Window popped out during high speed run...

[FikseGTS]

"A friend of mine" had just put on some new front tires on his 1996 GTS, and took it for a test drive to see if the tire place had balanced them well...

took the car for a quick spin around the block, re-torqued the lugs and then headed out for an open highway....

in South Floirda, US27 is usually a dead empty highway with VERY long straight portions.... car rode perfect up to 120MPH, then decided to take it a little faster....

as the speedo passed 170MPH, out of nowhere, a VERY LOUD whoooooshing noise occured..... so loud that it sounded like the car had hit something..... after a second, it was realized that the left window had popped out of its groove, thereby causing the scary noise....

after letting off the throttle and coasting down to 150MPH the noise was gone.... window looks fine, but something has to be wrong....

anyone else have this happen?


Brooks

 

[Chuck 98 RT/10]

Many have had the same thing happen. Hasn't happened to me yet but I can't get above 150 on the track and I never exceed the posted speed limit on our highways or 5 mile bridges.

 

[Ron]

<FONT face="Comic Sans MS">Sounds a bit distracting @ 170. Anyone know if there is a fix or adjustment?</FONT f>

 

[Doug Supercharged Vipers]

I've seen it happen from the unequal pressure inside and out. Usually the rear window blows out; typically from blocking the rear vents with luggage or other accessories.

Doug

 

[SapphireGTS]

Last months Viper magazine the SVSi stryker has window clamps. Maybe something like that would work

 

[Frank Parise]

Yes, what your friend experienced is a well-documented condition that was discussed on this Board in considerable detail several years ago. I experienced this frequently in 1998 and 1999 while doing the open road races in Nevada.

The condition exists from a pressure differential created at high speed between the inside of the cockpit, and outside the car (with lower pressure outside than inside). The side windows will expand outward from their mouldings as the higher pressure air inside the car attempts to escape outside into the lower pressure airstream. The sound concussion inside the car when this happens is really scary! There have been documented cases of the rear hatch windows actually exploding, probably because the side windows were sealed so well that this was the only way for the air pressure to relieve itself. Interestingly, when this happens there is no warning. There is no physical sensation to the driver, such as shortness of breath, ear aches, etc. It just happens!

The remedy for this is to remove certain obstructions from the air escape vents that are located at each rear corner. These are the tiny slits that are hidden in the rear corners where the rear quarter panels meet the rear bumper. They are their to allow air displacement in the event that your air bags are deployed. Unfortunately, they do not allow enough air to vent through the cabin at excessively high speeds to avoid the window shattering experience described above.

We corrected this on my car by removing the insulation and dust shields, etc. that cover these slits up. It mitigated, but did not eliminate the problem entirely. The slits are covered at the factory to keep dirt and water out of your rear compartment. If you plan on doing sustained speeds of over 150 MPH or so, I'd suggest you make this fix. Alternatively, you need to vent air out of the car some other way to equalize inside and outside pressure.

Jon B. will remember our past discussions and has probably figured out the best fix. Jon?

 

[ViperGTS]

I had this problem too - above 150/170 mph - had to adjust the door hinges, since the window was not tight enough with the sealing. I had to tilt the door on top a little bit more to the inside to create more pressure between the glass and the sealing.

 

[Ulysses]

You can liken this effect to the hurricane effect on your house. Wind picks up velocity and has a vector parallel to the surface of your house. When this happens the pressure outside is basically nil. The pressure is still the same inside but differentially it is much greater than the pressure outside. Next thing you know, your windows go boom. I suppose you can do what most people who are familiar with twisters do, open your windows. Although, opening your windows will cause more drag.

 

[GTS Dean]

There's a rubber dust/wash water flap that lays over the plastic vent louver in the rear quarters - just under the quarter panel outer skin. The flaps have some weak adhesive along the edges that pulls free when a sudden increase in cabin pressure occurs (displacement by deploying airbags.) However, a gentle rise in interior pressure (with increasing speed), the flaps may remain sealed tightly enough that the windows pop first.

The quick fix is to take off the license plate, then remove the screws that hold the taillight panel to the tub (3 center, 2 in each outer corner.) Pull the carpet down from under the hatch latch, unscrew the retainer nut from the key release assembly, unplug the taillamp wiring connectors and push their body grommets out. Gently wiggle the panel back and remove it. The rubber flaps are right there. Figure on about 30 minutes to R&R the panel.

 

[scottgf]

What are these "window" things anyhow?......I cant seem to get mine to roll up....

 

[Ron]

<FONT face="Comic Sans MS">A few questions:

1) I assume it would be wise to shut off the ventilation system during runs like this is minimize inflow?

2) If one was to block the air intake under the speaker grill, would that eliminate the source of the internal pressure?

3) GTS Dean, once you reach the flaps, what do you suggest, removing the adhesive or the flaps entirely.

4) Lastly, Jon, is it a flap change year to year, thereby upgradable or is it more structural?

Thanks....</FONT f>

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Doug Supercharged Vipers:
I've seen it happen from the unequal pressure inside and out. Usually the rear window blows out; typically from blocking the rear vents with luggage or other accessories. <HR></BLOCKQUOTE>

The "keeper" tab at the A-pillar-to-roof seam can be carefully bent inward about 1/16th to help. But consider:

I bet your windows were NOT full-up, and checked. Hit the switch 2-3 times.

The Year Matters.... the GTS rear panel cargo vents help equalize pressure at high speed, and during airbag deployment. There were 3 vent iterations from 96-97 to get it right. IF you block these vents, you exacerbate the problem........

ps.... 170mph on public roads? That sound might have been brains leaking out !

 

[GTS Dean]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Ron:
<FONT face="Comic Sans MS">A few questions:

3) GTS Dean, once you reach the flaps, what do you suggest, removing the adhesive or the flaps entirely.

Thanks....</FONT f>

<HR></BLOCKQUOTE>

Ron,

What I did was just lift the flaps away from the louvers and try to rub the adhesive off. Best to leave them on a street car, or else the garden hose or car wash wand will find a way to wet the trunk area of your GTS.