Wider Spark Plug Gap with Pertronix Ignition?
 

I'm going to swap the old points and condenser for a Pertronix Ignitor II system. One of my friends told me that I should widen the spark plug gap. Do you all agree? And if so, what should the new gap be?

Thanks!

False. The pertronix unit is not an HEI unit. The spark is the same intensity as with the points.

:iagree: Keep it at .035". Wider gaps are good for lean emissions tuned engines but not helping you with a regular HP application.

Try it both ways and see for yourself. It's free. :)

-Mark.

:iagree:

I ran one for a couple of years and found .035 to be fine - nothing gained with a wider gap at all. It will run fine till the Pertronix up and dies on you.......

The gap is based on the capabilities of the coil/ignition system. If you haven't changed the coil, don't change the gap.

Good point. Standard advice is to keep your old points and condenser with you at all times for an emergency roadside repair.

I couldn't think of a better storage place for mine other than inside the distributor- where I couldn't lose or forget them. I did have to remove the pertronix piece to make room but amazingly, the car runs perfectly without it, year after year.

Who knew?:rofl:

Hey, Mike. You're killing me here. :rofl:

I love it! :yesnod::yesnod:
:thumbs:

Not only that, but I now had the problem of where to store the removed pertronix unit, as that had now become my emergency back up unit for when the points and condenser failed unexpectedly.

Well that was a long long time ago and I'm still waiting for an unexpected failure so I finally put the petronix unit back in a box and stuck it on my 'waste of money, what was I thinking' shelf in the garage. It's getting very crowded there. :thumbs:

Why not go with a tach drive HEI unit? I did. its very affordable and the performance is unreal!!

I realize the Pertronix kit will not improve performance. Only a true conversion to HEI will. However, I decided not to convert to HEI because it will change the stock appearance of my engine. I'm switching to Pertronix purely to remove the maintenance of points/condenser. It's not a huge expense and I thought it would be worth a try. I don't put a lot of miles on this car and I'm assuming the Pertronix reliability will be acceptable.

I'm also going to change the coil to the Pertronix model called the Flame-Thrower II, which is rated at 45,000 volts. Given this, should I still keep the spark plug gap at 0.035"?

Thanks for all your help.

I have a pertronix unit in a non vette aplication, been in for several years and it has given no problems at all. I don't care what anybody says , it starts easier , idles better.... in short does everything better than points. and you keep the stock look. its been several years but i think my plug gap is .045............not 100% sure though.

There is HEI system under the shield.you could almost retain the stock look if you wanted to.

http://i35.tinypic.com/2wgestz.jpg

i dont have a pertronix on my vette yet but my 68 mustang has had one for 6 years now and it cranks within 2 spins every time and has never faltered.

as far as a wider gap. doesnt the pertronix require a full 12v and a full 12v coil instead of the 6v coil that is oem. which would allow a wider gap on the plug.

the only reason why i dont have one in my vette yet is because i see multiple ones listed for the vette and i am not sure which one is better.

The 45,000 volt rating is essentially meaningless. This is only an indication of the insulation/dielectric strength of the coil's construction, not an indication of what happens in the cylinder. This 45kV rating also tells you nothing about the coil's resistance or inductance, which are key elements in determining the amount of energy (the KEY element of interest in coil choice) the coil can store each dwell period. And, unless the coil has an extremely high turns ratio, most likely the module driver transistor will break down before the coil reaches that level. And, for all intents and purposes, most plug voltages rarely exceed 30-35kV under worst case conditions. Just remember, voltage and energy are two different things.

The stock coils used for point-style ignition is much weaker than the Petronix Flamethrower. Pre 1974 coils ran off 5-8 volts with the use of a resistor wire or a ballast resistor. Too much juice would fry the contacts in the points assy. The Flamethrower coil needs the full 12v which means more juice to plugs.

Also, the Flamethrower and Ignitor combo will rev way past what a single points set-up will. I've had it up to 7000 RPM in a 327 car without missing a beat. A dual-point distributor will barely do 7000 and no way will typical single points system go 7000.

If RPM is HP, then the Ignitor is definetly a performance upgrade.

Plus, I'm going to guess tens of thousands of these units have been sold and the failure rate is low.

FWIW.

not true
the stock, single points distributor on my '65 I've had often at the 6500rpm redline without missing a beat and a few times I've had the car well beyond that with the tach buried which put it at 7500rpm without missing a beat, no points float, and still pulling strong.
This is a 100% stock L76 327/365hp motor.


but not as low as the failure rate of points.......... of which millions have been sold and used over decades with great reliability.

You're correct on both 'points' Barry- but I believe you're wasting your time. Many people would rather believe in marketing cra*p than common sense and experience. :thumbs:

yeah, I'm well aware of that but I still wanted to get my $.02 in.
i've beat this point to death on WAY too many threads but people still insist on wasting their money on these conversion kits regardless.
I truely believe the ONLY people that really benefit from these kits are the vendors selling them.
And for the people that say they have seen an improvement in easier starting, better idle, or better performance, they would have seen the identical improvement by simply overhauling/rebuilding their point distributor back to correct tolerances. The conversion kits are simply masking overriding problems in the distributor such as too much endplay on the mainshaft causing dwell to fluctuate, etc
The ironic part is that generally it would have cost them LESS to rebuild the distributor than the electronic conversion kits cost them and they'd have overall better reliability with the stock points. Go figure!
As for less maintenance, if taking an extra 5 minutes once a year to check and set dwell when checking and setting timing during your annual "Spring tune-up" is too much extra work than they probably shouldn't be owning an older classic car anyway - buy a new C6 and just drive it. :rolleyes:

Hmmm, wonder how many responses I'll get from THIS response. I'm sure it ain't gonna be pretty! :D

Mike and Barry, FWIW...I listened. I was getting rid of the non-original TI system in my car and was considering a Pertronix (based on the hype) but I read some of your past posts and decided to go with an overhauled points distributor. Car starts and runs perfect.