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Spark Plug Gap

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dougsmarkIII

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My 66 BJ8 has the Pertronics distributor module installed and the Pertronics Flame Thrower Ignition coil. Should the spark plug gap be changed to take advantage of this combination and what gap?

Believe the plug gap is set at .025 at this time, but am getting ready to change plugs tonight. I'll check back later for replies after the old ones are out.

Doug
 
I installed an Allison ignition system (which I think is Crane now), way back in '93 and set the points to .060

The car start up instantly, in any temperature. I think this produces so much spark you could almost cut off the protruberance (thing you move/adjust when you gap a plug).

My car is a '67 BJ8 btw.....
 
If your plug gaps are set at .060 then you must have a CD ignition system. Believe the Pertronics module just replace points and the Flame Thrower is a little hotter than stock.

I will probably increase the gap .005 to .030 on my system.

Doug
 
The adjustable bent strap off the end of the threaded portion of the spark plug is known as the Earth, Side, or Ground electrode.
 
Its been so long I forget what its called. There is a small "box" about 1/2 the size of a paperback book that is part of the system. Pretty sure this type of system is the one Moss still sells now made by Crane... All I know is this has been a great and worthwhile upgrade!
 
Wangdango,

The unit you are describing is a Capacitive Discharge Allison/Crane system. It is an optically triggered system that can handle the types of conditions produced when setting the plugs at 60 thousands. I have had the Crane version installed after my original Allison failed in about ā€™94 but have never tried setting the plug gap past 35 thousands.

I have a Pertronix installed in my Triumph and like it for its stability and ability to be hidden. I donā€™t believe it is as robust as the Crane and be able to handle extended plug gaps of the magnitude you are using.

All the best,
Ray (64BJ8P1)
 
I have run a Pertronix Ignitor (IN the distributor) module in my 1966 Mustang GT Fastback and also in my Ford 302 V8 Healey.

The Pertronix Ignitor module is NO MORE than a points replacement. It is a simple magnetic ON-OFF switch. It does nothing to enhance or change the spark.

When powered by a full 12 VDC, the Pertronix Flamethrower coil should dispense about 40 KV which will allow the plug gaps to be opened up.

I would check with Pertronix for their advice, but with a similar Mallory coil, I run my plug gaps at .045".

Tim
 
dougsmarkIII said:
My 66 BJ8 has the Pertronics distributor module installed and the Pertronics Flame Thrower Ignition coil. Should the spark plug gap be changed to take advantage of this combination and what gap?

Believe the plug gap is set at .025 at this time, but am getting ready to change plugs tonight. I'll check back later for replies after the old ones are out.

Doug
Click to expand...

I'm negative ground, pertronix, lucas sports coil.
Champion plugs are gapped at .035
 

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Roger, I am happy to learn that we use the same oil filter and have the same plug gap, but I don't have one of those frayed wires in my distributor: very un-Roger-like!

Just kidding Roger!

Lin
 
Roger,

I, too, can't believe you have a frayed wire on your car! I also wonder about those wear marks on the top of your rotor; there should only be the one point where the carbon center post presses on the rotor. It looks like something else is rubbing.
 
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