fresh air vent

[thommysgarage]

What type of fresh air vent is commonly used on a door slammer car? I' ve looked at a lot of pictures, but don't see what is being used. I have moved the firewall back about 8 inches, to the base of the windshield, so the original cowl vents are not there.

[wheelrdealer]

http://www.landracing.com/forum/index.php/topic,12244.0.htmlhttp:

TG

I asked a similar question in the link above. My GGALT originaly had a 1 3/4 piece of conduit bent to go from the left turn signal area behind the front valence to the firewall where the original wire harness passed through. Seemed to work ok. But it was ugly. Camaro windows don't seem to work for NACA Ducts at least the ones I can find. All were 2 1/2" to 3". If I could find a small say 1- 1 1/2" NACA I could make that work but never found one. Also I did not want too much air that may cause my windows to push out at the top. I ordered some 1 1/3 aluminum tubing and some elbow and will tig weld a new vent pipe and plumb through the firewall. It will fit behind the wheel well inside the hollow area of the fender. I guess I will have to build some connections to be able to get the fender off. Have not thought that far ahead yet.

Good luck,

BR 

[jimmy six]

Wheeler--- I like what you did. If you ever run El Mirage you will know what I mean..

Thommys you don't say what it is on but this is what I have seen. Reverse louvers in the top near the windshield. Circular air intakes for private aircraft in the lexan side windows, Small air scoops where the original side mirrors were........Good luck

[38flattie]

We removed the winshield wiper assembly, then boxed that opening in, continuing on into the drivers compartment, on the drivers side. Our firewall, like yours, is recessed.

[jl222]

  We use a small scoop about 1'' wide by 3/8'' high and 11/2'' long with a 1/2 flat area on 3 sides which we
 pop riveted on the front part of the Camaro window that doesn't open.

  Been a while but I think I got it at a Marine supply store.
  If to much we close up inside opening.

            JL222

[thommysgarage]

Thanks for the ideas. I like the idea of a NACA duct in the window, should be fairly easy and effective.

[Rex Schimmer]

BR,
I find it interesting that you will go to all of the work to weld up a special tube from the front with fittings and mounts etc and won't take an hour to make your own NACA duct. A small piece of 3003 aluminum, a pair of tin snips and your TIG welder is all you need. You can get the dimensions for the duct off the internet. Sure looks easier than a plumbing job.

Rex

[SteveM]

This is something that I wasn't able to determine from the rulebook - are fresh air vents REQUIRED for doorslammers?  I think I can graft some lexan NACA ducts to the side windows.

Steve.

[Tman]

This is something that I wasn't able to determine from the rulebook - are fresh air vents REQUIRED for doorslammers?  I think I can graft some lexan NACA ducts to the side windows.

Steve.

Steve, try these guys

https://www.pegasusautoracing.com/productselection.asp?Product=3627

[Rex Schimmer]

Steve,
If you use the "commercial" lexan NACA ducts you need to mount them on the inside of the window and make a cut-out in the window to match the duct shape. Most of the NACA ducts you buy have radiused edges and that interferes with the way the duct was intended to work. The edge along the sides needs to be sharp and square which you can make on your window, and the other thing is that the upper edge at the back of the duct needs to have a very generous radius on it.

Rex

[wheelrdealer]

BR,
I find it interesting that you will go to all of the work to weld up a special tube from the front with fittings and mounts etc and won't take an hour to make your own NACA duct. A small piece of 3003 aluminum, a pair of tin snips and your TIG welder is all you need. You can get the dimensions for the duct off the internet. Sure looks easier than a plumbing job.

Rex

Rex:

You are right again. I could fab a NACA. But I was looking for a plastic one to fit in the window and did not think about a metal NACA. Again, I want some postivie pressure in the car but not too much air volume becuase of the frameless windows. They will push out if too much air is entering the car. So a NACA with a 1" to 1 1/2" discharge tube would be perfect. I could fab one, paint is flat black attach it to the window with some SS #8 counter sinks and you would never notice it. Sometimes I just forget to remember things!

Thanks,

Bill

[Tman]

Listen to Rex, most of the off the shelf ones have the wrong profiles, the one I posted included. But, for a window issue they have proven to work allright in many forms of racing. That said, fabbed is always cooler than store bought!

[SteveM]

Steve,
If you use the "commercial" lexan NACA ducts you need to mount them on the inside of the window and make a cut-out in the window to match the duct shape. Most of the NACA ducts you buy have radiused edges and that interferes with the way the duct was intended to work. The edge along the sides needs to be sharp and square which you can make on your window, and the other thing is that the upper edge at the back of the duct needs to have a very generous radius on it.

Rex

Thanks Rex.  That approach is pretty much what I envisioned, but I didn't know those details regarding the sharpness and squareness of the transitions, along with the radius on the "back" of the duct.  Thank you for sharing your knowledge.

I was thinking of using some of the commercially availalbe NACA ducts, attaching 1 or more to the inside of the passenger's side door window by some combination of adhesive, pop rivets and/or bolts and nuts.

Steve

[Stainless1]

Most off the shelf NACA don't work, they must be for looks, if you buy one, test it before you waste a lot of time.
to test your duct, blow air parallel to the panel, put your hand in front of and then behind the duct and check for air, then check duct output...

If you want it to work correctly make it look like this....

[Tman]

I think I got this link from someone here? NACA Design

http://www.recumbents.com/wisil/nacaduct/naca-duct.htm

deals with recumbent bikes but is a good read.