Should all C2 ballast resistors have a "tab"?

[Joe R.]

I know that some judges believe that all C2 ballast resistors should have a "tab" on the mounting flange. Below is a photo of what I believe to be the original ballast resistor from my April 67 car. Note that it has no "tab" as indicated in the adjacent drawing.

I know another owner of a very original, low mileage June 67 car that also has a ballast resistor with no tab. It seems unlikely to me that the ballast resistors on both cars have been replaced.

A review of the archives reveals previous discussions in 2000 and 2002 where members such as Jack Humphrey and Fred Oliva argued that ballast resistors without tabs were installed by the factory on some cars. Jack points out that the ballast resistor was a purchased part (not manufactured directly by Delco) and that multiple suppliers were most likely used for such a high volume critical part. However, no consensus seems to have emerged in the Tech Board discussions.

I'd like to hear from other members what the current thinking is on the "tab" issue. I'd also like to hear if there are others who believe they have original ballast resistors with no tab.

I realize that with some careful modification, my ballast resistor can acquire a tab, but I'd rather not do this if there is good evidence that at least some 67s had no tabs.

[Stephen L.]

Re: Should all C2 ballast resistors have a "tab"?

My ballast resistor is original and has no tab. 67BB

[Timothy B.]

Re: Should all C2 ballast resistors have a "tab"?

Joe,

The ballast on my very early built 67 has no tab. The car is very original and the ballast looks original to the car. I always thought someone changed it at some time but now you have me wondering.

[Joe R.]

Re: Should all C2 ballast resistors have a "tab"?

Joe,

Jack and Fred are correct. There were ballast resistors that did not have the tab. These would be the low HP including small block and big block. I have the original ballast resistors from several cars including my 67 400HP BB and they have NO tabs. Rest assured that your car has the original resistor supplied by GM from St. Louis!

Regards,

JR

[Scott Butville]

Re: Should all C2 ballast resistors have a "tab"?

I started my career in the Toolroom of one of GM's larger hardware plants in 1960 and it is from that perspective I offer the following. It is more than likely, these brackets were made on a progressive die. A typical progressive die part has some sort of "carry tab" (or tabs) which attach the actual part to the "web" as it moves through the stations in the die. Since the carry tab usually has nothing to do with the fit or function of the part, toolmakers paid no attention to it when sharpening the die and it could have been large, non-existant, or anywhere in between after each press run. A good careful toolmaker would, in fact, try to minimize it. The adjustment of the coil advance when the die is set up in the press could also have an effect on the tab. Parts of this nature were plated in a "barrel plater" and the tumbling action of that process typically softened the edges and removed or reduced things like burrs and carry tabs. It does not surprise me one bit that there are wide variations observed.

[John H.]

Re: Should all C2 ballast resistors have a "tab"?

I have what I believe to be my original resistor also, and it has no "tab" either.

[Harry Sadlock]

Re: Should all C2 ballast resistors have a "tab"?

Reading this made me curious. Went out and took a look at the my 63 250hp. I believe it is the original ballast resistor. It has a small tab as indicated by the sketch on the right.

Harry

38513

[Geoff C.]

[mike mccagh]

Re: Should all C2 ballast resistors have a "tab"?

harry: i'm of the opinion that the early midyears left st louis with tabs on their ballast resistors. also believe the c-1's also had tabs. tab configuration differs from mfgr to mfgr. believe the 67 ballast resistor lacks tabs. mike

[Michael H.]

Re: Should all C2 ballast resistors have a "tab"?

One good way to ensure that we are looking at an original resistor would be to look for signs of the factory applied black goop/sealer that would have been applied to the screw retaining the resistor to the panel. I believe all were sealed, although I suppose most of that has been removed years ago. Just a thought.....

[John daly]

Re: Should all C2 ballast resistors have a "tab"?

In a meet on Long Island last week I was told the ballast resistor should also be stamped "delco-remy" along with the tabs...we deducted for those without both....is this correct?

[Joe R.]

Re: That Tab is typical of a Progressive Die

Hi Geoffrey:

As you say, "bazillions" of these ballast resistors were manufactured over a 12 year period. However, according to Jack Humphrey, they were *not* manufactured by GM. Jack says that the drawing indicates these were a purchased part, built to a GM spec. He points out that it was unlikely that GM would sole-source a part like this, since a supply shortage would shut down multiple production lines.

Whether such a part was manufactured internally or purchased externally, the sheer volume of them suggests that they were not all made on the same tool. That leaves open the possibility that there would be variations in the appearance of the clip, especially over several years of production.

It is my impression that there are multiple examples of apparently original, non-tab ballast resistors that appeared sometime before or during the 1967 model year. However, the conventional wisdom is that *all* original C2 ballast resistors had a tab, and many judges continue to make deductions for non-tab ballast resistors. I'm not sure what it would take to get this practice to stop.

[Rick S.]

Re: Should all C2 ballast resistors have a "tab"?

Went over to the garage tonight and checked my June 67 SB and my resistor does not have the tab. I am unsure if the resistor is original to the car but by appearances it is very old. At the garage was my friends "Survivor" 64 365 hp car and it has a very short/small tab that I would guess at being approx 1/16".
I was unaware of this tab prior to this post,so typically how "big" is this tab?

[Joe R.]

Re: Should all C2 ballast resistors have a "tab"?

The tabs I have seen are pretty small, maybe 1/16 inch high and 1/4 inch wide. The top edge of the tab is flat, while the remainder of the mounting flange is curved. Sorry I didn't have a "tab" version to include in the photograph I attached to my original posting. The outline drawing that I showed should give you the general idea, though.

I note that the data you provide support the theory that by mid 1967, some ballast resistors without tabs were being installed by the factory. I don't know when the "no-tab" versions first started to show up, and I don't know what percentage of late 67 cars had them, but I have run across several 1967 cars that appear to have "no-tab" original ballast resistors.

[don 42616]

My org. 67 ballast resistor has no tab. *NM*