baloga41

I decided to take the side windows off for weight reduction, and tried to find lexan ones. Then someone told me that some C5Rs cars run open windows. How could they do that? I know open windows will slow that car a lot and will work as a parachute.

L98Terror

Check class rules most cars have to run without windows

Jason

Most clubs that you'll ever run with require windows to be down to allow emergency crews easier access to the driver.

fatbillybob

the real question is if you have an open trailer and you take the windows out how do you secure the car during transport and nightime hotel stays? I would delete my electric windows if I could figure that one out.

Jason

Cobra4b worked on that problem a couple of years ago I think. Might shoot him a PM and see what he came up with.

c4cruiser

Full-blown race cars like the C5R and C6R will use aerodynamic panels to let air flow past the window opening without causing drag. They use window nets for safety.

As stated, most HPDE events require cars to run with windows down. While there may be some decent weight savings by removing the windows, street cars still would have a security issue with no glass and lexan would probably wind up being scratched over the years as the windows are ran up and down.

I would expect that the dollar amounts for custom fit Lexan windows could be put to better use elsewhere like building a few more HP into the engine which would compensate for a few pounds of glass.

davidfarmer

In World Challenge, one of the teams tried for years to get SCCA to allow a vertical "bulkhead" to be inserted behind the drivers' seat to reduce the "parachute" effect. Basically extend a vertical piece of lexan from the rear firewall (the bump behind your seat) straight up to the roof.

I can't verify that it would have helped or if it was ever approved (after I left the series) but they pushed hard for it.

fatbillybob

We all remember the scary fire dale jr had in a C5R. If the vert bulkhead was there it would segment off the fuel cell better than the designs we currently use. The safety of the modification is much more important than the aero benefit.

John Shiels

What does the glass weigh? MR10 will not scratch easy.` I wanted to get a old window to see how hard it is to copy in lexan.

I don't think having the windows open is a drastic reduction in speed.

John Shiels

he has not been on here in ages?

davidfarmer

those cars are nothing like ours. There is already a steel bulkhead all the way around the tank, adding a second bulkhead would only improve access from the back halves of the tanks.

I agree that actual overall performance gains are likely very slim, but wind tunnel testing showed that all sort of minor changes made measurable improvements. For instance, "rounding" of the b-pillar edge (where the door glass touches the weatherstripping) made improvements in drag and down-force. Closing off the fender openings a certain way made improvements. These things add up for anyone who is interested in pushing the envelope (I never got that hung up on details....my time/money had better places to be)

RaleighSS

never thought about the negative effect of having the windows down.... does this cost ya 1 or 2 MPH on the back of VIR?

Git Er Dun

Here's my gutted out all fiberglass bodied C4 that weighs 2780 pounds with 3/4 fuel. It's a VERY rough gut out but it served it's purpose and it's NO show car.

Before:


After the grinder:








YES the car is still "road legal..." it has 94 Camaro DOT headlights where the fog lights used to be. Next to them are DOT legal motorcycle turn signals.



Rocking the El Camino mode (removable Lexan rear window that is hood pinned on):


Since it's still is able to drive on the street I wanted something to keep rain out just incase it rained on a road trip or at the track (I don't use them while driving on track but if you don't have an awning when you park the car then at least this will keep most of the rain out.) We had a boat canvas shop that makes a lot of big house boat/yacht stuff give us the clear plastic that is used for plastic boat windows or convertible cars back windows sometimes. We cut that to fit and circled where we wanted her to put the snaps. She added a nice black border and re-enforced the snap area. She then gave me rivets with snaps on the end of them so basically snap rivets. Now when it rains I simply snap in the windows and it keeps most of the rain out. We kept the windows a little baggy so that it wouldn't be to hard to snap them. Unfortunatly I don't have any pictures of them snapped in but they do indeed work in the rain. They also help hold a little bit of heat in when it's cold out. It also makes it easier to wash a car with no side windows...though it does get some water inside when I wash it, it doesn't really matter since there's no carpet or anything.

Obviously it's not the best thing for a typically street driven car. I do have a kill switch hidden since there are no windows. We left the lock mechanism on the door so if a person is to big to fit through the window or between the steering wheel and seat and can't figure out how to work the door lock from inside the door using the cut off door lock rod then maybe they wouldn't even steal the car...and there's nothing inside really worth stealing besides the seats, harnesses, and fire extinguisher.

If you really need pictures of the window in place I'm sure I could take some sometime. PS we chose snaps instead of a zipper because we figured they would be more durable and in case you need to get out fast you can just punch the window and it will unsnap I'm sure and you won't have to worry about trying to work the zipper or having it jam.

MySR71

Could something like this be made to work? Sorry for the bad drawing but it is supposed to be a cross section of the door.



The window would removed during track events. To install the window, an aluminum trough/insert would be placed between the door's inner and outer door panels and the glass would sit inside the insert. The window wouldn't be able to go up and down, but maybe it would be held in the proper position to give enough security and rain protection.

eogel

To keep rain out, I have a tonneau that snaps over the top, front, back, and side windows. Sort of like a boat cover. Does not provide security, but that has not been an issue in 9 years of racing.

Git Er Dun,

I did what you have done and dropped 18.5 lbs per side. That includes removing the metal bar still in your door. I think that bar alone weighs 7-8lbs. It will not stop something coming in, but satisfied the legal requirements and advertising needs of a production street car. It is not an issue is you have a cage with side bars.

Ed

fatbillybob

Good idea but at 80mph towing and winds from front side or back there is an amazing amount of force on those windows and even when stock I have driven 80mph in a side wind and have the top lip of the window lift out away from the car. I don't see how I could get your idea to work but the concept is good.

MySR71

That may very well be. Ideally, the aluminum insert would be sized in depth to make the window sit at its normal full up position. Then the insert and window would be installed with the door opened, then the door closed when done. My intent was to have the top of the window sit where it normally does and thus secured/trapped just like normal. However, maybe this isn't really possible when all is said and done and/or it won't be secure enough.

Git Er Dun

I know that my snap in windows have been tested to about 80-90 mph and showed no signs of wanting to un-snap. They probably would blow into the car if they did happen to un-snap.

Eogel I wanted to take the inside door bar out but right now I only have a roll bar (welded in) and no side door bars. I eventually want to finish off a cage and when I do that I will be able to remove those bars but I was concerned that without door bars the door would flex to much or eventually deform over time so for right now I will keep the extra 16 or so pounds.

fatbillybob

got pics of the snap in windows?

Git Er Dun

No but I could probably take some sometime. I will try to get some soon.