Plastic quarter window

Gregf

New member
In looking over a customers ITS car for a race weekend the question came up regarding a replacement rear quarter window that was used to install a Naca duct for driver cooling. One of our newer racers said it is not allowed in the rules but I clearly remember it being in Fastrack that one window could be replaced for the purpose of driver cooling. Where did this go? Greg F
 
In Spec Miata you may replace the vent window for this purpose, but to my knowledge there is no such allowance for what you describe in IT.

That said, with both front door windows either down or removed, it should be pretty easy to draw cool air for the driver.
 
I concur with Gregg. What you read was for Spec Miata; not allowed to replace the quarter in IT.
 
'Rear' quarter window? What kind of car? Are we sure this is a Miata?

And IIRC, the rules for this type of replacement DO exist for IT (front quarter).
 
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'Rear' quarter window? What kind of car? Are we sure this is a Miata?
He didn't say it was a Miata, he said it was an ITS car.

And IIRC, the rules for this type of replacement DO exist for IT.
"Quarter window", Andy? As in the rear window on a 2-door car? Ain't sayin' it's not there, but you'll need to cite that in the regs...
 
Section 9.i, mentions driver/passenger window area can have ducting added. No mention of replacing glass with plastic. I have seen NACA ducts positioned in line with the plane of the open drivers or passenger window to capture air into a hose that is routed to the driver.
 
"Ducting may be added to provide fresh air to the driver/
passenger compartment. This ducting shall be located in the
driver and/or passenger window area, with no modifications
to the bodywork. Only the cooling duct is permitted in the
window area. It is not permitted to otherwise fill in the window
area. The complete duct assembly in the plane of the window
shall be no larger than 100 square inches."

So I would submit that a window in the drivers compartment can be replaced with a plastic NACA duct set-up provided it does not exceed 100sq inches.
 
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Section 9.i, mentions driver/passenger window area can have ducting added. No mention of replacing glass with plastic. I have seen NACA ducts positioned in line with the plane of the open drivers or passenger window to capture air into a hose that is routed to the driver.

...but it allows that duct assembly an area in the plane of the window of up to 100 sq in.

K
 
"Ducting may be added to provide fresh air to the driver/
passenger compartment. This ducting shall be located in the
driver and/or passenger window area, with no modifications
to the bodywork. Only the cooling duct is permitted in the
window area. It is not permitted to otherwise fill in the window
area. The complete duct assembly in the plane of the window
shall be no larger than 100 square inches."

So I would submit that a window in the drivers compartment can be replaced with a plastic NACA duct set-up provided it does not exceed 100sq inches.

Don't think driver/passenger window equates to drivers compartment.
 
So I would submit that a window in the drivers compartment can be replaced with a plastic NACA duct set-up provided it does not exceed 100sq inches.
That reg is referring to the door window area only, not the quarter glass. Its intent is allow ducting while limiting one's one's ability to one, block off the window for aero improvements and two, minimize obstructions for safety workers getting to you through the window in case of incident (thus the "It is not permitted to otherwise fill in the window area" notation.)

Further, a quarter glass is not a "driver and/or passenger window area". By definition, a quarter glass cannot ever be a "driver window area".

Thus, this reg does not allow a quarter glass to be replaced/modified. If it did, then a lot of people would be dropping some weight off of head height be replacing the quarter glass(es) with Lexan and putting in a crappy ineffective "ducts". I certainly would.

GA
 
Im with Andy on this. It says the driver pasenger window. Dosent say Driver passenger FRONT DOOR window. On a 2 door,2 seater such as an RX7,the entire campartment is for the driver/passenger. NO? There is no back seat, no rear doors, no trunk area so to speak. Dont start preachin about spirits and all, I dont believe in ghosts.

As long as the window dosent take up 100 square inches then replace it with the allowed duct.

RX7 Quarter windows are about 100 square inches and I need to replace one HMMMMMMM

But then again, I like to argue about rules and such

Dan
 
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Dont be that way Greg, I said up to the total 100 squre inches, not all the glass in the car. The rear deck glass needs to stay. If the door glass is already removed, whats the point. We are only talking about the rear side glass on certain cars, that have windows smaller then 10 x 10. Thats not that big in all reality.

And besides, I am trying to save a couple bucks finding a 30 year old window is all.

Just laugh a little, Race Seriously, Dont take it Seriously, we are only racing for ashtrays.
 
Just laugh a little, Race Seriously, Dont take it Seriously, we are only racing for ashtrays.
But then again, I like to argue about rules and such

Just sayin.... ;)

Dont be that way Greg, I said up to the total 100 squre inches, not all the glass in the car.
So you're only going to allow users with rear quarter glass smaller than 100 sq-in the ability to replace that glass with polycarbonate? Seems a bit inequitable...and if the regs were not intended to allow placement of a duct soley in an already-vacant area (such as the allowed front door glass removal), then where in the regs does it say you can replace any glass glass with poly to install that duct? Can that replacement also extend into the rear hatch/window glass? After all, to your definition that's "driver/passenger glass", too...?

If the door glass is already removed, whats the point.
Ding! Winner. Quarter glass is not allowed to be removed by the regs. Thus there's no vacant space to fill with a 100 sq-in duct.

Just to ensure we're talking about the same thing, "quarter glass" is the piece below above the "Acura Motorsports" decal. I'm NOT talking about a rear door glass on a four door, I'm talking about a fixed piece of glass behind any door glass but in front of the rear hatch/window:

IMG_0497.jpg
 
We are talking about the same glass. And I dont really think that there is a car out there that uses on 10x 10 windows in the rear. Oh wait, my 87 Buick Regal had one that size. But thats not an IT car.

I just measured the 7 window. It comes to just over 100 square inches. And thats not a big window. Dam Need to find a piece of glass. Got any laying around I can duct tape into the hole?

Later dude, Your 7 awaits you. Come wrestle a dinosaur

You just had to get your car in this didnt you.
 
Later dude, Your 7 awaits you. Come wrestle a dinosaur...You just had to get your car in this didnt you.
;) Hey, if you'd stop wrecking yours we could use it as an example (and you'd have more pieces of glass!) I do believe there's a Regional at NHMS in April... - GA
 
Thanks for all f the replies. This car and several others were built by us from 2000 to 2006. ( Porsche 944) I am sure there was an allowance in SS or maybe T class cars to allow this. The car in question has a driver with MS, so it is part of an involved driver cooling system to control his core temperature. As I remember it it only allowed one window to be substituted, and only for the purpose of cooling the driver. Tjhis and several other items recently have cropped up as Fastrack allowances that have not made it into the final rules apparently. Greg
 
FWIW, I concur with the interpretation that the "duct" rule allows us to fill in some of the space vacated by the driver's/passenger's windows being down (or removed) but that there's no allowance for removal of any other windows. That was on the list of final tweaks that Pablo was going to get before the ARRC this year. :(

K
 
That reg is referring to the door window area only, not the quarter glass. Its intent is allow ducting while limiting one's one's ability to one, block off the window for aero improvements and two, minimize obstructions for safety workers getting to you through the window in case of incident (thus the "It is not permitted to otherwise fill in the window area" notation.)

Further, a quarter glass is not a "driver and/or passenger window area". By definition, a quarter glass cannot ever be a "driver window area".

Thus, this reg does not allow a quarter glass to be replaced/modified. If it did, then a lot of people would be dropping some weight off of head height be replacing the quarter glass(es) with Lexan and putting in a crappy ineffective "ducts". I certainly would.

GA

So being on the committee when this was written I certainly understand the intent. But I am not sure you can pin down the definition of "passenger window area". I would think it legal for a 4-door to cut a 10x10 chunk out of the rear door glass to install a duct.

I guess the real question is whether or not we consider this rear quarter glass part of the passenger compartment. As the 944 is a 4 seater, that RQG is, IMHO, passenger glass. I would have no issues with anyone cutting that RQG to install a legally sized duct for driver ventalation. Nit picking the wording for sure but I don't think it provides an advantage either way.
 
So being on the committee when this was written I certainly understand the intent. But I am not sure you can pin down the definition of "passenger window area". I would think it legal for a 4-door to cut a 10x10 chunk out of the rear door glass to install a duct.

I guess the real question is whether or not we consider this rear quarter glass part of the passenger compartment. As the 944 is a 4 seater, that RQG is, IMHO, passenger glass. I would have no issues with anyone cutting that RQG to install a legally sized duct for driver ventalation. Nit picking the wording for sure but I don't think it provides an advantage either way.

I've been contemplating just this very thing on the Mustang. I have some tiny rear quarters that would accommodate a NACA duct perfectly to feed my DR COOL.

"This ducting shall be located in the
driver and/or passenger window area"

My car carried passengers, and, the rear window is located in the passenger area.

Now, I know what they meant with the rule, but I think I could pass muster with a NACA duct in the rear quarter.
 
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