False windshield for boxy car?

[tasdrouille]

Just a note. With the current design shown in the pics, the A-pillar vortexes will still be present and they will be pretty strong. You need to round those corners off in order to minimize drag.

[brucepick]

Thanks guys.

Hinge at front = good idea.
Hood front edge is wider than roof - so when you open it as basjoos says, it is wider than roof and will slide back onto roof.

Good to hear about the leak-through and condensation problem. Forewarned is forearmed, so they say.

I also thought about the lack of air to the cabin sanity system. Maybe openings at front corners of the false windshield to let air in - run it thru some kind of drip can like in a pcv system and let the air pressurize the chamber just a bit.

A-pillar thing should be OK. (I'm talking about the first pic idea.) What the pics don't show is that there's a very non-aero rain gutter running up the A-pillar, with the edge facing forward. Right along the outer edge of A-pillar. The gutter continues up and just curves to become the roof side gutter. Anyway that gutter edge becomes the lip that holds the Lexan side panel's rear edge in place. Should be no vortex along the pillar, or only due to side window being a bit recessed.

Maybe some turbulence where false wndshld meets the roof. But it should be a lot better than what it is now. I'd have to make it match the existing curve well so the air just glides across...

[basjoos]

Originally Posted by tasdrouille

Just a note. With the current design shown in the pics, the A-pillar vortexes will still be present and they will be pretty strong. You need to round those corners off in order to minimize drag.

I used a plexiglas airplane canopy as a model in desiging my false windshield using rounded curves in the area of the false windshield's A-pillars.

Interestingly, if you look at some of those 1930's German aero cars, a number of them have rounded A-pillars even though they still had a stepped windshield. They didn't have the technology in the form of glazing or fabricating skills in the 30's to produce the long sloping windshields that we see today and even aircraft built in the 1930's had stepped windshields.

[tjts1]

At some point you have to wonder, am I better off just getting another car? The new Civic has the most raked windshield in the industry at 20 degrees from horizontal.

[elhigh]

They did something like this in "Tango&Cash," a dreadful movie with an even worse plot. I did like the way it totally changed the appearance of an otherwise unaltered car (though you could see the original windshield still in place in a couple of brief shots). But it rains too much for me to really consider it here.

[trebuchet03]

Originally Posted by tjts1

At some point you have to wonder, am I better off just getting another car?

Typically, the answer is no

[brucepick]

Here's 2 pics of basjoos' false windshield.
(Basjoos, I hope you don't mind that I grabbed them from your photobucket page and shared it here.)

I like the curve seen when viewing the profile. Due to the additional slight curve in the other direction at hood and roof edge I think it ends up being a compound curve. My car also has curves going across the roof and hood's leading edges. In vinyl it makes a few wrinkles but I think in Lexan it may be another story.

[LostCause]

1.) Building a windshield wiper fairing won't do much as your wipers are probably in a stagnation region with little airflow anyways.

2.) Raking back the windshield doesn't seem to reduce drag as much as you'd expect, at least from what I've gathered. Raking does help, but it has diminishing returns beyond a certain point (I don't remember what that point is: it is a sharper angle than your's but much less than the new civic's). I guess what I'm trying to say is that a fairing will probably help, but not to the extent that a boattail/kammback would. Personally, I'd work on rounding the a-pillars (get rid of that rain gutter), streamline the frontend (Bumper/radiator) and add a partial kammback. Front wheel fairings, catamaraning the bottom, and ducting the radiator flow onto the hood are other untapped, incognito possibilities.

I would be very interested to see the results of your experiment, just don't forget that the best fruit isn't always at the top of the tree.

3.) Polycarbonate (Lexan) and Acrylic (Plexiglass) scratch extremely easily if not coated. Acrylic is much more transparent (optical grade is better than glass), but both would certainly suffice. Lexan has the added benefit of increased impact resistance. If you want to keep the fairing long term, be sure to get plastic with uv inhibitors, as both yellow in the sun.

[diesel_john]

the best car is the one that your are not concerned about drilling holes in.

below my version of false windshield. is it too rad?

[brucepick]

Originally Posted by diesel_john

the best car is the one that your are not concerned about drilling holes in.

Yup. '89 Euro-beast with 315K mi. on the clock might qualify.