Tunnel plate replacement
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Advanced
Joined: Jun 2007
Posts: 75
Likes: 0
From: Winfield Illinois
Tunnel plate replacement
Ordered a tunnel plate and thermal blanket from Elite Engineering which should come later today.
Checking with anyone who has replaced their tunnel plate as to any problems they had getting the original one off.
I looked at the installation instructions online and they caution about using too much torque when installing the new one or else you risk breaking off the head of the bolt.
So I was wondering if anyone had any difficulty getting the bolts off without breaking off the head.
I hope to get use of a 4 post lift which should make access a little easier.
Checking with anyone who has replaced their tunnel plate as to any problems they had getting the original one off.
I looked at the installation instructions online and they caution about using too much torque when installing the new one or else you risk breaking off the head of the bolt.
So I was wondering if anyone had any difficulty getting the bolts off without breaking off the head.
I hope to get use of a 4 post lift which should make access a little easier.
Burning Brakes
Joined: Jan 2007
Posts: 1,152
Likes: 3
From: Hawaii
Someone gave me a stock tunnel plate. I sandwiched a thermal blanket between it and the original. A little WD40 eased the removal of the original bolts. (a LOT of them!) A little modification was needed to get the two to mate. On the re-install I had to use slightly longer bolts. I choose grade 8. No problems.
I'm sure not as effective as what you bought, but I'm a cheap a$$. Is there a difference? I dunno. Has to be a smidge better than what was there and aside from the cost of the blanket ($26) it has to be better than stock.
I'm sure not as effective as what you bought, but I'm a cheap a$$. Is there a difference? I dunno. Has to be a smidge better than what was there and aside from the cost of the blanket ($26) it has to be better than stock.
Safety Car
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From: This is not a Song, It's an Outburst: Or, The Establishment Blues; Sixto Diaz Rodriguez
^ ^ 
You must be an engineer. That's a pretty good idea, and like you've said, lot's cheaper. A decent, heavy duty plate will set you back at least $200. and that's if you install yourself. 
You must be an engineer. That's a pretty good idea, and like you've said, lot's cheaper. A decent, heavy duty plate will set you back at least $200. and that's if you install yourself.
Melting Slicks
Joined: Oct 2007
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From: It's true money can't buy happiness, but it is more comfortable crying in a Corvette than on a bicyc
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36 bolts if I remember. I used a speed wrench and a cordless drill with a 1/4" socket adapter. I have an air rachet but it was slooow. Bolts came off easy. No need for different bolts, plenty long.
You will notice cooler temps in the console area.
You will notice cooler temps in the console area.
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Funny you bring it up because I just installed my thermal tunnel plate yesterday when I intalled my Corsa X-pipe, Callaway Honker CAI and Koni FSD shocks.
What I was suprised about was how thin and wobbly the OEM tunnel plate is. You can literally twist it compared to the Elite Engineering Thermal Tunnel plate.
In terms of issues, the only one I had was that some of the OEM bolts were not exactly fitted correctly during the assembly line process so I had to replace them with new bolts. We also applied extra material, similar to the thermal abs on the tunnel plate on the sides of the exhaust shaft to further insulate the area.
I haven't had a chance to really have fun with the car and test out the mods yet as I was stuck in heavy evening rush hour traffic on the drive home from the shop.
What I was suprised about was how thin and wobbly the OEM tunnel plate is. You can literally twist it compared to the Elite Engineering Thermal Tunnel plate.
In terms of issues, the only one I had was that some of the OEM bolts were not exactly fitted correctly during the assembly line process so I had to replace them with new bolts. We also applied extra material, similar to the thermal abs on the tunnel plate on the sides of the exhaust shaft to further insulate the area.
I haven't had a chance to really have fun with the car and test out the mods yet as I was stuck in heavy evening rush hour traffic on the drive home from the shop.
Last edited by MSG C5; May 3, 2012 at 07:31 PM.
Racer
Joined: Jan 2007
Posts: 282
Likes: 0
From: Machesney Park Illinois
I put the 3/8 elite tunnel plate on mine. There was a lot less heat transmitted to the counsel. Ii also stiffened the car quite a bit. It was easy to install, did mine on ramps and jack stands in 2 hours
Pro
Joined: Mar 2004
Posts: 607
Likes: 9
From: Sandy Eggo, California
No problem getting the stock plate off. I used Rhino ramps. You may have some trouble removing the two O2 sensors from the H pipe. Also you'll need to remove the bolts from the front flanges that attach the H pipe to the header pipes. Then lower lower the H pipe to gain access to the tunnel plate. I did purchase a 1/4" torque wrench to install the new plate to specs. I believe the torque was 89 inch pounds or 7.5 foot pounds for the 36 bolts. I didn't want to take the chance of breaking off one of the bolt heads during the install. I must have had a senior moment because I installed the new plate with the insulated side facing up. It didn't look right to me so I called Elite Engineering and they told me I had installed the plate upside down. The insulated side faces down.
Advanced
Joined: Nov 2011
Posts: 93
Likes: 0
From: Myrtle Beach South Carolina
Someone gave me a stock tunnel plate. I sandwiched a thermal blanket between it and the original. A little WD40 eased the removal of the original bolts. (a LOT of them!) A little modification was needed to get the two to mate. On the re-install I had to use slightly longer bolts. I choose grade 8. No problems.
I'm sure not as effective as what you bought, but I'm a cheap a$$. Is there a difference? I dunno. Has to be a smidge better than what was there and aside from the cost of the blanket ($26) it has to be better than stock.
I'm sure not as effective as what you bought, but I'm a cheap a$$. Is there a difference? I dunno. Has to be a smidge better than what was there and aside from the cost of the blanket ($26) it has to be better than stock.
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Pro
Joined: Mar 2004
Posts: 607
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From: Sandy Eggo, California
One more thing that may be helpful to you. The stock tunnel plate has one hole that's smaller in diameter than all the other holes. I think it's about the 5th hole back from the front, on the driver's side. The instructions on the new plate said to use that smaller hole as a reference guide, and install the one smaller hole that's on the new tunnel plate at the exact same location. Well when I did that, it put the insulated side facing up on my new plate. So, I don't take all the blame for installing it upside down. When I called Elite they told me that the insulation pad had apparently been glued onto the wrong side of the new plate at the factory. The tech told me to go ahead and bolt the smaller hole, that was originally on the driver's side, onto the passenger's side, and the new plate would still function the same installed that way. This put the insulated side facing down and in the correct position. The people at Elite were great about the mix up. They sent me a set of Fat Daddy frame savers for my trouble.
Burning Brakes
Joined: Feb 2007
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From: Vancouver B.C.
Installed the plate without the thermal blanket; the main benefit for me was stiffening the chassis although there is some heat reduction.
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Good info for those looking to change the tunnel plates. Thanks for posting up what you did.
Drifting
Joined: Mar 2011
Posts: 1,807
Likes: 331
From: Ocala FL
Someone gave me a stock tunnel plate. I sandwiched a thermal blanket between it and the original. A little WD40 eased the removal of the original bolts. (a LOT of them!) A little modification was needed to get the two to mate. On the re-install I had to use slightly longer bolts. I choose grade 8. No problems.
I'm sure not as effective as what you bought, but I'm a cheap a$$. Is there a difference? I dunno. Has to be a smidge better than what was there and aside from the cost of the blanket ($26) it has to be better than stock.
I'm sure not as effective as what you bought, but I'm a cheap a$$. Is there a difference? I dunno. Has to be a smidge better than what was there and aside from the cost of the blanket ($26) it has to be better than stock.
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
I thought about this but I don't want to get involved with taking the exhaust system down. Plus my 3" X pipe already required holes to be drilled in the oem plate for the 02 sensors. I would hate to deal with drilling even thicker plating.
Racer
Joined: Oct 2004
Posts: 432
Likes: 49
From: Southern Maryland
Ordered a tunnel plate and thermal blanket from Elite Engineering which should come later today.
Checking with anyone who has replaced their tunnel plate as to any problems they had getting the original one off.
I looked at the installation instructions online and they caution about using too much torque when installing the new one or else you risk breaking off the head of the bolt.
So I was wondering if anyone had any difficulty getting the bolts off without breaking off the head.
I hope to get use of a 4 post lift which should make access a little easier.
Checking with anyone who has replaced their tunnel plate as to any problems they had getting the original one off.
I looked at the installation instructions online and they caution about using too much torque when installing the new one or else you risk breaking off the head of the bolt.
So I was wondering if anyone had any difficulty getting the bolts off without breaking off the head.
I hope to get use of a 4 post lift which should make access a little easier.
