C3 brake caliper codes

[Michael L.]

Guys,

I have searched the forum already and did not see anything helpful.

I'm up to the brake system on a frame off resto of my 69 coupe. I have four rebuilt (correction: three apparent rebuilds one ? new) calipers ready to go on but they were not obtained with an NCRS build in mind. Now that I am going that way I need to know if these calipers will work. Three of them have the Delco Moraine label and two of them have matching cast codes: 5473807 on one side of each caliper and 5473806 on the other side. the other casting has 5473795 on one side and 5452273 on the other. The fourth casting has no numbers or Delco Moraine on it and I'm guessing its new. Are these numbers o.k.? I expect that the "new" one will likely need to be replaced, but what about the others? Are these numbers even looked at? What about date codes? Are there any, and are they judged? This car will be judged at some point but if I don't have to replace these that would be great.

Thanks,
Mike

[Joe L.]

Re: C3 brake caliper codes

Guys,

I have searched the forum already and did not see anything helpful.

I'm up to the brake system on a frame off resto of my 69 coupe. I have four rebuilt (correction: three apparent rebuilds one ? new) calipers ready to go on but they were not obtained with an NCRS build in mind. Now that I am going that way I need to know if these calipers will work. Three of them have the Delco Moraine label and two of them have matching cast codes: 5473807 on one side of each caliper and 5473806 on the other side. the other casting has 5473795 on one side and 5452273 on the other. The fourth casting has no numbers or Delco Moraine on it and I'm guessing its new. Are these numbers o.k.? I expect that the "new" one will likely need to be replaced, but what about the others? Are these numbers even looked at? What about date codes? Are there any, and are they judged? This car will be judged at some point but if I don't have to replace these that would be great.

Thanks,
Mike

Mike-----


The only caliper half on the car which has a correct casting number for a 1969 is the 5452273. All the others are from 73-82 models or SERVICE caliper halves. The ones with no casting numbers are likely aftermarket and not a GM casting or they're original calipers that have been modified (by grinding and smoothing; I've seen some of these).

The caliper halves for 65-72 MAY contain dates. However, if what APPEAR to be dates actually do represent a date, it's a julian date with no reference to year. Many 73-82 calipers do have a complete casting date, including year. Some are julian with year and some are conventional month, day, year with dots between the month, day, and year.

I don't think the casting numbers or dates are currently being judged, but I'm not sure about that. I don't do any judging.

[Michael L.]

Re: C3 brake caliper codes

Thanks, Joe.

Any judges out there who can tell me if these numbers matter?

Any help would be appreciated.

ML

[Alan S.]

Re: C3 brake caliper codes

Hi Michael,
I believe for 69 the calipers are looked at to determine color (low gloss black), natural machined surfaces (they're machined after painting), and zinc plated bleeder screws (the ss screws sure are pretty). There's no mention of casting numbers or dates.
This info is from the 68-69 Tech Info Manual.
The brake hoses, backing plates and caliper mounts are judged with the calipers, too.
Regards,
Alan

[Bob D.]

Re: C3 brake caliper codes

Michael,

I have judged C-3 Chassis and have not looked at casting or date codes on calipers. I do look for correct color, gloss and for the machined surfaces.

Bob

[Michael L.]

Re: C3 brake caliper codes

Thanks to all. This was very helpful.

Mike

[Michael L.]

Re: One final ? on C3 brake caliper codes

Oh, one final question. Are the bolts that hold the caliper together painted as well? Is the painting done before or after that assembly? If they are not painted, does anyone know the finish?

Thanks

[Joe L.]

Re: One final ? on C3 brake caliper codes

Oh, one final question. Are the bolts that hold the caliper together painted as well? Is the painting done before or after that assembly? If they are not painted, does anyone know the finish?

Thanks

Michael----


The caliper half clamp bolts were NOT painted. They were phosphate-finished and of GM 300M material (SAE grade 8), 6 lines.

1965-67 used PLACE BOLTS. 1968-82 use conventional hex head bolts which are trimmed (i.e. non-indented) head. No washer of any kind was used under the bolt head.

[Michael L.]

Re: C3 brake caliper codes

Thanks, Joe