Pertronix Distributor Gear

[Timmy390]

I find it odd if you go to the Pertronix site, they do not sell any distributor gears but brass.

No composite, steel or cast gears listed.

Tim

 

[707Bronk]

I find it odd if you go to the Pertronix site, they do not sell any distributor gears but brass.

No composite, steel or cast gears listed.

Tim

That was what I was hoping to ask them about today when I called, but didn't have the time to wait on hold.

And, because Pertronix billet distributors use a 0.50" shaft, replacments for 351W (and 302/289 I assume also) are hard to find at aftermarket places as well. I have found brass ones, but no iron or composites anywhere for a 351W with a 0.50" distributor shaft.

 

[jdbronco]

When I contacted them about the one for my 302 this is what they told me. It isn't directly the same but probably similar for the 351. Hope this helps, I didn't want to risk it with my new motor so I went with a reman distributor and just put their pertronix II in it.

"I am looking at purchasing D130710 for my application but I can't tell if
the distributor gear is for a roller or flat tappet cam. Can you tell me
which it is for?

The gear is a hardened steel gear on our distributor. Should be no issue for
roller cam.

Thanks for your response. Do you offer one with an iron gear for a flat tappet cam?

Nope!
Just the hardened steel gear and the bronze gear."

 

[DirtDonk]

Whelp... Guess the answer all depends on who you're talking to then.
My guy just read it out of the notes and agreed that it should be fine for an older, non-billet cam.

Wonder who we can talk to there to get to the bottom of this.
And like someone said, why would they make distributors for older engines ONLY for use with retrofitted roller cams?
Strange.

My understanding is that the optional Bronze gears from some companies, along with hard steel and some other special synthetics from other companies, were all for use with later roller cams.
They're available from Pertronix as well as MSD and (previously) Mallory for exactly this reason. To replace a cast steel gear when swapping in a roller cam into an earlier engine.

Maybe they came up with a material that was compatible with both, but forgot to tell their tech people.%)

Paul

 

[707Bronk]

I just spoke to Carl at Pertronix and he confirmed it was a hardened steel gear. I then asked if it was a melonizing process and he said is was not a melonizing process.

He also said that they have sold these distributors for over ten years with the hardened steel gear and they have not heard of any issues with wear issues on cast iron flat tappet camshafts.

I also got an email from Comp Cams confirming what I suspected:
"That is a cast iron camshaft. You can use a standard cast gear, a melonized gear, or a composite gear. The standard cast gear would be the best choice." - Thanks, Johnathan

I would think that Pertronix (or the vendors that sell them) would have a ton of complaints from customers with flat tappet cams if their hardened steel drive gear was destroying cam shafts, but this doesn't appear to be the case.

If it was major issue for Pertronix, one would think they would have done the simple thing and have cast iron or composite gears made up for them. But Pertronix says the only other gear they sell is a bronze gear.

I am unfamiliar with the melonizing process and how it is different than other hardening processes (I'll have to look into it), but Comp Cams and other literature I have read says that hardened steel are not compatible with (cast iron) flat tappet cams, but melonized gears are compatible.

Perhaps the reason why Pertronix isn't having a ton of complaints is because they actually do use a melonizing hardening process and don't know it?

I don't know, I'm at a loss. I kind of feel that if it was an issue then it would be well known by now. At the same time, now is the time to make a change before any potential damage is done. Maybe run it for another 500 miles and pull it and check?

 

[DirtDonk]

Might as well. As you said, we've got many (probably not hundreds, but certainly close) out there and so far no abnormal wear complaints. I bet Summit and Jeg's have thousands, and the forums would be alive with chatter about failed gears. One would think anyway... Can't always go by what you hear (or don't hear) on the internet!
When I read about improper gear materials being used, the wear is generally severe and generally right away. Like totally toast in a few hundred miles. Certainly not more than 1000 or so if I remember.

I've got a close friend who's Bronco we rebuilt and he's using one in his 351 with about 3000 miles on it so far with no apparent ill effects.
Most of my other buddies are running EFI now, so I don't have close contact with most of the ones we've sold over the years.
But like you said, so far no complaints. And in this case, no news is indeed good news.

When in doubt though, the method put forth earlier about using a stock (new) distributor with the Ignitor module kit installed would be one way to guarantee compatibility.

Paul

 

[707Bronk]

Thanks DirtDonk.

I'll run it for another 500miles or so and report back. It would be good for you and others to know.