Do Tunnel Plates Really Make a Difference?
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 3,475
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From: Wake Forest NC
Do Tunnel Plates Really Make a Difference?
Caught this post about tunnel plates in another thread, (thanks, RedZMonte,) and am wondering, do they really affect handling enough to notice?
I have C6Z51 sways and Bilstein HD shocks. My tuner mentioned adding a tunnel plate.
What has been your experience with tunnel plates?
UPDATE 11/14/13: Tell us what suspension upgrades you made before adding the tunnel plate.
.
I have C6Z51 sways and Bilstein HD shocks. My tuner mentioned adding a tunnel plate.
What has been your experience with tunnel plates?
UPDATE 11/14/13: Tell us what suspension upgrades you made before adding the tunnel plate.
.
Last edited by s'noJob; Nov 14, 2013 at 06:25 PM. Reason: update
Safety Car
Joined: Jan 2001
Posts: 4,387
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From: Boise ID
When I added headers to my 2000 FRC I also added a 1/4 inch ceramic coated tunnel plate. I thought there was a noticeable difference in the feel of the car (while cornering) and it used to moan when driving over wide speed bumps but, not afterwards. Also did not feel any extra heat after the header install.
Team Owner
Joined: May 2003
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From: East Meadow NY
St. Jude Donor '12
When I added headers to my 2000 FRC I also added a 1/4 inch ceramic coated tunnel plate. I thought there was a noticeable difference in the feel of the car (while cornering) and it used to moan when driving over wide speed bumps but, not afterwards. Also did not feel any extra heat after the header install.
I added the tunnel plate to my vert when all of the work was done to it. There was some reduced flex when going into and out of my driveway and other turns like it. There was a significant reduction in the console temperature.
Safety Car
Joined: Nov 2013
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From: Ex DPRK, now just N of Medford, OR
Added an aftermarket plate, instant reduction in cowl shake! Whole car feels more solid, less overall vibration on the road. I'd say it should be the first mod, and a good opportunity to add extra heat insulation inside the backbone.
Safety Car
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From: Fords, NJ
Race Director
Joined: Apr 2007
Posts: 11,152
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From: South Western Ontario
I installed a 1/4" plate when the car was apart. I got it for $100 so not a big expense. But, I didn't think it did a whole lot. To me, it was certainly not a massive improvement like I've read in some posts.
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From: Anthony TX
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St. Jude Donor '08
Same for me.
I have a ZO6 and they are a little stiffer car to begin with.
Didnt really notice all that much difference.
Yes there was a little more heat reduction.
BC
I have a ZO6 and they are a little stiffer car to begin with.
Didnt really notice all that much difference.
Yes there was a little more heat reduction.
BC
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 3,475
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From: Wake Forest NC
Well, so far the results seem mixed. Some of you felt improvement, some not so much.
I imagine it might depend on what you have on the car to begin with. A C5 with heavy suspension mods or a base Z06 or Z51 might not notice the difference as much as a bone-stock coupe or vert after acquiring a new tunnel plate. That's why I mentioned my C6Z51 sway bars and Bilstein shocks. It would be interesting to know what owners already had on their car before the plate upgrade.
Still, as NukeC5 pointed out, they made them thicker for a reason - it would seem that any improvement, whether noticeable or not, is still an improvement. A chassis that is 4% stiffer, let's say, is still stiffer and will help stabilize the car better.
One constant I noticed was the heat resistance. I don't have headers, but if I ever do plan on getting them, it sounds like I should get a plate with the insulation.
.
I imagine it might depend on what you have on the car to begin with. A C5 with heavy suspension mods or a base Z06 or Z51 might not notice the difference as much as a bone-stock coupe or vert after acquiring a new tunnel plate. That's why I mentioned my C6Z51 sway bars and Bilstein shocks. It would be interesting to know what owners already had on their car before the plate upgrade.
Still, as NukeC5 pointed out, they made them thicker for a reason - it would seem that any improvement, whether noticeable or not, is still an improvement. A chassis that is 4% stiffer, let's say, is still stiffer and will help stabilize the car better.
One constant I noticed was the heat resistance. I don't have headers, but if I ever do plan on getting them, it sounds like I should get a plate with the insulation.
.
Melting Slicks
Joined: Jun 2012
Posts: 3,163
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From: Oceanside California
Well, so far the results seem mixed. Some of you felt improvement, some not so much.
I imagine it might depend on what you have on the car to begin with. A C5 with heavy suspension mods or a base Z06 or Z51 might not notice the difference as much as a bone-stock coupe or vert after acquiring a new tunnel plate. That's why I mentioned my C6Z51 sway bars and Bilstein shocks. It would be interesting to know what owners already had on their car before the plate upgrade.
Still, as NukeC5 pointed out, they made them thicker for a reason - it would seem that any improvement, whether noticeable or not, is still an improvement. A chassis that is 4% stiffer, let's say, is still stiffer and will help stabilize the car better.
One constant I noticed was the heat resistance. I don't have headers, but if I ever do plan on getting them, it sounds like I should get a plate with the insulation.
.
I imagine it might depend on what you have on the car to begin with. A C5 with heavy suspension mods or a base Z06 or Z51 might not notice the difference as much as a bone-stock coupe or vert after acquiring a new tunnel plate. That's why I mentioned my C6Z51 sway bars and Bilstein shocks. It would be interesting to know what owners already had on their car before the plate upgrade.
Still, as NukeC5 pointed out, they made them thicker for a reason - it would seem that any improvement, whether noticeable or not, is still an improvement. A chassis that is 4% stiffer, let's say, is still stiffer and will help stabilize the car better.
One constant I noticed was the heat resistance. I don't have headers, but if I ever do plan on getting them, it sounds like I should get a plate with the insulation.
.
Race Director
Joined: Apr 2010
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From: Arizona
Got mine from TPS Motorsports. 1/4" and while the material is stronger, I am not so sure it made a difference I can actually feel. But, I am certain the 1/4" thickness serves a purpose over the flimsy stock tunnel plate.
Also, got a respectable discount as a Forum member as well.
Also, got a respectable discount as a Forum member as well.
Thread Starter
Melting Slicks
Joined: Nov 2007
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From: Wake Forest NC
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Well, so far the results seem mixed. Some of you felt improvement, some not so much.
I imagine it might depend on what you have on the car to begin with. A C5 with heavy suspension mods or a base Z06 or Z51 might not notice the difference as much as a bone-stock coupe or vert after acquiring a new tunnel plate. That's why I mentioned my C6Z51 sway bars and Bilstein shocks. It would be interesting to know what owners already had on their car before the plate upgrade.
Still, as NukeC5 pointed out, they made them thicker for a reason - it would seem that any improvement, whether noticeable or not, is still an improvement. A chassis that is 4% stiffer, let's say, is still stiffer and will help stabilize the car better.
One constant I noticed was the heat resistance. I don't have headers, but if I ever do plan on getting them, it sounds like I should get a plate with the insulation.
.
I imagine it might depend on what you have on the car to begin with. A C5 with heavy suspension mods or a base Z06 or Z51 might not notice the difference as much as a bone-stock coupe or vert after acquiring a new tunnel plate. That's why I mentioned my C6Z51 sway bars and Bilstein shocks. It would be interesting to know what owners already had on their car before the plate upgrade.
Still, as NukeC5 pointed out, they made them thicker for a reason - it would seem that any improvement, whether noticeable or not, is still an improvement. A chassis that is 4% stiffer, let's say, is still stiffer and will help stabilize the car better.
One constant I noticed was the heat resistance. I don't have headers, but if I ever do plan on getting them, it sounds like I should get a plate with the insulation.
.
A number of years ago, when C5s were still being manufactured, and aftermarket tunnel plates were all the rage, I recall seeing a few posts from people going this route.
Many stock plates get trashed when people buy the thicker plates and then have no use for their old one. Salvage yards also sell them of course too, so they're generally pretty cheap. Maybe even combine a C6 and a stock C5 plate.
Even if going this route, I would still recommend the heat insulation, such as Elite's Thermal Abs, or Thermo-Tec's product etc. Even when used on stock plates, the heat reduction is significant.
HTH
Race Director
Joined: Apr 2007
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From: South Western Ontario
Also, I don't think a 1/4" or 3/8" thick Al plate will be much if any lighter then the stock plate.
Thread Starter
Melting Slicks
Joined: Nov 2007
Posts: 3,475
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From: Wake Forest NC
And by lightness, I was referring to the practice of mounting double steel stock plates. A 1/4 inch Al plate would be lighter than two 1/8 inch steel plates.
.
Team Owner
Joined: May 2001
Posts: 87,361
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From: Western NY
When I said it wouldn't make a structural difference, I meant between a base and an upgraded car. The plate would add 4%, let's say, more structural stiffness to both vehicles. But that 4% may seem more apparent on a base vehicle than on one that is already say 25% stiffer than the base.
And by lightness, I was referring to the practice of mounting double steel stock plates. A 1/4 inch Al plate would be lighter than two 1/8 inch steel plates.
.
And by lightness, I was referring to the practice of mounting double steel stock plates. A 1/4 inch Al plate would be lighter than two 1/8 inch steel plates.
.
Having said that, I have an '01 coupe, with the selective suspension, and added one of those tunnel plates to it a LONG time ago. I really don't remember if I noticed any difference in stiffness, but from an engineering standpoint it makes sense....
Melting Slicks
Joined: Feb 2001
Posts: 2,804
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From: Northville, MI
When you look at the structural rigidity of the cars, the vert was somewhere at 22, the coupe at 24 and the FRC was close to 26, according to GM. With that in mind, you might find some additional rotational stiffness to the vert, minimal to the coupe and negligible to the FRC. As I recall, the tunnel plate was originally to keep the road debris from the exhaust and undercarriage.