Author Topic: Underlayment differential area Fastback 67  (Read 1639 times)

Offline Fastback2013

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Underlayment differential area Fastback 67
« on: November 23, 2014, 11:25:47 AM »
I need some help with the correct dimensions for the underlayment on my fastback 67 (SJ).
When I removed the rear folddown seat there wasn't any underlayment (see picture 1)
I want to place the new underlayment above the differential area, but I do not have any reference for the right place and dimensions.
In the Osborn manuals, there isn't any drawing/explanation that the underlayment above the differential must be placed?
In picture 2 I have placed the new underlayment, but is it so that the outer lips must lay above the attaching points for the folddown seat or not?
If so, then the dimensions off the aftermarket piece isn't correct, therefore I hope that some one is able to give me the correct dimensions.
Last question, is what about the 2 hooks (where the seat is hooked back).
Is there a cut out necessary in the underlayment?
If some one has pictures, that is also very helpfull.
Thanks in advance for your help and answers,
Kind regards,
Jeroen
San Jose 7R02C1708xx
Fastback GTA
built on 01/12/1967

Offline J_Speegle

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Re: Underlayment differential area Fastback 67
« Reply #1 on: November 23, 2014, 01:52:34 PM »
- Looked through my pictures and though there are not all of pictures showing this area of the car half way disassembled could not find any with underlayment or signs they ever had any.

- Don't recall ever finding any there - likely just one more thing that contributed to the noisy properties of the fastbacks

- Not a surprise to me that a so called reproduction isn't exactly shaped the same way or covers the same exact area. Not unusual in some cases for the maker to "improve"  a new part.

- Yes adding 1/2" or so padding would create some additional challenges to hooking the rear seat in place unless the opening was well trimmed around where the attachment point would be
Jeff Speegle

Anything worth doing is worth doing concours ;)

Offline Bob Gaines

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Re: Underlayment differential area Fastback 67
« Reply #2 on: November 23, 2014, 04:06:17 PM »
- Looked through my pictures and though there are not all of pictures showing this area of the car half way disassembled could not find any with underlayment or signs they ever had any.

-
- Not a surprise to me that a so called reproduction isn't exactly shaped the same way or covers the same exact area. Not unusual in some cases for the maker to "improve"  a new part.

- Yes adding 1/2" or so padding would create some additional challenges to hooking the rear seat in place unless the opening was well trimmed around where the attachment point would be
+1
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline Fastback2013

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Re: Underlayment differential area Fastback 67
« Reply #3 on: November 24, 2014, 03:29:03 AM »
Thanks Jeff and Bob.
It is a bit odd that the aftermarket suppliers bring those things 'just like the originals', knowing that they weren't there in the first place...
Kind regards,
Jeroen
San Jose 7R02C1708xx
Fastback GTA
built on 01/12/1967

Offline TLea

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Re: Underlayment differential area Fastback 67
« Reply #4 on: November 24, 2014, 09:52:55 AM »
Thanks Jeff and Bob.
It is a bit odd that the aftermarket suppliers bring those things 'just like the originals', knowing that they weren't there in the first place...
Kind regards,
Jeroen
Well they kind of were. I find them in coupes and convertibles
Tim Lea  Shelby concours judge MCA, SAAC, Mid America

Offline Fastback2013

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Re: Underlayment differential area Fastback 67
« Reply #5 on: November 24, 2014, 11:28:18 AM »
So they put them down in coupes and convertibles, but not in Fastbacks?
Was/is there any (logic) explanation for?
Jeroen
San Jose 7R02C1708xx
Fastback GTA
built on 01/12/1967

Offline J_Speegle

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Re: Underlayment differential area Fastback 67
« Reply #6 on: November 24, 2014, 04:43:46 PM »
So they put them down in coupes and convertibles, but not in Fastbacks?
Was/is there any (logic) explanation for?

Hard to put ourselves in the mind of an engineer(s) almost 50 years ago. Might have been a cost saving thing or a clearance issue between the fold down panels and the top of the rear end floor panel rise.

IMHO not my job ;) to understand why - just if it was done and to reproduce the look if it was or was not.
Jeff Speegle

Anything worth doing is worth doing concours ;)