Here is how I have had the air intake duct on my last two cars. It is easy to put the naca duct in the upper left corner of the passenger side with a few rivets and I think that is very similar to what you would get if you put it in a lexan window in the rear passenger window. I also like this location better that in the lower front corner of the front window because this configuration doesn't interfere with using a passenger seat. I did cut the duct down to provide more clearance for a passenger. This is such an easy solution I don't know why more people aren't' doing it this way. It is definitely cheaper and easier that doing a lexan window insert.

Dean, I am one of the guys that was NOT supportive of your suggestion of Lexan quarter windows.

I WAS WRONG. I had not given enough consideration to the safety concerns, especially as it relates to the fire and smoke issue from a bad situation. I have raced in the Arizona region and Tage has done a wonderful job with turning that region's program around. His incident was, quite simply, shocking to me and made me realize just how dangerous our sport can be. I know that I get complacent because most of the time we are very safe.

Steve, thank you for posting the pictures of how you did your duct system. I was having a hard time understanding what your approach was until I looked at your pictures. As they say, 1 picture is worth ...... My only concern with what you did, Steve, is my new found concern for smoke/fire coming along the left side of the car that could get into the intake. My reason is simply that our fuel rail, oil filter and oil coolers are on the left side where the exhaust system provides a ready source of ignition and the potential of smoke/fire along that whole side of the car. If that were to occur, even having the intake inside the car is going to suck smoke into the system because smoke will come in the passenger side window for sure.

Eric, I was never able to see your pictures.

I am going to look at trying to do something like Steve did but on the left (drivers) side door. The window net will be an issue but I will see what I can do with it. Short of that working, the only other solutions are the drivers quarter window or cutting into the sheet metal to put a duct or scoop to supply outside air. I am not of the opinion that using inside air is an acceptable solution for all the reasons I have discussed both in this post and prior ones in this thread. I see using the left side for fresh air as being the best choice for our cars because all of the nasty stuff is on the right side of the engine (unlike the typical V6 or V8).

As for Nor Cal, if you can guarantee that Thunderhill NEVER gets above 76, I will be your newest Nor Cal region member. I like the idea of the gold track but wonder how the traction is. Of course, with the tire situation, low grip should make the tires last much longer.

Jim

Big Dog wrote:


Jim I don't see the left side as a fire risk. At least not way up high at the top of passenger window. Fire would start under the car and as Eric's pictures show at speed the flames are pulled under the car and out the back. Once at the back of the car the natural turbulence will cause these flames to move up the back of the car. In Tage's case the flames got sucked/pushed into the open back wiindow. The reason is simple aero dynamics and the way turbulence comes off the top of the car and underside.

In our case the rear hatch will not allow for that much rear air flow in to the car. The two door windows are pretty far away and for the flames to enter the car there through them the entire front end needs to have flames coming out from hood area through the fire wall on to the windshield. Fire like that is extremely bad and alot of flame would be entering from the open windows on both sides of the car.

I see Steve's solution as a perfect way to get fresh air that is totally in the rules and does not create any rules creep either.

Big Dog, I forgive you....

Steve, installation looks very nice!