Wind911

My understanding is that they redirect the turbulent air from the front tires out to the sides so there will be cleaner air to feed the rear diffuser. Since the 997 doesn't even have an engine undertray much less a rear diffuser, these parts have little use on our cars.

Wonderdan

I’m going to attempt to spread some fake news from the obsession I had with this a few weeks ago. I found that the drag coefficient of the 997.2 RS and 991.2 were both .33 and a tad higher at .34 for the 991.2 RS, strakes were responsible for .004 of that. So the strakes are to intentionally diffuse air to the sides and reduce turbulence under the car, but not for the reasons we think “meaning they don’t increase lap times”. They are primarily to reduce the gCO2/mile coasting drag numbers for EU efficiencies… which I’m only to guess is why the GT500 and other US built monsters not sold in the EU don’t have them.

Again… I have no idea what I’m talking about, I just regurgitate google.

GTTommy

Difficult to answer with no data but as an aero engineer my assumption would be...

​​​​​Obviously they remove some of the air from beneath the car which is always an advantage but my technical thoughts are, the air they direct will create an air curtain along the sill lower sill / door area which helps stop high pressure air sliding under the car at speed I.e. Increasing lift.

Similar to fitting blade style side skirts, they don't necessarily add downforce they just reduce lift.

Ultimately, there physically has to be an advantage to them, we'll never know exactly what, unless someone has a cfd model and we can add them in, my strategy was to do some laps before and after, more stability = win, for 100 dollars I don't think you can loose, assuming they fit.

Plan B is get some 3d printed to fit...
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