bkovac

I want to install a koolbox helmet cooler, where is it legal to mount a naca duct on a spec boxster? I was told the rear lexan is a no no. Hope someone can point me to a solution.

trygve

I saw a rear lexan naca duct last weekend on a SPB. Also wondering what to do if I get a helmet blower. Let us know if you find out more.

What with recent discussions about whether intake scoops are allowed, I wonder if the same logic would imply that naca ducts are similarly allowed. I always thought that all this kind of stuff (changes to bodywork not specifically called out) was illegal.

bkovac

Hello Trygve, it's Branimir. I hope your well and your cars all fixed up after FOS. I ask PCA about placing it in the rear window and was informed it would not comply with the rules.

Coloradoheel

What about cutting hole in the roof skin (where a rear quarter window would be in a coupe)?

bkovac

that was my original idea, but pca rejected that idea due to aero along with the rear window option. I was hoping to hear what others have done and passed scrutineering. Thanks for your response

Gary R.

In my 911 I simply tied the hose to the cage by the passenger window opening, worked fine. Doesn't need forced air, that's what the blower fan is for.

Coloradoheel

I run air to my Stilo. Not being able to get an answer about NACA duct, I routed the intake hose so it is grabbing fresh air from passenger "window"
It works well enough.

mmuller

I do the same. I am sure there is an aero impact if it pokes out however, no idea how much though.

The rule book is actually pretty clear where intakes or NACA ducts are permitted.