Sunroof on a track day car = Danger
07-15-2006, 06:31 PM
#16
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The sunroof equipped car is arguably safer and more rigid because there are additional structural members installed to mount the sunroof. 
One needs to distinguish structural elements from cosmetic elements as NOBLEGT3 has pointed out.
One needs to distinguish structural elements from cosmetic elements as NOBLEGT3 has pointed out.
07-15-2006, 06:32 PM
#17
AND HERE IS THE NEW CORVETTE ZO6 ROOF AFTER THE COVERING PANEL BLEW OFF...LOOKS LIKE A HOLE TO ME?? DO YOU THINK THE PANEL THAT BLEW OFF MAKES A HUGE DIFFERENCE COMPARED TO A STEEL SUNROOF THAT IS CLOSED??
07-15-2006, 09:14 PM
#20
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Originally Posted by NJ-GT
Have you seen a car with a sunroof on a rollover accident? The metal roof cover moves, your head and hands will be rubbing pavement at speed, the sunroof itself becomes a razor.
Originally Posted by NJ-GT
A friend of mine cut his finger on a rollover accident in a BMW with a metal sunroof. I know from someone else that cut his forehead with the sunroof edge on a rollover accident.
Originally Posted by NJ-GT
There is the chassis rigidity factor as well. A stiff body improves handling, it's stronger and safer. Porsche claims a 40% stiffer body on the 997 C2 compared to the 996 C2. The new 997 C4 body is just 10% stiffer than the 996 C4 body, the 996 C4 body is the one used on the 996 GT3. I know the 997 GT3 RS will be based on the new 997 C4 body, but no idea about the body used for the 997 GT3. That 10% improvement in rigidity over the 996 GT3 will be gone the moment a sunroof is installed.
A car without sunroof is safer in an accident, by resisting deformation better than a car with sunroof.
A car without sunroof is safer in an accident, by resisting deformation better than a car with sunroof.
The thing with sunroofs though, is that it adds weight and roll inertia at the worst possible location for a track car, up high above the center of gravity and roll center of the car.
07-15-2006, 09:47 PM
#21
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Originally Posted by RonCT
I'm a little shocked at the rude responses to this post. A member raises a legitimate thought, shares it with the group, and is berated.
Do any companies make replacement glass sunroof panels, ala the old 944 sunroof replacement?
07-15-2006, 09:59 PM
#22
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Originally Posted by enthusiast
XSpeedFreakX;
Why is that the case? Is it because they only make one roll bar and it is designed to fit close to the non sunroof interior roof structure?
Why is that the case? Is it because they only make one roll bar and it is designed to fit close to the non sunroof interior roof structure?
You nailed it.
07-16-2006, 12:59 AM
#23
Originally Posted by Vancouver83LTD
No kidding.
Do any companies make replacement glass sunroof panels, ala the old 944 sunroof replacement?
Do any companies make replacement glass sunroof panels, ala the old 944 sunroof replacement?
yes and fuzzy dice and a chain steering wheel...are you high or what??
07-16-2006, 01:49 AM
#24
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Originally Posted by frank320
... As an example, the "structural rigidity" of your house is determined by the foundations laid, the number, placement and strength of the pillars between the foundations and the rest of the house, and of course, the design of the house. It is most definitely NOT determined by the sheetrock or drywall used to separate and create walls and rooms.
Are you an architect? (By the way, neither am I
)The plywood on the exterior of a house DOES indeed make the structure more rigid. And sheetrock also makes either wood framed or metal stud framed walls more rigid. The interior walls that tie into the structural members of the house DO indeed help stiffen the overall structure. Think about it: Take a wood frame wall that is nailed or screwed together and push on the top corner and see what happens. Now screw some drywall on and try again.
Anyhow, although I agree that this "hole" sunroof thing is getting blown way out of proportion, you would be surprised how much rigidity is added by that thin sheet metal.
My .02.
07-16-2006, 02:27 AM
#25
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In the Porsche 996 the roof is welded to the upper side sections. It's a structural component, and the analogy with a house is incorrect. A house is not a moving object, the foundations support mostly a vertical load. A car support loads in every dimension, in every direction.
To explain the roof as a strucutal component, imagine not having that metal cover welded to the upper side frames, in case of a lateral impact, the side frames will bend easier.
The 997 GT3 RSR has a 10% stiffer body than the 996 GT3 RSR per recent press material from the new RSR. The 996 RSR, 996 Cup use the same body as the 996 GT3/GT3RS. The new road car 997 GT3 RS wide body is the homologation for the 997 RSR. Neither RSR has a sunroof, so the 10% refers to non-sunroof cars compared.
To explain the roof as a strucutal component, imagine not having that metal cover welded to the upper side frames, in case of a lateral impact, the side frames will bend easier.
The 997 GT3 RSR has a 10% stiffer body than the 996 GT3 RSR per recent press material from the new RSR. The 996 RSR, 996 Cup use the same body as the 996 GT3/GT3RS. The new road car 997 GT3 RS wide body is the homologation for the 997 RSR. Neither RSR has a sunroof, so the 10% refers to non-sunroof cars compared.
07-16-2006, 02:37 AM
#26
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Originally Posted by NOBLEGT3
AND HERE IS THE NEW CORVETTE ZO6 ROOF AFTER THE COVERING PANEL BLEW OFF...LOOKS LIKE A HOLE TO ME?? DO YOU THINK THE PANEL THAT BLEW OFF MAKES A HUGE DIFFERENCE COMPARED TO A STEEL SUNROOF THAT IS CLOSED??
From the safety standpoint, well is a flying top safe?
07-16-2006, 09:20 AM
#27
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Originally Posted by NJ-GT
The 997 GT3 RSR has a 10% stiffer body than the 996 GT3 RSR per recent press material from the new RSR. The 996 RSR, 996 Cup use the same body as the 996 GT3/GT3RS. The new road car 997 GT3 RS wide body is the homologation for the 997 RSR. Neither RSR has a sunroof, so the 10% refers to non-sunroof cars compared.
07-16-2006, 01:20 PM
#29
Originally Posted by NJ-GT
In this case, that panel is glued to the structural component, but the panel itself is not a structural component. The structural component is the Magnesium cradle bolted to the A and B pillar, to increase rigidity in the Z06 compared to the Vette Coupe.
From the safety standpoint, well is a flying top safe?
From the safety standpoint, well is a flying top safe?
the point is a hole doesnt mean its not designed right or not designed strong enough. the porsche engineers will make the GT3 right whether its has a sunroof or not
07-16-2006, 01:21 PM
#30
Originally Posted by DanH
So can you not fit the OEM cage in a 997 GT3 due to the sunroof? Surely that's more annoying than the fact it is there?