Transmission tunnel insulation installation
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 878
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From: Minneapolis, MN USA
Transmission tunnel insulation installation
Hi all - I purchased a new insulation piece for the transmission tunnel since my transmission is out. The existing (old) insulation seems to be all fiberglass with some foil backing. It is held in place by the sharp clips that puncture through the insulation and then you fold the tab over to hold it in place. However, the new insulation piece is significantly stiffer...I don't think I will be able to get those old tabs to puncture through this harder material without breaking. Does anyone have any ideas/suggestions about how to install this? Also, I notice you need to remove the shifter to really put this in place properly. That is to hard for me...any big reason why I can't cut a slot in the end facing the rear of the car so that it can wrap around the shifter? obviously I will lose a little insulation in that space...but oh well. any other ideas?
Just another Corvette guy
Joined: Feb 1999
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From: Palm Springs, CA.
I have installed these in cars with the transmission and shifter in place by slitting it all the way down the center, from front to rear. Then placing each piece in from the side until they touch together at the top. Makes for a much easier install and the noise reduction/heat barrier abilities are not diminished at all. If you need to, try puncturing the holes for your bendable tabs before you install. Just hold them up in place, feel for the tab and mark the spot. Then lower and puncture it. It's only insulation so it's forgivable if your hole is not exact.
Cheers, Greg
Cheers, Greg
Race Director
Joined: Apr 2011
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From: North of Toronto - Ontario
My (automatic) was in place but I had the shifter cable speedo cables disconnected and managed to sort of rotate the insulation into place with much cursing and swearing. (The next winter I had the transmission out and it would have been much easier)
The new insulation was still tin-foil sandwiching a fiberglass core but it pushed onto the retaining tabs without issue, maybe try pushing a pointed screwdriver through a corner somewhere to test yours
One thing to keep in mind is that the insulating qualities are mainly dependent on the airspace in the core so try to not crush it (as much as you can) and although argued, I maintain the foam horse collar at the front helps keep a lot of the heat from getting in there in the first place
M
The new insulation was still tin-foil sandwiching a fiberglass core but it pushed onto the retaining tabs without issue, maybe try pushing a pointed screwdriver through a corner somewhere to test yours
One thing to keep in mind is that the insulating qualities are mainly dependent on the airspace in the core so try to not crush it (as much as you can) and although argued, I maintain the foam horse collar at the front helps keep a lot of the heat from getting in there in the first place
M
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 878
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From: Minneapolis, MN USA
Thanks guys.. The core is quite solid, but I like the suggestion of trying to pre-puncture it where the tabs are. I also purchased the foam collar. Does that get glued or something? There is no adhesive strip on it... Or do I just wedge it in after I have the motor and trans back in place?
Is my vette stock?? HAHA
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Some of my tabs were broken off so I used a thin machine bolt and Fender washers. They work great but far from the factory look
Race Director
Joined: Apr 2011
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From: North of Toronto - Ontario
BTW, before you put the insulation have a look at the rubber shifter seal boot to make sure it's not torn
M
Last edited by Mooser; Jun 26, 2020 at 10:13 AM.
Safety Car
Joined: May 2008
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From: Lafayette Louisiana
ditto here, too.
ditto here too, much easier to install than the tabs that bend over. and same here, I put 3 or 4 globs of GOOP on the foam collar to hold in place.
Also there are many posts on the heat in the cockpit issue. Really best to try to seal up every thing and replace all the rubber seals to make a significant difference.
Last edited by 20mercury; Jun 26, 2020 at 11:33 AM.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
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i just stuffed the foam collar in there and it stays put. Comes out easy when I ull the engine, and it doesnt get ruined. Hopefully the engine can stay put this winter...first time in 4 years....but while in there......
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Race Director
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From: North of Toronto - Ontario
The collar is all for keeping the engine compartment heat out of the tunnel and IMHO the insulation as well since it's not really over the exhaust pipes when they are under there
M
M
Is my vette stock?? HAHA
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I would think the heat from the headers would travel past the engine 8nto the tunnel. I have the collar, the shield and thick matting under my carpet. My feet never got hot
with the ramshorns and 69 style pipes but there is a slight temp increase with the headers and same pipes. I bet it would be less with dynomat or something similar
with the ramshorns and 69 style pipes but there is a slight temp increase with the headers and same pipes. I bet it would be less with dynomat or something similar
Team Owner
Joined: Jan 2006
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From: Crossville TN
The problem with putting adhesive on the trans or on the collar (when trans is already assembled to the car) is that it will get all smeared around as you fiddle with getting it in place. The factory used no adhesive. Installing that collar (without tearing it up) will be enough "fun", without any adhesive.