A Tale Of 3 Distributor Caps. What Do They Fit?

[Chuck G.]

I have accumulated 3 distributor caps, all slightly different. Not having access to the JG's for every year, I'd like to ask what is the consensus as to their application. Here's how they're marked on the top.

1. Delco-Remy Patent Pending R This is a NOS cap with copper terminals

2. Delco-Remy Patent 2769047 R This is a used cap with silver terminals

3. Delco-Remy AK Patent 2769047 R This is a used cap with silver terminals

What's what? All help appreciated.

Chuck

[Rob M.]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

I would like to add one more to the list for identification help. I have a used cap that is marked " Delco Remy Patent Pending" on the top, has silver terminals, and has the number 52 on the inside top adjacent to the delco remy logo. What is the application of this one?
Thanks for your help.

[Rob M.]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

I would like to add one more to the list for identification help. I have a used cap that is marked " Delco Remy Patent Pending" on the top, has silver terminals, and has the number 52 on the inside top adjacent to the delco remy logo. What is the application of this one?
Thanks for your help.

[Jack H.]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

All the caps mentioned in this thread FIT V-8 Corvette applications prior to HEI introduction. The nuissances of tinned vs. copper terminals reflect certain production changes and target applications. The changes in cap emboss Patent Pending, Pat Pending, Patent R (with or without extraneous emboss) are detailed as appropriate in the various Judging Guides (each has a 'correct' Corvette factory concours target 'fit').

There are a few more variations that you don't ask about. One is whether the 'Delco Remy' emboss is in a conventional block font or a 'stylized' script font. Plus, there are instances of all four combinations (Pat Pending with and without R; Pat No. with and without R).

I'm afraid I know we DON'T KNOW the true nature of history on this part.... I took the liberty of reving up my patent search machine and sucking down a copy of the referenced US Patent. It involves the geometry of the distributor (is centrifical advance above/below the plane of the points), the use of 'snap-in' points, the incorporation of an externally adjustable dwell feature, and the use of a dist cap with a 'window' to access the adjustable dwell feature.

The application/grant date of this patent goes WAY BACK!!! By the time we see dist caps showing up with on cars with an emboss of the form Pat No XYZ (Shark era), the patent had effectively reached the end of its life!!!!

So, from what I know about US Patent Law:

(1) Inventor must visually tag the invention with Pat Pending notice from first public disclosure until patent grant.
(2) Inventor must visually tag the invention with Pat No. after grant until the end of the patent life.

The current NCRS interpretation of what dist cap applies to what year Corvette makes NO SENSE.... But, we base our judging rules, in large part, on observations of 'untouched' original cars and we live with the current judging rules we have.

If there's anybody out there with Delco Remy work experience, I'd sure like to hear about this. As a former engineering vice president in high tech electronics skilled to a working level with patent law/proceedure, what I see in our current judging rules (started as Pat Pending emboss and stayed that way WELL after the patent was granted, then changed to Pat NO. XYZ for a few years, then changed BACK to Pat Pending) says GM 'blew' its intellectual property rights with the US Patent Office on this invention from the 'git go' OR our current judging rules are wrong/mistaken as to the chronology of events. Comments invited.

[Jack H.]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

All the caps mentioned in this thread FIT V-8 Corvette applications prior to HEI introduction. The nuissances of tinned vs. copper terminals reflect certain production changes and target applications. The changes in cap emboss Patent Pending, Pat Pending, Patent R (with or without extraneous emboss) are detailed as appropriate in the various Judging Guides (each has a 'correct' Corvette factory concours target 'fit').

There are a few more variations that you don't ask about. One is whether the 'Delco Remy' emboss is in a conventional block font or a 'stylized' script font. Plus, there are instances of all four combinations (Pat Pending with and without R; Pat No. with and without R).

I'm afraid I know we DON'T KNOW the true nature of history on this part.... I took the liberty of reving up my patent search machine and sucking down a copy of the referenced US Patent. It involves the geometry of the distributor (is centrifical advance above/below the plane of the points), the use of 'snap-in' points, the incorporation of an externally adjustable dwell feature, and the use of a dist cap with a 'window' to access the adjustable dwell feature.

The application/grant date of this patent goes WAY BACK!!! By the time we see dist caps showing up with on cars with an emboss of the form Pat No XYZ (Shark era), the patent had effectively reached the end of its life!!!!

So, from what I know about US Patent Law:

(1) Inventor must visually tag the invention with Pat Pending notice from first public disclosure until patent grant.
(2) Inventor must visually tag the invention with Pat No. after grant until the end of the patent life.

The current NCRS interpretation of what dist cap applies to what year Corvette makes NO SENSE.... But, we base our judging rules, in large part, on observations of 'untouched' original cars and we live with the current judging rules we have.

If there's anybody out there with Delco Remy work experience, I'd sure like to hear about this. As a former engineering vice president in high tech electronics skilled to a working level with patent law/proceedure, what I see in our current judging rules (started as Pat Pending emboss and stayed that way WELL after the patent was granted, then changed to Pat NO. XYZ for a few years, then changed BACK to Pat Pending) says GM 'blew' its intellectual property rights with the US Patent Office on this invention from the 'git go' OR our current judging rules are wrong/mistaken as to the chronology of events. Comments invited.

[Bill Clupper]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

I believe the only way to accurately research this is from documentation within the old Delco-Remy Organization, that would now be a part of Delphi Automotive Systems. GM was not nearly as aggressive in patent law in the '50's and 60's as it is today. The likleyhood that the patent number appeared after the patent had expired is certainly possible, if for nothing more than to scare those who did not do the patent search you did, something that would have been time consuming and expensive in the pre-computer era. I have not personally seen an example of a patent number being on a non"R" distributor, but it cetainly could be possible. One has to remember that phenolic molding is a process that for large parts such as this primarily used molds of less than ten cavities, and a one minute cycle time was not uncommon. Divide that into the 4 or 5 million units per year going into GM cars and the aftermarket, you come up with a significant amount of toling that must be revised, while still maintaining production, thus the possibility of overlap becomes quite probable.

[Bill Clupper]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

I believe the only way to accurately research this is from documentation within the old Delco-Remy Organization, that would now be a part of Delphi Automotive Systems. GM was not nearly as aggressive in patent law in the '50's and 60's as it is today. The likleyhood that the patent number appeared after the patent had expired is certainly possible, if for nothing more than to scare those who did not do the patent search you did, something that would have been time consuming and expensive in the pre-computer era. I have not personally seen an example of a patent number being on a non"R" distributor, but it cetainly could be possible. One has to remember that phenolic molding is a process that for large parts such as this primarily used molds of less than ten cavities, and a one minute cycle time was not uncommon. Divide that into the 4 or 5 million units per year going into GM cars and the aftermarket, you come up with a significant amount of toling that must be revised, while still maintaining production, thus the possibility of overlap becomes quite probable.

[Joe L.]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

Chuck and Rob------

It is not possible to positively ID the caps based upon the information provided. GENERALLY, the caps sound like the Delco 308-R and the Delco 309-R. These caps will FIT just about any 58-74 Corvette (and other Chevrolet and GM car line) distributor. There were several GM part numbers associated with the D-308-R, the last and current one being GM #12338667. The D-308-R uses aluminum terminals/rotor contacts and all that I recall having seen have been of black plastic color.

The D-309-R uses copper terminals/rotor contacts. Usually, this cap is made of a dark brown plastic material, but I have seen some that were black. As far as I know, it was of just 1 GM part number---GM #800061. It will also fit just about any 58-74 Corvette (or Chevrolet and GM car line) distributor.

The real problem in ID here is the fact that there were certain other Delco distributor caps manufactured during the 58-74 period which would include all of the features which you both described. However, these caps would, for a variety of other features, not be compatible with 58-74 Corvette distributors.

[Joe L.]

Re: A Tale Of 3 Distributor Caps. What Do They Fit

Chuck and Rob------

It is not possible to positively ID the caps based upon the information provided. GENERALLY, the caps sound like the Delco 308-R and the Delco 309-R. These caps will FIT just about any 58-74 Corvette (and other Chevrolet and GM car line) distributor. There were several GM part numbers associated with the D-308-R, the last and current one being GM #12338667. The D-308-R uses aluminum terminals/rotor contacts and all that I recall having seen have been of black plastic color.

The D-309-R uses copper terminals/rotor contacts. Usually, this cap is made of a dark brown plastic material, but I have seen some that were black. As far as I know, it was of just 1 GM part number---GM #800061. It will also fit just about any 58-74 Corvette (or Chevrolet and GM car line) distributor.

The real problem in ID here is the fact that there were certain other Delco distributor caps manufactured during the 58-74 period which would include all of the features which you both described. However, these caps would, for a variety of other features, not be compatible with 58-74 Corvette distributors.

[Robert C.]

Re: 65 cap and 68-69 guides say

In the 65 judging Guide it says; All dist. use a black plastic cap that reads; Delco-remy PATENT PENDING. Score caps that read, Delco Remy PATENT PENDING R or Delco Remy PATENT 2769047 R as a replacement cap.
In the 68-69 manual it says; All caps are Delco Remy brand on the top of the cap in raised letters and also shows "PATENT 2769047 R".
There is research being done now that dates the changes.

[Robert C.]

Re: 65 cap and 68-69 guides say

In the 65 judging Guide it says; All dist. use a black plastic cap that reads; Delco-remy PATENT PENDING. Score caps that read, Delco Remy PATENT PENDING R or Delco Remy PATENT 2769047 R as a replacement cap.
In the 68-69 manual it says; All caps are Delco Remy brand on the top of the cap in raised letters and also shows "PATENT 2769047 R".
There is research being done now that dates the changes.

[Joe L.]

Re: 65 cap and 68-69 guides say

Bob------

I can partially date the change. The D-308 was known as GM #1942654. It was used on most 1963-68 Corvettes (except FI), although it's possible that some late 68s received it's successor. The D-308-R was initially known as GM #1971244. It, or its SERVICE successor described below, was used on all PRODUCTION 69-74 Corvettes, although as previously mentioned, it may have been used on some late 68s, too.

The 1942654 D-308 was discontinued from SERVICE in October, 1969 and was replaced, for SERVICE, by the D-309-R, also known as GM #800061. Also, the GM #1971244 D-308-R was discontinued from SERVICE in February, 1969 and was also replaced, for SERVICE, by the D-309-R aka GM #800061.

Notwithstanding the above, I do not think that manufacture of the GM #1971244 cap ceased when it was replaced by the GM #800061. As far as I can tell, the cap continued to be manufactured and MAY have been used in PRODUCTION for all/some 1969-74 models. It may also have continued to be available through Delco. In 1976, it "re-emerged" as the SERVICE successor to the cap that had once-upon-a-time replaced it, the D-309-R aka GM #800061.

[Joe L.]

Re: 65 cap and 68-69 guides say

Bob------

I can partially date the change. The D-308 was known as GM #1942654. It was used on most 1963-68 Corvettes (except FI), although it's possible that some late 68s received it's successor. The D-308-R was initially known as GM #1971244. It, or its SERVICE successor described below, was used on all PRODUCTION 69-74 Corvettes, although as previously mentioned, it may have been used on some late 68s, too.

The 1942654 D-308 was discontinued from SERVICE in October, 1969 and was replaced, for SERVICE, by the D-309-R, also known as GM #800061. Also, the GM #1971244 D-308-R was discontinued from SERVICE in February, 1969 and was also replaced, for SERVICE, by the D-309-R aka GM #800061.

Notwithstanding the above, I do not think that manufacture of the GM #1971244 cap ceased when it was replaced by the GM #800061. As far as I can tell, the cap continued to be manufactured and MAY have been used in PRODUCTION for all/some 1969-74 models. It may also have continued to be available through Delco. In 1976, it "re-emerged" as the SERVICE successor to the cap that had once-upon-a-time replaced it, the D-309-R aka GM #800061.

[Terry M.]

Re: 65 cap and 68-69 guides say (not so fast) *TL*

Please be sure you are quoting from the CURRENT Technical Information Manual & Judging Guide before you post information.

Bob, your information about 1968-1969 is not reflected in the Third Edition (Summer 2001) manual.

[Terry M.]

Re: 65 cap and 68-69 guides say (not so fast) *TL*

Please be sure you are quoting from the CURRENT Technical Information Manual & Judging Guide before you post information.

Bob, your information about 1968-1969 is not reflected in the Third Edition (Summer 2001) manual.