68-69 Underbody Insulation panels
Thread Starter
Le Mans Master
Joined: Aug 2000
Posts: 9,662
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From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Some 68 and 69 models were equiped with fiberglass underbody insulation. This insulation was under the floorpan on each side of the transmission tunnel. It was held in place by riveted clips similar the the clips that hold the transmisson tunnel insulator.
My car originally had this insulation which some previous owner removed. Most of the clips were removed and the rivet holes filled with silicon sealer.
Does anyone have a picture of how the insulation was installed and the correct location of the clips. I have looked in the AIM and can find no reference to this insulation. I don't remember seeing anything in the NCRS judging guide either.
Thanks
My car originally had this insulation which some previous owner removed. Most of the clips were removed and the rivet holes filled with silicon sealer.
Does anyone have a picture of how the insulation was installed and the correct location of the clips. I have looked in the AIM and can find no reference to this insulation. I don't remember seeing anything in the NCRS judging guide either.
Thanks
Safety Car
Joined: Jul 2001
Posts: 4,456
Likes: 6
From: Spicewood, Texas, USA TX-Texas
Steve, I am most familiar with 70-72, but maybe I can give you lead.
It's unbelieveable that neither the AIM, or the judging manual mention the insulation shields, since they are so prominent, BWDIK.
Vendor's catalogs are one of the best references, and the cost is free or nominal (If they can't tell you what it is, they can't sell it). I will email you a link, but if you saw Tom73's post about the "shift lock" cable, the scoop is in the same catalog, p.108.
[This message has been edited by Chuck Sangerhausen (edited 07-31-2001).]
It's unbelieveable that neither the AIM, or the judging manual mention the insulation shields, since they are so prominent, BWDIK.
Vendor's catalogs are one of the best references, and the cost is free or nominal (If they can't tell you what it is, they can't sell it). I will email you a link, but if you saw Tom73's post about the "shift lock" cable, the scoop is in the same catalog, p.108.
[This message has been edited by Chuck Sangerhausen (edited 07-31-2001).]
Team Owner
Joined: Jun 2000
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From: Southbound
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Smoke -- the underbody blanket insulation and installation of it are in my '68 AIM. Most of the real stuff is gone now from under my '68, but enough wisps and stands remain to assure me it was under there at one time. My Time/Build date is April 20, 1968.
Race Director
Joined: Apr 1999
Posts: 10,866
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From: Beverly Hills/Pine Ridge Florida
I think there were 17 clips...each riveted to the underbody like the trans tunnel insulation clips. My 69 a late August, 69 car, didn't have the clips...so I figured no insulation. Best advice I can give is IF you want to use the mats, check the underbody and re-rivet each clip. The mats are big..about 3 foot x 2 foot...foil covered...yellow inside...about 3/4 inch thick. They go on the flat portion of the underbody, under the seats, then "fold" up over the front of the trans/bellhousing area. It's really a pretty ugly arrangement I could never find them in the AIM either. Chuck
I could never find them in the AIM either. Chuck
Safety Car
Joined: Jul 2001
Posts: 4,456
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From: Spicewood, Texas, USA TX-Texas
Easy Mike, If your AIM has UPC and sheet numbers, post back the location of the insulation shields for Smoke. It may be the same or close for 69.
Even if the shields were discontinued in the 69 model year, the sheets should still be in the AIM, but stamped "CANCELED", unless of course, they were manually removed before reproduction.
Even if the shields were discontinued in the 69 model year, the sheets should still be in the AIM, but stamped "CANCELED", unless of course, they were manually removed before reproduction.
Safety Car
Joined: Jul 2001
Posts: 4,456
Likes: 6
From: Spicewood, Texas, USA TX-Texas
SVM, that insulator is different than the ones Smoke is talking about. The transmission tunnel insulator was used from 63-75. The shields Smoke is talking about were only used 68 and part of 69. Since your car was an late 69 (after Chuck's), yours most likely did not have the floorboard shields.
Le Mans Master
Joined: Sep 2000
Posts: 5,635
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From: Orlando Floriduh
O.K. Thanks... I do have insulation under the carpet too. I am pretty sure it is original. What do you guys think?? From a thread on the NCRS board I believe that my carpet is original. I got the car with 87K on it last year. Two weeks later the odometer quit.
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Thread Starter
Le Mans Master
Joined: Aug 2000
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From: Semper ubi, sub ubi
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Thanks to all you guys for posting, I've ordered the replacement parts from Gary Gruhala, and just want to try and get them back in the right location. Easy Mike, if you have anyway of scanning the page from the 68 AIM, I'd sure be interested in looking at it.
My car is an early 69 car and I've found several things that I can't find in the AIM for 69. Maybe I should get a 68 AIM.
My car is an early 69 car and I've found several things that I can't find in the AIM for 69. Maybe I should get a 68 AIM.
Safety Car
Joined: Jul 2001
Posts: 4,456
Likes: 6
From: Spicewood, Texas, USA TX-Texas
SVM, I can't help much on the carpet. My 70 did not have the original carpet in the front, and the 70-72 judging manual is not much help even for 70, and I believe 68-69 carpet is different.
I know there are manufacturer's tags and binding clues, but that is about it. If no one comes up with and answer, try your question again next week; we should have some more 68-69 help by then.
I know there are manufacturer's tags and binding clues, but that is about it. If no one comes up with and answer, try your question again next week; we should have some more 68-69 help by then.
Race Director
Joined: Feb 1999
Posts: 16,978
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From: In Dreams There Is Truth Ohio
My 68 has the clips and the factory insulation. I was fortunate that when I went to the dealer in '75, the stuff was still available. I have not installed the insulation, no need to the sidemount headers don't transfer the heat to the floor boards. The clips are still in place.
Safety Car
Joined: Jan 2001
Posts: 3,637
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From: Norwalk Ct
I am doing the very same thing on my 69 as we speak.
I have just cleaned up all the underside and my riveted clips are all there.I have the new foil/fiberglass insulation and the metal plated that go over them.
I will take a picture later and send it to you...let me know what measurements you need.
Nick
I have just cleaned up all the underside and my riveted clips are all there.I have the new foil/fiberglass insulation and the metal plated that go over them.
I will take a picture later and send it to you...let me know what measurements you need.
Nick
Thread Starter
Le Mans Master
Joined: Aug 2000
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From: Semper ubi, sub ubi
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68Rdstr,
I think that like so many items on the 68 and early 69 models, it was something that was added at sometime in the 68 model year and removed midway through the long 69 model year.
I have found some really strange things on my car that don't seem to match what the AIM has for 69. I don't think that all of them are the results of "Bubba" modifications.
I think that like so many items on the 68 and early 69 models, it was something that was added at sometime in the 68 model year and removed midway through the long 69 model year.
I have found some really strange things on my car that don't seem to match what the AIM has for 69. I don't think that all of them are the results of "Bubba" modifications.
Le Mans Master
Joined: Jul 1999
Posts: 7,072
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From: Maryland
The original manufacturer of the carpet in '70 was J.P Stevens. They had paper tags stuck to the underside of the OEM carpeting along with a date code. My rear carpet on my '70 is original and I found the tags. I'm not sure if the same supplier was used in 68/69, but if you do find any of these paper tags (glued on to the backside) you can probably be assured it is original. FWIW my front carpets had been replaced on a 44k mile car. 
I think I've got a pic around here somewhere of the tag.... 
Holler if you want to see it and I'll dig it out & scan it for you. ~Juliet
I think I've got a pic around here somewhere of the tag.... Holler if you want to see it and I'll dig it out & scan it for you. ~Juliet
Team Owner
Joined: Jun 2000
Posts: 38,923
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From: Southbound
Cruise-In II Veteran
Part of our confusion is due to the changing nature of the AIMs. As running changes were incorporated, old AIM pages were supposed to be deleted and new (revised) pages put in. There were several work stations through out the plant which were suposed to always have an updated and correct AIM available. We must also consider the origin of the AIMs we have available to us since GM never intended them for publication. Are the current reprints early AIMs, late AIMs, incomplete AIMs? Who knows? Tis a puzzle.
Melting Slicks
Joined: Apr 1999
Posts: 2,675
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From: Sudbury MA
Re: (68rdstr)
68 rdstr,
Noticed that you have the same engine and trans with 4speed as I do in my 68 coupe. Curious what your engine suffix is, HP or HT.
Also, do your plastic front grilles have the silver edges on the horizontal bars or are they solid black with no silver.
Nice picture of your chassis with engine and transmission.
Noticed that you have the same engine and trans with 4speed as I do in my 68 coupe. Curious what your engine suffix is, HP or HT.
Also, do your plastic front grilles have the silver edges on the horizontal bars or are they solid black with no silver.
Nice picture of your chassis with engine and transmission.
Cruising
Joined: Aug 2001
Posts: 14
Likes: 0
Re: (Smokehouse69Mark2)
The version of the 68 AIM that I have has little or nothing about the retaining clips and underbody insulation. There is a reference to the underbody splash shields on the "insulator-plenum panel page" on UPC 1 ASM Sheet D9. It has to do with Dash Mat, Insulators & Splash Shield. I don't have a 69 AIM but something like that or additional info should be in the same "vicinity".
This is something where not enough information could create a problem since these are items that either weren't present on early 68 Corvettes or went through so many running changes over the 68-69 two year period. The 68 coupe that I have has a December build date and shows virtually no signs of ever having the underbody insulator mats, the underbody splash shields, the retaining clips, or the bolt stubs to hold the shields in place. In fact, my floor and toe pan have never been drilled where the rivets were supposed to hold these underbody splash shield bolt stubs or the underbody insulator mat retaining clips.
Also, the 68-69 NCRS Judging Manual does mention some fairly good reference information about the running changes. But it doesn't mention the retaining clips and I doubt that it would since it would require the disassembly or removal of the underbody splash shields to view or inspect them. TBarr
This is something where not enough information could create a problem since these are items that either weren't present on early 68 Corvettes or went through so many running changes over the 68-69 two year period. The 68 coupe that I have has a December build date and shows virtually no signs of ever having the underbody insulator mats, the underbody splash shields, the retaining clips, or the bolt stubs to hold the shields in place. In fact, my floor and toe pan have never been drilled where the rivets were supposed to hold these underbody splash shield bolt stubs or the underbody insulator mat retaining clips.
Also, the 68-69 NCRS Judging Manual does mention some fairly good reference information about the running changes. But it doesn't mention the retaining clips and I doubt that it would since it would require the disassembly or removal of the underbody splash shields to view or inspect them. TBarr