caused by the very Multispark you thought was so great) Get the best cap and rotor you can find. Shake the high resistance wires that keep your stereo clean. Go with MSD superconducter8.5, best of both worlds. I'm thrilled with the results, even the improved throttle response and fuel economy. All the other brands are good products too, but I'm not real sure about Crane. Their Tech didn't know if my tach would work or not.
Salarguy

[cuda66273]

Just for $hit$ and grin$...can you swap the wires coming from the distributor 180? I can't remember if the Mopar distributor will let you do this but if you can swap then around and see what happens.

It'll run like a champ or it'll get worse.

[goldcharger]

when a friend of mine and i were putting the gine back in his road runner his did the same thing mp kit brand new it was the box in that case buzzed like crazy had real hot spark thou curled my damb hair it did ha ha

[PRO]

OLD POST NEVER DIE!!! Well almost,if its an orange box its a factory defect,return it,symptoms include constant sparking even with just the key in the on position...........PRO.........