,
I made the ‘cut’ a bit narrower than the snorkel along with placing it a bit forward. Remember, you can always cut more material, but you can’t add it back.
With the first cut made, I used some more C.A.D to get the slope of the hood.
Next, I made another cut and some more cardboard to get the slope of the hood in the fore-aft direction.
With the two pieces of cardboard, some engineering paper, and some calipers, I had the slope of the hood.
Plug in the main values into the handy dandy spreadsheet….
Do a little 3D modeling…
And voila! (A good chunk of change later…) A rapid prototyped NACA duct out of PC-ABS. Now, I needed to make the big cut in the hood. I used some more paper and a pen to get the outline of the opening of the duct.
7 comments
Hey Moto IQ , first thing you guys are the one of the best at building track cars and I love all of your upcoming projects. Im in need a a NACA vent for my 2011 BMW 335i and this vent looks perfect. By any chance can you guys get another one made and I will pay before its even made, really need this vent.
guys are one of***
Appreciate the comment! This NACA duct was designed specifically for the S2000 hood shape and airbox location. For your needs, you can probably go with something generic? Pegasus Auto Racing Supplies has some NACA ducts that could work.
Would the NACA duct have water issue when it rains? I’m also looking for a brake duct kit for an AP2 that comes with the dust shields already with the hole for easier installation. WASP Composite seems to be the only one that made such a kit with the hole directed towards the center of the rotor as it should be. Unfortunately it doesn’t seem like they sell the kit anymore. Any ideas/recommendations? Many thanks!
Personally, I wouldn’t use the NACA duct in the rain. I’m not sure the stock airbox has any water drainage provision. It’s easy to swap hoods, so I only put on the track hood for the track.
As for brakes, if you track, I’m a huge proponent of going straight to the StopTech BBK. Of course, that means you need new wheels to clear the brakes. If you want to keep the stock brakes, you could just remove the dust shields. I haven’t had the dust shields o the S2k in ages and I went around 100k miles on my old Nissan without dust shields. You will need to figure out a way to mount the end of the hose. I just zip-tied it before.
https://motoiq.com/project-s2000-part-4-taking-it-to-the-track/3/
Are you selling these?
No, I only made the one. If you decide to go this route, you should also stick a one-way check valve in the air hose going from the intake to the front breather on the valve cover. I was losing ram air boost through this flow path. I regained the lost boost after plugging it in later testing. A one-way valve is a more elegant solution.
https://motoiq.com/project-s2000-part-22-testing-new-goods-and-more-intake-mods/2/