Re: 69 BB Hood Insert fit question
They have the GM part numbers on them.
They have the GM part numbers on them.
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Re: 69 BB Hood Insert fit question
I have several sets [none for sale] and none of the GM boxes say a country of origin.
Joe, from all your posts, you have enough parts to build several cars from the ground up!!!
Ralph, I just sent you a PM regarding your moldings.
Ed
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Re: 69 BB Hood Insert fit question
The ones that were last available from GM don't fit worth a damn either. The last set I installed required a lot of grinding on the back side and bottom to fit as nicely as the originals they replaced.Comment
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Re: 69 BB Hood Insert fit question
Now that's very interesting. What do you want to bet the Chinese manufacturer reverse engineered a set of GM inserts that didn't fit right, causing the repops to fit incorrectly as well!
EdComment
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Re: 69 BB Hood Insert fit question
I highly doubt that GM ever replaced the tooling for these pieces. I fully expect that the same tooling was used from 1968 right through the time the parts were discontinued from SERVICE. As such parts go, these would have been extremely low production pieces. However, it's possible the tooling was refurbished at some point. That may be where the fitment problems originated.In Appreciation of John HinckleyComment
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Re: 69 BB Hood Insert fit question
All,
The owner of Willcox Corvette in Indiana is a friend of mine and he has a new set of original inserts in the original GM boxes and he let me see how they fit. Well, the left insert fit as badly as my repro part! Very discouraging! Since they didn't fit any better, I didn't ask him what he wanted for them. He has a large selection of NOS parts if you ever need something. Anyway, I'm not sure what the deal is but it is what it is I suppose.
Thanks for all your input on this dilemma.
BradComment
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Re: 69 BB Hood Insert fit question
Well that bites. It's pretty sad when even NOS parts don't fit! Looks like it's time for some smart cookie to reinvent the wheel. Of course, with such a small need for these, I highly doubt anyone would go through the bother and expense of development, so I guess we're stuck with what we have. So.... time to get the grinding wheel out!
EdComment
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Re: 69 BB Hood Insert fit question
All-----
Here's the thing I don't understand. It would seem to me that only 1 set of tooling would ever have existed for each of these hood inserts. I cannot imagine that there would have been enough requirement for these that more than 1 set of tooling was ever made. After the PRODUCTION requirement ended in 1972, I would expect that SERVICE pieces would have been made from the same tooling. All of these pieces would have been made from a permanent mold type of casting process with zinc diecast material. So, I do not understand why those made the last day these were manufactured would have been any different from the first ones made in 1968.In Appreciation of John HinckleyComment
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Re: 69 BB Hood Insert fit question
Joe you stated above that you have several sets of these. Do any of the boxes have dates stamped on them? If so, can you compare the earliest dated set you have with the latest dated set you have and see if there's a difference?
If not, then we're back to square one.
I'm also surprised we haven't heard more complaints on this. You would think that 68-72 owners would be screaming!
EdComment
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Re: 69 BB Hood Insert fit question
Ed-------
I compared what appears to be the most recently manufactured set of moldings I have (e.g. with bar code on the labels) with a set of original 1968 moldings I also have which are in excellent condition. There is a difference. The difference primarily involves the curvature on the outboard end of the moldings. While difficult to picture, you may be able to see the difference in the attached photo.
I also tried to test fit the new moldings in an original 1968 hood (the same one that the original moldings I have came from). The moldings would not fit properly primarily due to the fact that curved ends contacted the hood before the main section of the molding was seated. I believe it would be impossible to properly install these moldings as-is.
DSCN3274.jpgIn Appreciation of John HinckleyComment
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Re: 69 BB Hood Insert fit question
Great info Joe. So there WAS a difference between originals and service moldings.
As a matter of fact, after a little detective work, I found that the original 1968-1969 part numbers (3922285-6) shown in the 1968 and 1969 AIM's were superseded by 3929259-60 in March, 1968 (see attached from the 1973 P&A 30H - Parts History Catalog, dated January, 1973)! This is very strange since the 1969 AIM still shows 3922285-6 for the moldings. You would think that by March, 1968, the 1969 AIM would have reflected the new part numbers, but no. Even the 1970 AIM shows 3922285-6 for the moldings, so when did the change ACTUALLY take place? I don't have a 1971 or 1972 AIM, so maybe someone with one of those can chime in.
Now, as for the differences, since the part number changed, that means the casting changed somehow. What exactly changed and why? I've always been under the assumption that the 1968-1972 big block (and LT-1) hoods were the same (exterior wise) and the moldings would fit any of the years, but if something DID change in the molding location on the hood, then that might explain the change in the part numbers.
The repops are probably based on the 3929259-60 parts, and if that's the case, they may not fit correctly on a 1968-1970 hood? I'd really like to know when the AIM reflected the new part number and if there are any notes associated with them.
It's yet ANOTHER mystery!
EdComment
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Re: 69 BB Hood Insert fit question
Well then, when the heck did the 3929259-60 moldings make their debut and why? Obviously the date in the P&A 30H is wrong.
EdComment
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Re: 69 BB Hood Insert fit question
Okay, after thinking about this for a while, I believe the part numbers changed, but only in a service environment because they now included the speed nuts. (Original production line parts didn't include the nuts.) Joe, do your NOS sets have speed nuts included? If so, that's the reason.
The big question is... Are the CASTING NUMBERS the same between the original 1968 set you have and the NOS sets you have? If they're the same casting numbers, then NOTHING changed (although, as shown in Joe's picture above, something obviously DID change), but if they're different, then yes, they changed, but why?.
EdComment
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