Re: Planning Honda Civic Wagovan Hybrid Electric/Pedal Conversion
I wouldn't replace the glass for a number of reasons:
1. The glass is curved. The replacements won't be. That's a problem. Unless you want to make wooden bucks and have an oven big enough to mold your replacements over them, they'll never fit right. The windows won't roll up and down properly.
2. The windshield isn't worth doing, especially without a molded exact replacement available. Also, it won't be DOT compliant for road use.
3. Polycarbonate is not that much lighter in the same thickness. If you go thinner on the plastic, you have to re-engineer the seals and mounting system (like adding rivets) to be water and air tight.
4. Polycarbonate scratches easily. Percy's Speedglas is much better, but expensive and harder to work with. Side windows of lexan that roll up and down will look terrible in no time at all.
5. Most Polycarbonate isn't UV stable, and even the "UV Stabilized" stuff will ultimately yellow, fog, craze and embrittle in the sun, just like the headlight covers on most cars.
On balance, replacing the side windows with lightweight plastic is one of those great ideas that turns out to be a ton of work, very difficult to make air and water tight, and ends up being FAR less durable and functional that OEM glass- even if it doesn't leak or whistle. If you had a kit car, or an old car with flat glass mounted in steel frames, then it would be worth looking into, but on a modern car for which curved Speedglas replacements are not available, its just not worth doing.