Cracked Windshield
#17
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I have been less than greatly impressed with the strength of the Porsche windshield. After my first track day, the windshield was peppered with at least 4 or 5 chips - and this without any event that caught my attention.
This is why I wonder why folks are so down on the aftermarket replacements. Are there known problems, or is it a question of "it's not a Porsche part."
Cheers
Rich B
This is why I wonder why folks are so down on the aftermarket replacements. Are there known problems, or is it a question of "it's not a Porsche part."
Cheers
Rich B
#18
Three Wheelin'
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I have been less than greatly impressed with the strength of the Porsche windshield. After my first track day, the windshield was peppered with at least 4 or 5 chips - and this without any event that caught my attention.
This is why I wonder why folks are so down on the aftermarket replacements. Are there known problems, or is it a question of "it's not a Porsche part."
Cheers
Rich B
This is why I wonder why folks are so down on the aftermarket replacements. Are there known problems, or is it a question of "it's not a Porsche part."
Cheers
Rich B
#19
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Maybe double up on the Clearplex?
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#21
Burning Brakes
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Seems like the Bray Group offering would be the better decision. I have no affiliation (aside from the product being installed on my GT4) just seems like you could get into optical issues doubling up a product that isn't designed to be, plus I don't even know if it would stick to itself and you'd probably get bubbles and ripples etc where the Bray product is built and designed to layer and comes "doubled" from the factory.
#22
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"hit a rock"
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#23
#24
Burning Brakes
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I just wanted to update anyone considering windshield protection that I took a fist size rock strike to my windshield with Bray protection at roughly 80 mph. (Rock flew off a industrial size dump truck was going 50 in opposite direction I was going 35-40mph)
My 5 year old daughter was in the car and it sounded like a gunshot. It was so loud and unexpected I jumped in the seat. I feel if I had not had the Bray film the rock would have been in the cabin with us. It was that large and moving that fast. I thought for sure I was going to need a new windshield.
Here is the video of the removal of both layers of protection:
Even after the two layers tore off we thought I needed a new windshield but what we thought was the chip/crack was actually the Bray material crushed. It was removed with a fingernail and all that was left in my glass was a tiny scratch smaller than the ball of a ball point pen. Very very impressed with this product.
My 5 year old daughter was in the car and it sounded like a gunshot. It was so loud and unexpected I jumped in the seat. I feel if I had not had the Bray film the rock would have been in the cabin with us. It was that large and moving that fast. I thought for sure I was going to need a new windshield.
Here is the video of the removal of both layers of protection:
Facebook Post
Even after the two layers tore off we thought I needed a new windshield but what we thought was the chip/crack was actually the Bray material crushed. It was removed with a fingernail and all that was left in my glass was a tiny scratch smaller than the ball of a ball point pen. Very very impressed with this product.
#25
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I just wanted to update anyone considering windshield protection that I took a fist size rock strike to my windshield with Bray protection at roughly 80 mph. (Rock flew off a industrial size dump truck was going 50 in opposite direction I was going 35-40mph)
My 5 year old daughter was in the car and it sounded like a gunshot. It was so loud and unexpected I jumped in the seat. I feel if I had not had the Bray film the rock would have been in the cabin with us. It was that large and moving that fast. I thought for sure I was going to need a new windshield.
Here is the video of the removal of both layers of protection:
https://www.facebook.com/automobilia...type=2&theater
Even after the two layers tore off we thought I needed a new windshield but what we thought was the chip/crack was actually the Bray material crushed. It was removed with a fingernail and all that was left in my glass was a tiny scratch smaller than the ball of a ball point pen. Very very impressed with this product.
My 5 year old daughter was in the car and it sounded like a gunshot. It was so loud and unexpected I jumped in the seat. I feel if I had not had the Bray film the rock would have been in the cabin with us. It was that large and moving that fast. I thought for sure I was going to need a new windshield.
Here is the video of the removal of both layers of protection:
https://www.facebook.com/automobilia...type=2&theater
Even after the two layers tore off we thought I needed a new windshield but what we thought was the chip/crack was actually the Bray material crushed. It was removed with a fingernail and all that was left in my glass was a tiny scratch smaller than the ball of a ball point pen. Very very impressed with this product.
#27
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Thanks Jenner, as you point out the fact that the Bray material was crushed shows that it did absorb some of the impact energy. However, I do take exception with the physics and math you are using to demonstrate the speed (80mph) of the rock.
Your speed of 35mph can definitely be used as one component of the impact energy. However, the truck’s forward speed cannot directly be used, unless the rock was sitting on the hood and the truck came to an immediate stop. In this case, the rock would not stop with the truck, but would be launched forward with an initial speed of 50mph.
In practice rocks tend to usually fall backward from moving trucks, lose momentum quickly, drop like the proverbial stone and either bounce off the road or hang in the air momentarily for you to run into. Or, sometimes truck tires shoot out rocks, but due to tire rotation, they are typically propelled in reverse to the truck’s forward motion.
Our car has a bunch of the same tiny pits that you experienced. Due to the 911’s low stance and sloping windshield we have been lucky that all our impacts have been glancing blows, even though some of them sounded, as did yours, like a gunshot.
These windshield wraps are ok, great even for collector cars that do not live in a scratchy work-a-day world. However they’re not Jesus, they won’t save from a genuine big o’ high-speed head-on rock impact.
Your speed of 35mph can definitely be used as one component of the impact energy. However, the truck’s forward speed cannot directly be used, unless the rock was sitting on the hood and the truck came to an immediate stop. In this case, the rock would not stop with the truck, but would be launched forward with an initial speed of 50mph.
In practice rocks tend to usually fall backward from moving trucks, lose momentum quickly, drop like the proverbial stone and either bounce off the road or hang in the air momentarily for you to run into. Or, sometimes truck tires shoot out rocks, but due to tire rotation, they are typically propelled in reverse to the truck’s forward motion.
Our car has a bunch of the same tiny pits that you experienced. Due to the 911’s low stance and sloping windshield we have been lucky that all our impacts have been glancing blows, even though some of them sounded, as did yours, like a gunshot.
These windshield wraps are ok, great even for collector cars that do not live in a scratchy work-a-day world. However they’re not Jesus, they won’t save from a genuine big o’ high-speed head-on rock impact.
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#28
Burning Brakes
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I believe a stationary object traveling on a moving object is going the same speed as the moving object. I get that it would bleed speed due to air resistance as it fell but at the same time wasn't trying to be exact or scientific, it was a guesstimate. I have no proof of how fast the truck was going in the first place but he was flying.
Even if we assume a 60mph impact and a 3" diameter rock its still moving fast and large.
In the end the film exceeded my expectations and I'm very happy with it. Just trying to share my personal experience with others.
Thanks for your analysis.
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Last edited by Jenner; 05-27-2016 at 08:59 AM.
#29
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I received a small pebble 2 weeks ago that made a mark in the windshield. I was able to have it repaired before a DE on Monday and Tuesday. Then I saw Tuesday that my windshield was cracked at a different place and there was a slight impact showing. Never saw or heard it.
From 8 GT4 at the DE, we were 2 that got cracked windshields. They do seem pretty week....
From 8 GT4 at the DE, we were 2 that got cracked windshields. They do seem pretty week....
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#30
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Maybe it's time to just finally opt for windshield insurance for the peace of mind. I live in rocksville, but I've usually gotten away with immediately filling my chips. Worked well on the 1m.