I can't remember if the answer to this. Does adding a Pertronix electronic ignition mean you open up the spark plug gap?

 

When I added mine, I also ran the flame thrower coil and regapped at 42-45 so the spark would jump

 

Teach is right. When you add a hot coil then you can. The Pertronix by itself just replaces the points.

 

I too have the flamethrower.

I was gonna put in new plugs and when I pulled out the old ones they looked perfectly fine yet their gap was 42. This is why I asked. I might just leave the old plugs in there.

Cap and rotor were definitely beat up.

 

make sure you dont have solid core wires..they can mess up a petronic ing. ..

 

I run pertronix and a 42k coil, with the full voltage mod, I run a 40 gap with Autolite platinum plugs.

 

Pertronix says don't run solid core wires, but apparently quite a few folks do with no complaint.

Just be careful opening up spark plug gap too far, the OEM small diameter distributor cap used with point systems for example can have problems with cross fire if a 40k coil is installed and the wires and such aren't up to snuff. Spark will always shoot for the easiest path to ground, make sure the plug gap is that path, not the block or cap towers.

Supposedly the specified spark plug gap is engine dependent anyway, not based on plug or ignition type. With that said it does seem like a smoother idle results by cracking the gap open a bit with high output coil.

 

Good point Ted. That's why Ford went to the big diameter 2 piece cap in 1977 I believe. For those out there that do not know, the 2 piece cap and it's matching rotor will fit right on the ol" points Dizzy.

 

OK so should I set my gap to 40 or to the engine specific 35?

Y'all are confusing me.

 

Ah yes like my old dizzy cap setup but moved on to the HEI
Orich

 

You could try both, and see what you think. If you read the directions, Pertronix suggests opening up the gap slightly to .040" iirc, but only on installation of their Flamethrower coil? I would recommend bypassing the ballast resistor and running a Flamethrower coil, Ignitor, and a new distributor too actually.

I set the plugs in Y block to .045" just to see what's what, after I replaced all the plug wires, cap, rotor, etc. Had long run the 40K volt coil. Had previously saw crossfire at the distributor cap though, and at the coil itself, through the boots to ground. Stuffed them with dielectric grease and that went away. But a large gap at the plug can contribute to this, though

There isn't "supposed" to be any benefit from the Ignitor versus Points, technically speaking, (except for lack of required maintenance) but many people report smoother idle and better performance. Misadjusted points, worn out points - who knows.

This may also be in part due to worn distributor - the slop or wobble in the dizzy shaft and breaker plate will cause erratic timing, where an electronic pickup will be less susceptible. Probably longer dwell time is possible, I dunno. I would recommend replacing the distributor itself before adding a Pertronix though. But the Y block engine calls for .035", decided to set the plugs to .035" and then there is plenty of room for the gap to widen as they wear. Setting them first to .045" is sort of starting at the end point.