Accel "Super Stock" Coil

[Omie01]

Can an Accel "Super Stock" coil be used on our cars in place of the "factory" coil? All I can find is that it is a 12v coil, but they claim the coil can be a "stock" replacement for our cars. Anybody using one? Right now I have a stock coil with 1st gen Pertronix Ignitor and everything runs well, but I read somewhere the stock coils produce around 24,000 volts, and the Accel produces in the ballpark of 40,000 volts. Would the upgrade be worth it? I run Autolite Platinum plugs, and 9mm wires, with brass dizzy cap and rotor.

 

[will e]

If it is an 'internal resistor' coil then you will need to either replace your resistor wire or use a relay. To use a relay you would trigger it with the resistor wire (which will be live when the ignition is in the on position). A relay doesn't require 12v to operate.

 

[Don C]

Because you already have the Pertronix I would just bypass the resistor wire and run it on 12 volts. Even if the Accel coil does operate at the reduced voltage the output would also be reduced.

 

[Mister 4x4]

I'm running an Accel Super Stock coil on mine with a Duraspark ignition conversion - no problems whatsoever.

http://www.summitracing.com/parts/acc-8140hv/overview/

There's an Accel Duraspark Super Stock Racing coil (same output voltage) with the correct Ford connectors (I would've gone with this one, rather than clipping and adjusting the coil-end of the Duraspark conversion harness to replace the snap-in connectors with eyelets).

http://www.summitracing.com/parts/acc-140207/overview/

My understanding is the coil voltage output is irrelevant with regards to the ignition system - it will be traveling through the coil wire, distributor cap & rotor, and on to the spark plugs only. The ignition system acts [essentially] like a big timed-circuit low-voltage relay, telling the coil when to fire - not running all that juice through the ignition system itself.

In theory, you could use a 500,000 volt coil... if you had proper isolation of the rest of the vehicle's electrical system.

 

[Don C]

An interesting thing about coils is that they just produce enough voltage to bridge the spark plug gap. The total potential voltage is governed by the saturation current in the primary windings, the winding ratio between the primary and secondary windings, and the iron core. The primary side is charged when the points are closed (or connected to ground by an electronic ignition). As soon as the points are opened (or the ground removed) the magnetic field created by the primary windings collapses almost instantly through the iron core and secondary windings creating the high voltage necessary to bridge the spark plug gap. As soon as the spark is created the field is discharged and the voltage does not get any higher.

Our cars, with a 0.35" gap and 10:1 compression, require about 12,000 volts to fire the spark plugs. The wider gaps, that came about as car makers tried to improve the efficiency, required higher voltage coils.

 

[72HCODE]

i believe i have been using an accel super stock coil with my Pertronix II ignition system.

i still use my resistance wire as the voltage drop was small anyway and i can change to points if needed. each car is different in that regard some cars need to use a bypass but otherwise every coil today is a high voltage coil anyway so even running under volt it gets over 20,000 volts to the plugs.

years ago i did use a 12v bypass wire and it caused interference with my oem radio so i ditched it and went back to the resistance wire.

if your ignition system is in good shape running under 12 volts as long as the electronic ignition doesn't care will produce more then enough spark.

many aftermarket ignitions tell you to add .05" gap to the plugs, in our cars it usually causes misfire stick with stock .35" gaping and you will be fine.

 

[barnett468]

Can an Accel "Super Stock" coil be used on our cars in place of the "factory" coil? All I can find is that it is a 12v coil, but they claim the coil can be a "stock" replacement for our cars. Anybody using one? Right now I have a stock coil with 1st gen Pertronix Ignitor and everything runs well, but I read somewhere the stock coils produce around 24,000 volts, and the Accel produces in the ballpark of 40,000 volts. Would the upgrade be worth it? I run Autolite Platinum plugs, and 9mm wires, with brass dizzy cap and rotor.

yes you can use it in place of the stock coil.

bypass the stock ignition wire as suggested.


.

increase the plug gap to .042"

 

[Omie01]

Thank you for the info gents. I think I will stick with stock coil for now. I did gap my plugs to .040 and don't seem to have any issues. Maybe the next set I will gap to .035 and see if it makes any difference.

 

[72HCODE]

the cars all react differently to the taller gap.

on my car it didn't work. a taller gap is suppose to make a leaner mix of air/fuel ignite. what i found on my car was it was causing mid throttle detonation and power loss. this could of been for a few reasons.

now the ignition companies will tell you if you are using a higher voltage coil, and do not gap taller then you will shorten the life of a spark plug. i looked at it like this if a plug is suppose to get 50,000 miles and i get 20,000 miles i still makes no difference to me if i put 2000 miles on the car every year.

even a daily driver wouldn't be that horrible with lower plug life, i can swap plugs in an hour anyway.

everyone seems to have the best overall luck with a .35 gap over a .40 or .45 ford recommended a .35 in the service manuals and .05" can make a big difference as i discovered. so as a general rule you stay at .35 because the results are known.

if you are using a super charger or turbocharger then it is a different story.

 

[Omie01]

What brand spark plug do you like for your car?

 

[Mister 4x4]

I wanted Motorcraft, but settled for Autolites.

My 1980 Jeep loves plain old standard Champions (so did my '97 Ram, of all things) - hard to beat the old school plugs for old school applications. I'd tried Bosch Platinums, Champion Truck Plugs, even Split Fires... just spent more money unnecessarily on plugs that just made it unhappy. The core of one of the Bosch Platinum plugs even came apart and closed the gap in the #4 hole for some reason (did it twice with two different plugs).

Since the Mustang came with either Motorcraft or Autolites, I went with them. If it ever becomes unhappy with that arrangement (once its properly tuned up, of course), I'll toss in some straight-up, old school Champions and go from there.

 

[Totalled]

They tend to leak within a year. IMO, MSD is a better product.