C2: AIM wrong, Judges Correct!

[Alan Drake]

Owners of 63/64 are aware of many disagreements with the JG and the real thing. However when the AIM is incorrect and the JG knows the right thing:

Credit Needs to Be Given!

I'm referencing to page D145 of the 64 AIM that appears to show the voltage regulator mounted on the wheel well inner fender. Now, I have never seen such a location for an original 64, instead its mounted on the radiator support and a judge does not take off any points for that's what the JG calls for.

Dispite the extensive information found in the JG, 64's seem to have had many changes making it difficult to write a good JG. Note the 63's appear to be even worst! My own opinion is that the 63 and 64 should be stand alone JGs, but I'm not the one that has to work on the new JG - always much easier to toss stones.

[Chuck Sangerhausen (20817)]

Re: C2: AIM wrong, Judges Correct!

Typically, most reproduced AIM versions only reflect one snapshot in time, and in many model years, the reproduction is the last AIM version at the END of the model year...ALL THE EARLIER RUNNING CHANGES WILL NOT BE SHOWN. The first step in the event of such conflict is to determine what time snapshot the AIM actually represents by looking at the latest issue dates on the sheets.

This weakness is not necessarily fatal to a good restoration if one refuses to accept the conflict between the car, the AIM, and the TIM&JG. It does require the curiousity to research changes that occured during the model year, and this usually also means looking at a LOT of cars. In these cases, writing a single judging guide that accurately represents all the running changes in any single model year may be virtually impossible without incredible effort and/or knowledge.

The guys that write the judging guides don't get enough credit in my opinion. But...knowing how the AIMS repros were done, and what can happen to an old Corvette over 40 plus years, it would just be much easier if we could avoid these contentious arguments: Oh, that we could just go up on the Holy Mountain, and bring down the answers burned into stone slabs, with our faces glowing unnaturally.

[Art Armstrong (7674)]

Re: C2: AIM wrong, Judges Correct!

"Typically, most reproduced AIM versions only reflect one snapshot in time, and in many model years, the reproduction is the last AIM version at the END of the model year...ALL THE EARLIER RUNNING CHANGES WILL NOT BE SHOWN. The first step in the event of such conflict is to determine what time snapshot the AIM actually represents by looking at the latest issue dates on the sheets. "

Chuck, The AIM reproductions available DID NOT reflect the END (last} version of the model year. How do I know you might ask?, well it is because I was there and helped box the manuals that were sent to Mid America (at least I'm pretty sure that it was MA, but it was in the early 70s and I can't remember what I had for lunch) and the hard copy binders that we shipped were just some "extra" copies that were in the Engineering Records Retention Dept gathering dust. These AIM's were NOT complete and to make matters worse, the people that received them had NO idea what they were or how to interpret them or how they were to be organized, that's why they put page numbers on them. There were many revisions to the revision record section AFTER the ones shown on the reproduced versions.

The MASTER AIM (with ALL revisions) copies are at least three times the size of the reproduced versions.

I've said this before and I'll keep saying it........................THE REPRODUCED versions should not be relied on as AN AUTHORITY document for the TIM or JG. They are great for reference, but that's all.

That's my opinion and I'm sticking to it!

Art

[Chuck Sangerhausen (20817)]

Re: C2: AIM wrong, Judges Correct!

"I've said this before and I'll keep saying it........................THE REPRODUCED versions should not be relied on as AN AUTHORITY document for the TIM or JG. They are great for reference, but that's all."

Art, I would never argue with someone that was "there". Your comments are enlightening, and indicate that no general conclusions can be drawn about any given year AIM repro representing a "point in time" as I had assumed. However, it seems that a student of the AIM wouldn't take long to figure out if his applicable AIM is a collection of chronilogically disjointed sheets, or if it "hangs together" with contemporary consistency.

If what you're saying is true, then I'm not sure that most repro AIMs can really even be considered valuable as a reference...they could only be considered as a hodge-podge of sheets, with EACH such sheet having been correct at some point during the model year. If the "COMPLETE" Master AIMs included sheets documenting all the prior configurations before running changes, that would understandably make them "three times the size". Unfortunately, the Master AIMs sound like the "Holy Mountain" that I desire.

All I know is that the 70 AIM repro I have from Mid-America is SO LATE, that some changes made to the 70 AIM never even made it into production for 70 Corvettes. As far as I know, some changes in the repro AIM showed up only later on 71 production...fewer than 300 1970 units were made after my car. One example: My July 30 coupe has rubber vacuum hoses across the firewall with the wiper door relay mounted on the driver side; the hard pipe vacuum tubes with the relay on the passenger side shown in the repro 70 AIM didn't show up until the 71 model year (again, AFAIK).

My repro 70 AIM is otherwise fairly consistent, showing changes made to the air cleaners, ignition shielding, and ground strap elimination that occurred fairly late in the model year. If we had not had 70-72 TIM&JG committees that were familiar with those late changes, and the repro AIM being consistent with those changes, it's quite possible our TIM&JG might be insisting that only open air cleaners were used on all small block engines, and the distributor shielding used was a two piece box assembled with wing nuts. Fortunately, both configurations of these are covered in the 70-72 TIM&JG, with the late configurations being consistent with the repro 70 AIM and my very late car.

I guess what I'm trying to say is...there is NO simplistic answer to the question of which is correct, the TIM&JG or the repro AIMs. That may explain the vociferousness of these arguments concerning some model years. I have not walked in the shoes of 63/64 restorers, but I can't imagine these issues can not be resolved by diligent study of whatever is available as an AIM and the available Bowtie cars...Are there NO 63/64 Bowtie cars to study?

I guess we 70-72 guys are spoiled and missing out on the adventures of restoring a 63/64. Our TIM&JG has been an excellent reference since the second edition. I wouldn't say that I always agreed with what the 70-72 TIM&JG said, but most of those conflicts were resolved in later editions. The bottom line...I'm NOT going to change anything I found on my car that I thought to be original, REGARDLESS of what the TIM&JG says...the differences from the repro AIM that I know of are well documented among those that judge the cars.

If my car doesn't match the rest of the TIM&JG "cookie cutter" cars, then I'll take the judging hit if it's ever judged. Anyone read Bob Baird's article in latest The Corvette Restorer?...It's titled "The Cautious Approach To Restoration - Correct Or Typical?" Read it and heed it...Dr. Baird has it right.

[Art Armstrong (7674)]

Re: C2: AIM wrong, Judges Correct!

Chuck, I'm not knocking the TIM&JG as such or even saying that the repro AIMs are not valid, what I'm trying to say is that quite often too much is expected of a reproduced document that is incomplete.

Yes, the AIM MASTER copies do have every sheet with every change that occurred. The Records Retention department was on distribution for all vehicle line AIMs. They were the only group that was instructed to KEEP all of the sheets, whereas the plants were instructed to discard the sheet that was getting a new sheet. The RR dept accumulated these sheet until after the MY was over and then they ran them thru a 16mm filming process right there in their office and ended up with a roll of film with a COMPLETE history of AIM sheet issued for each vehicle line.

If you look at each AIM sheets title block and specifically at the Auth column, you will see a 5 digit number, that is the ECR (Engineering Change Request) number that authorized that change.........................if we could only get our hands on those documents, we COULD answer EVERY question that has ever come up regarding our quest for detailed information. The ECR was a very detailed document and itemized almost every aspect of EVERY RELEASED PART.

The other document that was used was called an NPC (Notice of Production Change) and it was used to keep track of critical changes that Engineering deemed necessary to notify the plants of a critical change ASAP. It was usually followed up, but not always, with a new AIM sheet for that item.

Yes, I agree, Dr Bob Baird's article had a lot of merit.

Art

[Jack Humphrey (17100)]

Follow-up question, maestro....

Once in a while I've run across an aftermarket AIM book where the individual drawings are B-size (they're folded to fit in a standard 8.5x11 booklet) vs. the more common A-size version. In those books, the quality of the drawings was OUTSTANDINGLY crisp/clear versus the fuzzy and incomplete renditions typical of the A-sized books.

What format were the drawings in the factory original books that were distributed & maintained for in-plant reference?

[John Hinckley (29964)]

Re: Follow-up question, maestro....

Jack -

The original initial issue A.I.M. sheets and subsequent revisions sent to the plants for use on the floor were ordinary 8-1/2" x 11" sheets, pre-punched for a 3-ring binder.

[Jack Humphrey (17100)]

Hum...

The one reproduction AIM book I saw (two separate instances of encounter) was for 1961 Corvettes and was REALLY old, originally purchased from our 'friend' Terry McCallis when he ran his parts business down in Toledo... Both of these books had VERY nice, fold out, B-size drawings in them that were CRYSTAL clear in terms of detail. That suggests a different source document was copied....

[Chuck Sangerhausen (20817)]

Re: Follow-up question, maestro....

John or Art will probably know for sure, but it's likely that the original drawings were a larger sheet (C or D), and were then reduced by reprographics to the more convenient 8 1/2 X 11 size for desk binders using an AIM title block.

Some of the detail in the sketches would be really be tedious on a 8 1/2 X 11 drawing sheet, and unnecessary if it could be drawn larger and then reduced. Perhaps the "different" source document was not actually a different drawing, but a different incarnation (size) of the same drawing from another source besides the desk binders.

[Art Armstrong (7674)]

Re: Follow-up question, maestro....

Hey guys hold your pants on, I'm typing as fast as I can to formulate a respond to a very complex item................

Art

[Art Armstrong (7674)]

Re: Follow-up question, maestro....

Lets start from the beginning:

The 1953 was not a manual as such, each operation (sheet) was drawn in drafting and given it's own part number and most were drawn on A and B size drawing formats. They weren't assembled into a manual as was done in later years.......more on that later. Yes the B size drawings were folded into a 8 1/2 X 11 size when they were shipped to the plant.

The 54 thru 56 were pretty much the same except they were compiled into a book format, but it wasn't called an AIM, it was just called the Corvette Instruction Manual.

In 57 it started to take on the look and feel of what we all call AIMs, even thought it was still called the CIM . BTW as of 1957 the part numbering of each sheet was discontinued and the manual was given just one part number. The contents were now arranged into what was called the UPC order, section 0, 1, etc. There were SOME B size images still used, but they were reduced in size to fit the 8 1/2 X 11 format and put into 3 ring binders. This format continued until the demise of the A.I.M.s in the early 80s. I don't recall seeing ANY fold outs in GMs original copies after 57, so if you did see some, they probably were from another source.

Another BTW, the quality of the original manuals sent to the plants was first class, done in-house on professional type printing presses.

When AM was given the books, they did not have exclusive use of them, so if another source wanted to sell A.I.M.s all they had to do was get a manual from AM, put their own logo on , re-number them the way they wanted, and sell them. This was of course before EM came to be. Actually AM was directed by GM to mask off the change blocks when they reproduced them, but as we all know that didn't happen and at the time GM made the decision not to pursue it.

Art

[Henry Jakubiec (33095)]

Re: Follow-up question, maestro....

Where are the Master AIM's today? Assuming that they still exist somewhere, what would it take to make them available?

[Art Armstrong (7674)]

Re: Follow-up question, maestro....

Henry, as far as I know and with all the changes at GM since I retired, I can't be certain, but I THINK they still have them stuffed away in a file cabinet. There were rolls and rolls of them. Just after I left, GM implemented a new and very complex computerized storage and retrieval system for all their documents..............new and old ones. However I don't think that their was anyway for the company, that GM hired to manage their new system, could figure out a way to convert the 16MM film to computer images and still be able to retrieve them.

If you have any influence with anyone towards the top of the food chain at GM that can authorize the "borrowing" of said film, for about a week, PLEASE let me know and I will take care of the rest.

Art

[Terry McManmon (3966)]

Re: Follow-up question, maestro....

As you know Art, I tried a couple of years ago and got nowhere. I found it kind of like talking to the wall.