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glass vs polycarb front windshield

Old 07-11-2018, 10:40 AM
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KevinGross
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Default glass vs polycarb front windshield

Building a dedicated track-only car, donor vehicle has a broken windshield. I'm allowed to use glass or a polycarbonate front windshield. Opinions on the preferred path? Especially love to hear from those who've gone one route and wish they'd done the other! I am not looking for more TRS (trick racing sh*t) bling to throw at the car, just the best option in terms of optical quality, weight, lifetime, and the stuff that really matters (to me at least). Cheers and TIA.
Old 07-11-2018, 11:25 AM
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maspirito
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Go with glass much less costly and will be much more clear over time . The plastic is a pain to clean and invariably gets scratched and foggy.
Old 07-11-2018, 12:03 PM
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Frank 993 C4S
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I have glass with tear-offs in one race car and polycarbonate in the other race car. Polycarbonate seems to scratch relatively easy so you have to be careful when cleaning it. I see no other real difference between the two.
Old 07-11-2018, 05:14 PM
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alexaqui
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How much weight does polycarbonate save you and are you willing to spend to get to the pointy end of the field? For my car it is quite significant yet the install and thickness added significant cost to the point where I went with glass. You may need bracing and get a coated one to avoid issues mentioned above.
Old 07-11-2018, 06:06 PM
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mark kibort
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Usually, it is a wash with weight, as you need to go much thicker on the front windshield to make it safe, and there are more supports often times. the rear window was a now brainer, a pretty large weight savings, but the front might have been a net of 5-7llbs saved. one draw back on the glass, is that if you pick up a rock from a leading car, it can lead to a crack that will force replacement, depending on the rules of the racing group.
Old 07-11-2018, 10:13 PM
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KevinGross
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Thanks folks for the feedback, it is appreciated.
Old 07-12-2018, 12:24 PM
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autosea
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I would go with the polycarbonate if it is a race car. Is it a 944? I build composite racing sailboats and have been making and installing polycarbonate windows and seen them on the boats last for up to 10 years. Most polycarbonate has a tough shield on both sides. It is very good for abraision. When 911's were cheap and everyone was building track cars I got some great idea to build a oven and make the windshields. I had a mold . would vacuum down the poly and i found thatI couldnt make them for $500 and get my money back. I made a bunch of them and then ditched the whole shebang. When you look at the price of a sheet of poly and can only get two windshields out of a sheet it is amazing that you can buy one for $500 thru GT Racing or Lindsey Racing . I think that is a great deal.I dont think taking care of the windshield is that big of a deal. There are also a lot of new films for windshields availible. With a Carrera GT windshield at $6K these films are necessary.
It is hard to buy a early 944 glass anymore for $150. They are all china.
The late 944 windshield is $600. I have 2 944 race cars. They are or were SP1 so glass is a must. Im going SP3 not sure what rule is but the glass will be gone if I can get away from it. The rear 944 glass is very heavy. It is a perfect candidate for plastic as the curves give it lots of strength
Old 07-12-2018, 02:28 PM
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KevinGross
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Originally Posted by autosea
I would go with the polycarbonate if it is a race car. Is it a 944?
It'll be a Spec Cayman. Thanks for the info and perspectives.
Old 07-12-2018, 02:47 PM
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vwmurph
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Kevin, I have a polycarbonate in my 911. I will be replacing it with glass next time


Aaron Murphy
Old 07-12-2018, 08:23 PM
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linzman
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I have had a rock fly up and break my windshield, ending my weekend early. I'll live with the scratches on the lexan and replace it every 5 years when it gets really hard to see through. Still costs less than 1 weekend ruined. And if you're careful about cleaning, it doesn't scratch that quickly.
Old 07-12-2018, 10:39 PM
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Viperbob1
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http://www.racingshields.com/

We get 2 strong years out of a windshield without any issues. Glass always even with tearoffs can crack and your out of race. Poly is as stronger or stronger than glass windscreen.
Old 07-13-2018, 09:46 AM
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Bob,

Curious which options you choose i.e. clear with anti fog inside? Thickness?

Steve
Old 07-13-2018, 09:56 AM
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jdistefa
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Ran poly on SPB and SPC. Consistently got 2-3 years out of a windshield. Poly is lighter and safer, easy decision. I'd rather have a piece of metal bounce off rather than go through. No affiliation but like Bob, have always used Shields. Order the rain coat and the anti-fog coat.
Old 07-13-2018, 10:46 AM
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dan212
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After I replaced my windshield for the 3rd time one summer by stuff thrown by other cars - including a tailpipe, I switched to polycarb on my dedicated race car.. Took me about 5 minutes to get used to it and it has remained clear for the last couple of years. Since then, I have a had a few other things thrown at me beyond the usual tire snot and pebbles. Glass would have broken a few more times.

Cost aside, i think its frankly safer.

You can wack poly with a hammer and do no harm. The last glass windshield that broke left glass particles on the dash and I kind of took the hint. Also drive with the visor down.


Originally Posted by KevinGross
Building a dedicated track-only car, donor vehicle has a broken windshield. I'm allowed to use glass or a polycarbonate front windshield. Opinions on the preferred path? Especially love to hear from those who've gone one route and wish they'd done the other! I am not looking for more TRS (trick racing sh*t) bling to throw at the car, just the best option in terms of optical quality, weight, lifetime, and the stuff that really matters (to me at least). Cheers and TIA.
Old 07-13-2018, 11:23 AM
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autosea
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i have been building a spec boxter for last few years. The car is at a shop. I took out the old windshield to help build the cage. had a new glass installed. the car isnt finished yet but i noticed when i went by the shop the other day the new glass had a big crack on it

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