SAAC Forum

The Cars => 1967 Shelby GT350/500 => Topic started by: BeaterGT500 on March 27, 2021, 10:24:55 PM

Title: C5AF Distributor rebuild or upgrade?
Post by: BeaterGT500 on March 27, 2021, 10:24:55 PM
Howdy again, inching forward on my 67 500 and now I'm looking at this ratty original C5AF dual point distributor.  Anyone out there specialize in rebuilding these units?  I've never torn one down and don't really want to experiment on this one.  It's complete but crusty, and I'm not opposed to shelving it and using a modern replacement that appears close to stock, using dual ignitors instead of points.  Any ideas?
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: Bob Gaines on March 28, 2021, 12:04:18 AM
Quote from: BeaterGT500 on March 27, 2021, 10:24:55 PM
Howdy again, inching forward on my 67 500 and now I'm looking at this ratty original C5AF dual point distributor.  Anyone out there specialize in rebuilding these units?  I've never torn one down and don't really want to experiment on this one.  It's complete but crusty, and I'm not opposed to shelving it and using a modern replacement that appears close to stock, using dual ignitors instead of points.  Any ideas?
I am not aware of a modern replacement that appears stock. Rebuilding and using points is the solution if you want it to appear stock.
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: Royce Peterson on March 28, 2021, 11:23:34 AM
Several people specialize in rebuilding and recurving those distributors. You can use points (what I would do) or Pertronix sells a single Ignitor that replaces the points.


Quote from: BeaterGT500 on March 27, 2021, 10:24:55 PM
Howdy again, inching forward on my 67 500 and now I'm looking at this ratty original C5AF dual point distributor.  Anyone out there specialize in rebuilding these units?  I've never torn one down and don't really want to experiment on this one.  It's complete but crusty, and I'm not opposed to shelving it and using a modern replacement that appears close to stock, using dual ignitors instead of points.  Any ideas?
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: shelbydoug on March 28, 2021, 01:28:15 PM
That's a distributor that you want to hold on to particularly if it is date correct for your engine. It's worth at least $750 and maybe a thousand or more even if it NEEDS a rebuild, which it may not.

Don't try to clean if up, you might ruin it's value.

In proper working order, THAT is about the best distributor you can have for the car.

I'd leave the points in it. There isn't anything particularly miraculous about Petronix ignition systems.
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: Kent on March 29, 2021, 06:03:00 AM
The ignitor is interesting, because from the outside its not visible, are there really no benefits, hp gains with the ignitor?
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: shelbydoug on March 29, 2021, 07:09:34 AM
Quote from: Kent on March 29, 2021, 06:03:00 AM
The ignitor is interesting, because from the outside its not visible, are there really no benefits, hp gains with the ignitor?

I don't know of anyone who has done a scientific comparison to see if there was a power difference, but personally for me the points have been less of an issue.

I would think that if you could show a benefit performance wise with the Petronix it would be in comparing it to a single point distributor since there you likely would have greater dwell which is where the coil can generate more voltage to the plugs.

There simply is no way to make the Petronix look exactly like the single skinny wire coming out of the original distributor that I know of.


Points are not any kind of a problem. There is no issue with them. "If it isn't broken, don't fix it"/
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: SFM5S000 on March 29, 2021, 08:11:55 AM
Quote from: Kent on March 29, 2021, 06:03:00 AM
The ignitor is interesting, because from the outside its not visible, are there really no benefits, hp gains with the ignitor?

The benefits of the Pertronix is that it's maintenance free. Where as the stock points and spark quality ever so slowly deteriorates due to wear on the point blocks and arc buildup at the contacts especially when spinning the engine in the upper rpm range continually. This is not an issue if one keeps the points properly adjusted. Aka: maintenance

As Doug had mentioned. It's difficult to hide a Pertronix unit if one participates in concourse show events due to the two wires coming out of the distributor body. It just boils down to what is your priority. I so happen to prefer the maintenance free aspect. I wrapped the two wires with fusing tape. I also found a distributor cap that fits the OEM HiPo distributor with HEI male ends, but that's me.

Cheers,
~Earl J

Title: Re: C5AF Distributor rebuild or upgrade?
Post by: shelbydoug on March 29, 2021, 08:37:26 AM
Yes, the Moroso ignition set and IH distributor cap apply themselves very well.

I briefly went back to the AUTOLITE cap and wires and the set cross fired all over the place. So they look great and original and in fact might even crossfire like the originals do but the male caps do work as they are supposed to, and at $40 for the set, you can't beat them.

If you take some lacquer thinners you can wipe off all of the MOROSO advertising and it will just keep folks wondering, WTF, is going on here? That's perfect. Intellectual curiosity should not be denied.

Just make sure that you use the matching rotor with it.



I was using the Petronix in my 68 GT350 for almost ten years. So that amounts to about 800 miles. Somewhere along the line it took out my tachometer which now won't read over 1,200 rpm and was involved in some sort of hocus pocus situation on a hard start issue.

I keep a five pound "lumping hammer" handy for situations like that and it worked perfectly on dispatching the Petronix to it's ancestors.


After going through the entire, which coil deal, it wound up with a yellow top, points reinstalled, and a new pink wire. So far the lumping hammer is sleeping in it's own secure place in the shop ready for it's next inevitable recall. But not just yet...but maybe soon?

Title: Re: C5AF Distributor rebuild or upgrade?
Post by: Lfino on March 29, 2021, 08:50:40 AM
That lumping hammer sounds like a good idea. But for me, I would need two because sometimes I feel like playing a damn drum solo on these things!
Title: Re: C5AF Distributor rebuild or upgrade?
Post by: rockhouse66 on March 29, 2021, 09:48:55 AM
Sent you a PM about rebuild.