If you had the $$$..... would you
 

I have been lurking for a while now...... and I am starting my journey for better fuel economy. I like the kammback which is going to be one of the first mods I am going do to a metro. Anyways If you had the cash would you get this type of windshield...... do not know if this has been addressed before .

http://i43.photobucket.com/albums/e371/AndrewGS/187.jpg

Phil has been toying with the idea of getting a windshield like that, but I forget what he was going to use it on.

http://www.autoblog.com.es/fotos/mercedes/c1113.jpg

The Mercedes C-111 (0.178 drag coefficient) had a windshield similar to that, but there are plenty of examples of vehicles with low Cd's that have conventional glass. EV1, the PNGV concept vehicles, Mercedes Boxfish car...

Mike had one on his aerocivic for a while, but I don't think it's on right now. I would rather have a car that used the design idea without looking like crap, though :)

speaking of design... you wouldnt want a windshield like the one in the original post. looks like a 90s chevy full size, now they might be reliable, but sooner or later youre going to want to open that hood.

The dash on that truck would be outrageous.

Guys - you'd have heat w/o running the blower in the winter. Since the hood area is now completely inside the truck, you could adjust the heat by adding/subtracting grille block!

To answer your question: No, I would not spend the money on the windshield


its a good way to improve aero but imho that money would be better spent towards something else (perhaps a better aero shell for the metro)


thats what i tell myself everytime i want to pay a shop to make professional (insight grade) wheel skirts for my car

it would be cool but the whole point is to save money and gas

Negotiate -

Tell them that if they can make them at low/reduced cost, you'll allow them to advertise your vehicle's image, and you'll apply one (1) vinyl decal with their logo of choice to your vehicle, for a pre-determined amount of time. (1 year, usually).

Maybe they'll go for it.

That has it's own rewards, too. You get cheap/at cost parts, professionally made, and they get cheap/free mobile advertising, which brings a new revenue stream.

Christ is on to something here. Take into account that a professionally modded car will get much more attention than a normal one. Gee, maybe they should pay you for their ad?

I asked around at the local body shops before doing my mods on my own and nobody wanted to have anything to do with it. They wouldn't even do something small, like removing the roof railing.

my neons front windshield is already slanted a shload so I don't think I would need one but honestly it looks awesome to me, If I was a truck then sure I would want one for free or something

Actually, the headlights and flat grill means it's a 88 or 89, 90-98 had composite one-piece headlights. also looks like 94-01 dodge dually rear fenders mounted on the front.
And, I'm pretty sure that although that windshield would probably help one's mpg's, it would dangerously decrease visibility where the front meets the sides and the cost of the custom 40-inch wipers would probably offset the fuel savings lol

Like so.... http://ecomodder.com/forum/attachmen...1&d=1252910260

Ill take it a step further.

I probably wouldnt pay a shop to do it.

Instead I would ask around to see if anyone
needs a side job and then barter for some/all of it.

I'd go with the skirts and roof extension. In (random)fact, why not go all out with the roof extension, with a hinge to allow trunk access? Also, an aggressive nose job would score points.

http://ecomodder.com/forum/attachmen...5&d=1252915628

On the other hand, if you're mostly city driving, then weight reduction and reducing RR might be better.

http://dealerrevs.com/pictures/13279949.jpg

Maybe something like this? I have one, the dash is like 3 feet long and not moveable, it is a royal pain to work on. Getting to the back of the engine requires laying on your belly and stuffing your head and arms back there, and I'm small too. If the engine ever goes, it would have to come out from the bottom.

On the truck in the original post, I wonder if the whole thing opens for engine access.

Your dash is longer than mine... and I have at least 2 feet from tip to windshield LOL.

There's this giant black panel in there that I thought about putting solar panels on, but the cost is still prohibitive.

The truck in the top picture is, I'm pretty sure, a screencap from the movie Tango and Cash.

Dumb movie. It did introduce the definition of the word "FUBAR" to everyone, however. So there's that.

Would I do that? Maybe, if I had the money. My truck is pretty upright, and a longer slope would open the hole in the air a bit more gradually. However, I wouldn't bother until I had already done a kammback to take full advantage of the smoother flow coming over and around the front.

A quote from Hot Rods article entitled " Wind Camp"
Concerning aero 'myths' -
" The biggie: windshield rake: According to Eaker, "Here's a myth I can bust. Once the windshield is past 45 degrees of rake-and many stock cars average like 60 degrees-you will not see an improvement from laying it down at an even steeper angle." We proved this on the Camaro, building a hugely sloped "windshield" out of foam core. It did nothing."

This quote comes from the guy that runs the A2 wind tunnel, and worked on the EV-1 aerodynamics.

( Am I the only one that would love to invite him over to our site ? )

Here is a link to the article : Car Aerodynamics - Hot Rod Magazine

BTW, Note that this is a several page article

Cd - you have to consider that they were testing a stock car with a naturally high Cd, though, and no airflow improvement at the rear. Obviously, any change to the windshield angle would not alone be the end-all be-all of aero, but would work as an aide to keeping the flow smooth over the top of the car and off the boat tail, if it existed.

What I'm saying is that there might be more of a gain if the car had other aero mods.

didnt they get down to a cd of like .20 or some awesomely low number?

the backside of those camaros looks pretty aero to me, especially thiers that looks like it has some rake to the whole car

I'm not necessarily saying they were incorrect with that statement, and yes, they got that camaro down close to .20 cd - but there was no real scientific testing laid out there...

IOW - Who knows what laying the windshield back would do on a car with a less aero profile? Who knows what mods were already in place on his car that might deaden the effect of the windshield mod? Who knows that there wasn't some improvement that was unnoticed because such a large cross section of the vehicle was changed?

They added foam core to the car to make the steeper angle, which means they had to add the foam from the upper ridge of the windshield (brow bar) to the hood line, somewhere that would make 60*. This would effectively make the nose of the car shorter. Does this have an effect on cd? Can you say for sure without really testing it? I can't!

Here's a fact: To properly "lay back" a windshield, you have to chop the top. That means a reduction in frontal area, as well as a smoother rake to the windshield line. NOW do you think it would have an aero effect?

Actually I don't think it's a good way to improve aero.

It probably isn't necessary.

As we know, most of the action is towards the rear.

As long as it's attached up to the point of max x-section area, that's pretty much all it takes to make the air happy (yeah gross simplification but whatever).

Then there's the weirdness of looking through a windshield that gives you the impression of driving from the back seat. And the solar gain. And maybe fogging (it's 3x bigger).

are ya sure?

now yer throwin other stuff in there, no fair.

Haven't we had conversation here about distortion at extreme windshield angles?
Seems Basjoos has the same issue with his 'tail but it's less relevant in the rear...

windshield
 

There are GTP car windshields available from kit car manufactures for about $3,000 US.These seem to have the best aerodynamic attributes of any laminated safety glass ( a must in the USA ) windshield available at any price.This is on my shopping list for the Dodge D-100 project.To use this glass will require major surgery to the cab,something I'm will to do with the Dodge.--------- In the meantime,I have a rear windshield from a 1995 Camaro/Firebird which may find it's way into high speed air on the front of the T-100.---------- The EV-1 had a beautiful full wrap-around semispherical windshield,however,because of it's demise,we no longer have access to that speed/mpg equipment.What a loss!!!!!!!!!!!!!!!!!!

Isn't that only relevant with plexi or lexan? If you use real glass then I don't think that problem exists. If it did, then I wonder how you would see driving something like this:
http://www.marshu.com/images-website...i-countach.jpg

Funny things happen when light rays hit transparent media like glass or plastic at shallow (small) angles. In physics/optics this is known as the angle of refraction vs the angle of reflection, along with the "critical angle" where all light gets reflected rather than passing through the glass.

Here's a nice diagram to illustrate the phenomenon:

angle of incidence: angles of refraction and reflection on glass :: industrial glass -- Britannica Online Encyclopedia

This is not a perfect analogy, but pretty good: if you shoot a bullet at water at 90 degrees, it easily penetrates the water. If you shoot the bullet at the water at a very shallow angle, like five degrees, it will almost always "skip" and be "reflected" by the water. It can't penetrate the surface. Same deal with photons and glass/plastic. This turns out to have all kinds of repercussions for windshields and headlights with shallow/extreme angles of incidence.


I'm an optometrist, so this is a subject of some interest to me.

Finest regards,

troy

Dang you! I saw that photo and was hoping to be the first person to ID that vehicle - I specifically recall Kurt Russell referring to it as an "RV from Hell"
... and that movie was hilarious! Awful, but good for enjoyment. Love the opening scene where Stallone shoots the gas tanker big-rig drivers...the truck stops magically and the drivers fly out of the windshield upon its final stop - totally unexplainable by physics but amusing.
Oh, and wasn't FUBAR in Full Metal Jacket before Tango & Cash? hmmm... time for some movie research for me!

FMJ was a damn good movie.

And physics doesn't exist in Hollywood, man... The laws of existence are for mortals, not movie-stars.

Sigh, me too. :p
And stop raggin' on one of my favorite movies! Ha ha! Any movie with Teri Hatcher in it can't be that bad, can it? ;)