Lost part of my air dam
08-26-2018, 07:36 PM
#21
E-Ray, 3LZ, ZER, LIFT
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Strange I have ~40 Vette PDFs and first anyone had that happen. I click on them to copy the URL and never had that message. They come directly from my website that gets thousands of visits each day.
08-26-2018, 10:10 PM
#22
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St. Jude Donor '13
I was hoping the block was a one time glitch, but no.
I can click on the link normally, but when I ask to open the file I get that warning and block.
Is that same compilation posted somewhere else?
I can click on the link normally, but when I ask to open the file I get that warning and block.
Is that same compilation posted somewhere else?
08-26-2018, 11:07 PM
#23
E-Ray, 3LZ, ZER, LIFT
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08-27-2018, 10:03 AM
#24
Instructor
I replace mine after running over a mean old alligator(Tractor tire treads). Replace the the passenger side air dam and the center one, plus the passenger side wheel well. My 85 Trans am wouldn't run on the highway with out at least the center air dam. Since the TA doesn't have a grill the air passes up from underneath.
08-27-2018, 04:59 PM
#25
bimmerborn, and jerryu,
Thanks too, (all) for the replies and additional information, photos and graphics.
My C7 isn't going to be driven over 75 to 80 mph, so the racing aspects of air-damming to me, aren't of consequence. What is of interest are fuel economy AND engine cooling.
Keeping air-damming in place for engine cooling and fuel economy on my non-Z51 is of high importance to me. Accordingly, learning how to DIY replace damaged air-damming is something that I want to know how to do!
08-27-2018, 08:31 PM
#26
E-Ray, 3LZ, ZER, LIFT
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^^
It will have a small mpg improvement at highway speeds but no quantifiable data. However unlike some prior Vettes that were called “bottom breathers” the C7 gets all it‘s cooling air from the grill.
It all goes through the radiator and the upper 1/3 of that exits though the hood vent. The remainder exits through the side vents and open areas next to the engine.
It will have a small mpg improvement at highway speeds but no quantifiable data. However unlike some prior Vettes that were called “bottom breathers” the C7 gets all it‘s cooling air from the grill.
It all goes through the radiator and the upper 1/3 of that exits though the hood vent. The remainder exits through the side vents and open areas next to the engine.
Last edited by JerryU; 08-27-2018 at 09:35 PM.
08-27-2018, 09:09 PM
#27
My plastic air dams and screws are still in the back from when I bought the car last week. Dealer said most people don't want them on because they break off so easily. I thought about leaving them off but if there are key functional differences between not on and on then I'll screw them on tomorrow.
08-27-2018, 09:22 PM
#28
Just took a look at the operation and damn these cars are low. I don't have a jack and I can't get enough room to make it happen. I'll have to take it to the local dealer and have them put them on. It sounds like a good idea if it aid's high speed wind flow and such.
08-27-2018, 09:33 PM
#29
E-Ray, 3LZ, ZER, LIFT
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^^
From the number of posts of the center air dams breaking, have to think GM made a change in materials. This is why:
My C6 Z51 had a center and side air dams. They scraped moderately every time I left my driveway. No big deal. About once a year I would sandpaper the lower edge. They looked fine and never broke or split.
The C6 air dams were somewhat lower than the C7 as evidenced by my C7 Z51 and my Grand Sport side air dams seldom scraping when I leave my driveway. If I pull out fast I will hear some modest sound. They are designed to bend so the material should be durable enough to do that without breaking unless you hit an 18 wheeler tire tread etc.
Just an observation.
From the number of posts of the center air dams breaking, have to think GM made a change in materials. This is why:
My C6 Z51 had a center and side air dams. They scraped moderately every time I left my driveway. No big deal. About once a year I would sandpaper the lower edge. They looked fine and never broke or split.
The C6 air dams were somewhat lower than the C7 as evidenced by my C7 Z51 and my Grand Sport side air dams seldom scraping when I leave my driveway. If I pull out fast I will hear some modest sound. They are designed to bend so the material should be durable enough to do that without breaking unless you hit an 18 wheeler tire tread etc.
Just an observation.
08-27-2018, 11:14 PM
#30
So I was able to get the right and left side air dam on but there are 4 holes for the bolts on the plastic dam but only 3 line up with the u-clips that are under the car. The two outboard ones line up and the one closest to the center line up but one of the middle ones does not. I have enough bolts for 4 per side and 6 for the center so am I missing something? They seem secure enough with just the 3 but I'm that guy. I could drill a hole in the plastic and make a new hole to line up with the 4th u-clip but I'd rather not if not needed.
08-28-2018, 10:52 AM
#31
Melting Slicks
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So I was able to get the right and left side air dam on but there are 4 holes for the bolts on the plastic dam but only 3 line up with the u-clips that are under the car. The two outboard ones line up and the one closest to the center line up but one of the middle ones does not. I have enough bolts for 4 per side and 6 for the center so am I missing something? They seem secure enough with just the 3 but I'm that guy. I could drill a hole in the plastic and make a new hole to line up with the 4th u-clip but I'd rather not if not needed.
Meanwhile, I find it very strange that the holes don't line up. Possibly the wrong part? Another oddity is that they left the air dams off. THOSE are the items that usually ARE put on. It's the front splitter and side skirts that they often leave off for fear of test drive maniacs and negligent employees damaging them.
You may want to try to find a list similar to what JerryU posted here (https://www.corvetteforum.com/forums...-breaking.html) in post #26. He shows the models of 2017/18 GS's that have the center air dams, and those that don't. Only the base GS without the stage 2 or 3 aero packages has the center air dam in those years. Maybe yours wasn't supposed to have one anyway?
Last edited by IAIA; 08-28-2018 at 11:14 AM.
08-28-2018, 10:54 AM
#32
Melting Slicks
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^^
From the number of posts of the center air dams breaking, have to think GM made a change in materials. This is why:
My C6 Z51 had a center and side air dams. They scraped moderately every time I left my driveway. No big deal. About once a year I would sandpaper the lower edge. They looked fine and never broke or split.
The C6 air dams were somewhat lower than the C7 as evidenced by my C7 Z51 and my Grand Sport side air dams seldom scraping when I leave my driveway. If I pull out fast I will hear some modest sound. They are designed to bend so the material should be durable enough to do that without breaking unless you hit an 18 wheeler tire tread etc.
Just an observation.
From the number of posts of the center air dams breaking, have to think GM made a change in materials. This is why:
My C6 Z51 had a center and side air dams. They scraped moderately every time I left my driveway. No big deal. About once a year I would sandpaper the lower edge. They looked fine and never broke or split.
The C6 air dams were somewhat lower than the C7 as evidenced by my C7 Z51 and my Grand Sport side air dams seldom scraping when I leave my driveway. If I pull out fast I will hear some modest sound. They are designed to bend so the material should be durable enough to do that without breaking unless you hit an 18 wheeler tire tread etc.
Just an observation.
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JerryU (08-28-2018)
08-28-2018, 01:17 PM
#33
Advanced
center air dam
[QUOTE=JerryU;1597875276]
^^
From the number of posts of the center air dams breaking, have to think GM made a change in materials. This is why:
My C6 Z51 had a center and side air dams. They scraped moderately every time I left my driveway. No big deal. About once a year I would sandpaper the lower edge. They looked fine and never broke or split.
The C6 air dams were somewhat lower than the C7 as evidenced by my C7 Z51 and my Grand Sport side air dams seldom scraping when I leave my driveway. If I pull out fast I will hear some modest sound. They are designed to bend so the material should be durable enough to do that without breaking unless you hit an 18 wheeler tire tread etc.
Just an observation.
I have a steep concrete driveway (7%) and the original center air dam tore after about a year. Replaced it with one from the dealer and it tore the first time down the driveway. The new one appeared to be slightly more flexible than the old. Tore it completely off since it didn't seem like a good idea to be dragging around the thing and have it eventually being debris on the highway. Not replacing it again. The tire dams get scraped, especially down the driveway. They are in poor shape and had to remount one of the clips on the right side as the dam was hanging a little low.
From the number of posts of the center air dams breaking, have to think GM made a change in materials. This is why:
My C6 Z51 had a center and side air dams. They scraped moderately every time I left my driveway. No big deal. About once a year I would sandpaper the lower edge. They looked fine and never broke or split.
The C6 air dams were somewhat lower than the C7 as evidenced by my C7 Z51 and my Grand Sport side air dams seldom scraping when I leave my driveway. If I pull out fast I will hear some modest sound. They are designed to bend so the material should be durable enough to do that without breaking unless you hit an 18 wheeler tire tread etc.
Just an observation.
Last edited by Rich0071; 08-28-2018 at 01:20 PM. Reason: correct spelling
08-28-2018, 01:45 PM
#34
Thanks for the tip. ^^^^
Thanks too, (all) for the replies and additional information, photos and graphics.
My C7 isn't going to be driven over 75 to 80 mph, so the racing aspects of air-damming to me, aren't of consequence. What is of interest are fuel economy AND engine cooling.
Keeping air-damming in place for engine cooling and fuel economy on my non-Z51 is of high importance to me. Accordingly, learning how to DIY replace damaged air-damming is something that I want to know how to do!
Thanks too, (all) for the replies and additional information, photos and graphics.
My C7 isn't going to be driven over 75 to 80 mph, so the racing aspects of air-damming to me, aren't of consequence. What is of interest are fuel economy AND engine cooling.
Keeping air-damming in place for engine cooling and fuel economy on my non-Z51 is of high importance to me. Accordingly, learning how to DIY replace damaged air-damming is something that I want to know how to do!
Last edited by bc928; 08-28-2018 at 01:45 PM.
08-28-2018, 01:58 PM
#35
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St. Jude Donor '13
A possible factor in some of the problems would be that no two Corvettes have the same ride height. Probably a combination of not being set accurately at the factory, and then settles a bit over the first 500-1,000 miles. Kinda like the alignment problems on new 'vettes.
The Service Manual has a chart showing the proper ride height and tolerances for all the different models of C7, C6 Manual was similar. The chart allows you to measure from the top of the wheel well arches to the pavement (new tires, full fuel, no people or luggage), or be more precise and measure some suspension points under the car but that method has its own difficulties.
Our 2017 Z51 was about 1/8" low in front and 3/8" low in the back, each turn of the adjustment bolts changes that corner by about 3/32" after you drive a couple of hundred miles to re-settle everything. In addition to scraping the side pieces more than our C6, our C7 actually had a high-centered scrape in the middle over some speed bumps in Phoenix, regardless of approach angle or speed. It took the dealer a couple of tries to get it right on spec, but I'm hopeful for this winter out west. Of course, I've got more miles on the tires now and that may cancel the benefit, but hopefully it's enough.
For aerodynamics, having the proper front-rear rake is important; you don't want your Corvette to try being an airplane. For front clearance, having the rear a bit too low in relation to the front will actually give a bit more front clearance because of the angle change. I go for the stock height and rake, hope for the best.
The Service Manual has a chart showing the proper ride height and tolerances for all the different models of C7, C6 Manual was similar. The chart allows you to measure from the top of the wheel well arches to the pavement (new tires, full fuel, no people or luggage), or be more precise and measure some suspension points under the car but that method has its own difficulties.
Our 2017 Z51 was about 1/8" low in front and 3/8" low in the back, each turn of the adjustment bolts changes that corner by about 3/32" after you drive a couple of hundred miles to re-settle everything. In addition to scraping the side pieces more than our C6, our C7 actually had a high-centered scrape in the middle over some speed bumps in Phoenix, regardless of approach angle or speed. It took the dealer a couple of tries to get it right on spec, but I'm hopeful for this winter out west. Of course, I've got more miles on the tires now and that may cancel the benefit, but hopefully it's enough.
For aerodynamics, having the proper front-rear rake is important; you don't want your Corvette to try being an airplane. For front clearance, having the rear a bit too low in relation to the front will actually give a bit more front clearance because of the angle change. I go for the stock height and rake, hope for the best.
08-28-2018, 02:53 PM
#36
Le Mans Master
it is a pos. mine ripped the first cpl weeks, i took it in and stealer says i hit something, crawled underneath it took the screws out, done.
GS don t have it, so i don t need it, specially to just tear again.
GS don t have it, so i don t need it, specially to just tear again.
08-28-2018, 04:30 PM
#37
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St. Jude Donor '13
So GM and JerryU's sources don't know what they're talking about, right?
GM just puts the air dam on your car because they want it to be a little heavier and cost a little more?
If you said "I never ever drive over 70 mph or corner hard at that speed, so I should be ok without it", that would be reasonable.
But to say that you don't need it because "GS don't have it", sounds silly.
GM just puts the air dam on your car because they want it to be a little heavier and cost a little more?
If you said "I never ever drive over 70 mph or corner hard at that speed, so I should be ok without it", that would be reasonable.
But to say that you don't need it because "GS don't have it", sounds silly.
08-28-2018, 05:07 PM
#38
The "center section" of my deflector on my '17 C7 Stingray, tore at the horizontal crease/seam after just 2,500 miles. I have searched for a better/upgraded aftermarket deflector, but have not found one. With so many owners who have had issues, why wouldn't there be a supplier who has made a replacement that is more durable?
08-28-2018, 05:33 PM
#39
You're calling it an air dam but as far as I know--mine, at least--is a rubber-type product, not plastic. The splitter, however, is more of a plastic-like product.
Meanwhile, I find it very strange that the holes don't line up. Possibly the wrong part? Another oddity is that they left the air dams off. THOSE are the items that usually ARE put on. It's the front splitter and side skirts that they often leave off for fear of test drive maniacs and negligent employees damaging them.
You may want to try to find a list similar to what JerryU posted here (https://www.corvetteforum.com/forums...-breaking.html) in post #26. He shows the models of 2017/18 GS's that have the center air dams, and those that don't. Only the base GS without the stage 2 or 3 aero packages has the center air dam in those years. Maybe yours wasn't supposed to have one anyway?
Meanwhile, I find it very strange that the holes don't line up. Possibly the wrong part? Another oddity is that they left the air dams off. THOSE are the items that usually ARE put on. It's the front splitter and side skirts that they often leave off for fear of test drive maniacs and negligent employees damaging them.
You may want to try to find a list similar to what JerryU posted here (https://www.corvetteforum.com/forums...-breaking.html) in post #26. He shows the models of 2017/18 GS's that have the center air dams, and those that don't. Only the base GS without the stage 2 or 3 aero packages has the center air dam in those years. Maybe yours wasn't supposed to have one anyway?
08-28-2018, 06:13 PM
#40
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St. Jude Donor '13
Actually, I intended it to be silly. 
We know that if GM thought they could save a dollar of cost or a pound of weight, they'd get rid of the center piece immediately on the base car.
The answer to your question is somewhere in the "Ask Tadge" section, and also in JerryU's pdf link. Executive summary:
Basically, GM wants the handling of the car to not change at higher speeds, or change as little as possible. A base C7 with the front air dam develops a similar (small) amount of lift at both the front and rear at high speeds, so the "balance" remains about the same. The Z51 and GS have other aero pieces on the car that would cause it to be "nose heavy/tail light" at speed, changing the handling toward possible oversteer if the center air dam were installed, so they deleted it on those cars.
We know that if GM thought they could save a dollar of cost or a pound of weight, they'd get rid of the center piece immediately on the base car.
The answer to your question is somewhere in the "Ask Tadge" section, and also in JerryU's pdf link. Executive summary:
Basically, GM wants the handling of the car to not change at higher speeds, or change as little as possible. A base C7 with the front air dam develops a similar (small) amount of lift at both the front and rear at high speeds, so the "balance" remains about the same. The Z51 and GS have other aero pieces on the car that would cause it to be "nose heavy/tail light" at speed, changing the handling toward possible oversteer if the center air dam were installed, so they deleted it on those cars.
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