Bypassed Ballast Resistor?

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Bluescrawler

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I recently bought a 1975 Duster with a 318. The guy that had it before me had done some work to the engine. One thing he did was put on an MSD Blaster 2 coil. I noticed, when trying to trouble shoot a starting problem (nothing happened when the key was turned) that he had a jumper going between the top poles on the ballast resistor. Basically bypassing it.

Is this standard practice?

Is there a better way to do it? I am asking because it seemed that it was causing some connection issues since after I disconnected it, cleaned the connections and put it back in place... the car started.

Here is a picture of what I am talking about.

48750372_158163394_0.jpg
 
The Blaster 2 coil with a stock mopar ecu still requires the ballast resitor to be used to ensure that you do not overheat the coil causing it to fail.
 
Why do you suppose there is a jumper between the 2 poles of the resistor?

Do you think this could be causing a problem?

I also noticed that the coil was mounted horizontally. From what I have read, these coils are oil filled and should not be mounted horizontally because they don't cool as well.

What are your thoughts?

Thanks for the reply
JO
 
The jumper was likely placed there because some one though the ballast was bad or some one said it's not necessary.

I have never heard that a coil shouldn't be mounted horizontally and it certainly does not pass my sniff test as something legitimate. Yes they are oil filled but unless it's leaking orientation isn't going to make a difference especially since as often as not they come from the factory mounted horizontally.
 
Thanks for the reply. I am going to pull the jumper and see what happens. The coil will remain exactly where it is. It turns out the MSD suggests not mounting it horizontally in the installation instructions.

I think I saw another thread with some pretty detailed instructions on testing the system for voltage related to the coil and Ballast resistor, so I'll go through that several time until I understand it and test it out thoroughly.

Thanks for your help.

JO
 
Out of curiousity do you have the Orange box? When I updated my 74 Dart right after I got it to an orange box the kit I got no longer needed to the 4 prong resistor and came with a 2 prong. I know I had to rewire it but I really don't recall off the top of my head what I did, but that jumper might just be a poor man's fix for that. If you really want to know I can take a look at my wiring tomorrow and tell you what i did to see if thats what he was tryinng to do.
 
I have heard that about not mounting those blaster 2 coils horzontal also, but I ran one that way for 2 years and never had a problem.
 
I would get an MSD-6AL, and that would get rid of ballast res. and the ing. mod, would also give the ins. of a rev. limiter,but also hotter spark.
 
Hmm....it appears that only the top has been bypassed. The lower right brown wire is the coil wire... it is NOT bypassed (if I can see the photo correctly). The dark green (top) wire goes to the ECU.....bypassing it won't get you anything as far as I know.

Check out the wiring diagrams at FBO. They may shed some better light on the matter.
 
plum360415 said:
I would get an MSD-6AL, and that would get rid of ballast res. and the ing. mod, would also give the ins. of a rev. limiter,but also hotter spark.
Click to expand...

Ditto.
 
"Originally Posted by plum360415
I would get an MSD-6AL, and that would get rid of ballast res. and the ing. mod, would also give the ins. of a rev. limiter,but also hotter spark."

Why would you do that?

#1 the ECU runs at constant battery voltage not ballasted voltage
#2 Blaster 2 coils are like the old GM points coils and when run with a ECU system it makes them operate as a High band or high resistance coil, decent with a MSD or CD ignition system but not the best choice for either.....there's way better choices out there.
#3 You basic coils are 6V that's whay you have a Ballast resistor on the run circuit, on start you feed 12V to a 6V coil and it produces way more power, of course they'll melt down if you try and maintain that much voltage for any extended length of time. The FBO Coils is a dual winding 10V coil made to produce high voltage through the seconday windings and then as resistance build through cylinder pressure and air density within the combustion chamber it sort of switches over to the primary winding and brings the voltage up to about 34KV at full load. You can run the 10V FBO Coil at 14 or battery voltage for a couple of hours with no issues, in fact we recommmend a switch be installed to bypass the ballast for racing applications. To bump the power level to about 38-40KV

I could go on and on about CD ignitions Vs ECU style, pro's con's and what works best for different applications....but your going to have to wait for the movie...or you could just by my E-book for $10.00

tech@4secondsflat.com
 
My Blaster 2 has been mounted horizontally for 15 years and has yet to exhibit any sort of problems. Currently it fires a 13.5:1 340 without any issues, so I too am inclined to not worry too much about how it's mounted...
 
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