WHO'S RUNNING AN MSD BOX WITH A DURASPARK SYSTEM ?

Which box are you using to replace the factory spark box? I'm using the stock Duraspark system in my 77 Comet, but so far, I'm not at all satisfied with it, compared to the Pertronix II and Crane XR-1 I've used in my 89 Ranger. I did pick up some better results with a wire swap ( to Ford Racing 9mm's) and a Blaster 3 coil. Haven't run it enough to tell if that's going to clear up the missfire it was getting though. It did sound somewhat better though. Hopefully I'll get the oil pan leaks fixed enough this weekend to allow some street running to burn off some of the carbon on the plugs.

Does it plug into the stock wiring, or do you have to make changes ?

ratio411 said:

I used to run a 6A on mine too.
Ran great.
I did my own wiring, but a pigtail harness would make it easy.

You have a misfire?

What gap are you running?
Do you use an electronic specific coil?
What color grommet does your box have?
Does your distributor have a single or dual can advance unit?
Do you still have the vacuum delay units in the lines?
How much advance are you running on the balancer?

Click to expand...

Plug gap is around .040. I think the coil was part of the problem, seems to have smoothed out with the Blaster 3. That and the plug wires I had on it (Advance Auto EFI wire set I bought to run the motor on my engine stand last year) I'll have to check the spark box for grommet color, never paid attention to that. It's the box that came in the car when i bought it last year. Distributor is a reman 85 Stang Duraspark unit with single vacuum pod. Vacuum is connected straight to the center carb's metering block of the 6-pack. Timing is set at 12*BTDC. The new wires are Ford racing 9mm's, some of the miss may have been the #'s 3 & 7 being to close to the front carb and could have been arcing with the cheap wires. Never had a problem with this before when the motor was in my Ranger (same induction & 9mm wires then ) I just recalled some of y'all mentioning running an MSD box in place of the factory unit, that's what piqued my interest.

Blue Grommet where the wires pass into the bottom of the box.

Got to road test it this afternoon, the mis-fire cleared up with the Blaster 3 coil and new wires. Did a few short burnouts, the last one I did lured the local Sherriffs Deputy in short order. Wasn't two minutes after I pulled into a freind's driveway that he came cruisin by. Still got an oil drip from the front radius of the pan though. And the rear suspension is "squirrally" I think maybe my pushing the leafs toward each other wasn't a good thing to do when I swapped rears. I'm going to loosen the U bolts later and push em outward and see what that does.