Bimmerfest - BMW Forums - View Single Post - The two lil flaps right in front of the front tires
View Single Post
Old 03-21-2011, 03:57 AM
Marlbro's Avatar
Marlbro Marlbro is offline
UK (ex-Pat)
Location: Limburg, Belgium
Join Date: May 2010
Posts: 336
Mein Auto: 2010 X5 3.0d M pack
Originally Posted by 0428 View Post
I believe you. But also I believe "if you were to cut them off, you probably wouldn't notice the difference". Then so what's the point?

In racing, where every little bit counts, why dont you see these flaps on race cars, or high end car like Lambos or Astons?
Well, as I said, they are developed in wind Tunnels, and as with all "Labratory" developments
you can show minor gains here and there, and convince people that they are worth it.

BMW prouds itself on having developed the "Air cushion" it calls it.
I was reading in last months BMW magazine (the one with the new X3 on it)
how by developing the outer body styling, that feature line that runs from the front wheel arch, rearwards, and blends out towards the rear. By developing air flow around the front end, past the tyres, they can build up this "Air cushion" that helps to clean up air flow past the car, and in so doing so also help fuel economy.

Now all that might be true in an Air Tunnel, but in choppy cross winds driving past trees, and trucks on the high way, I doubt how much affect that would really have.

racing cars are a whole different kettle of fish, Much lower to the ground, the front Spoiler splitter (that flat piece) sticking out of the front Spoiler is there to "Split" air flow, and push most of it over the car, producing down force. the negative air flow under a very low car, with a flat bottom, will create a partial vacuum, sucking the car down. (at high speeds)

Why don't we have that on road cars,
well, how would you get over those speeds bumps in the Sears car park ?

Most lambos, Aston martins, and Ferraris, have front spoiler splitters, and an under tray with aVentury duct in it that exits at the rear, and usually, tey put the exhuast there too.
This has the affect of accelerating the air under the car, creating more down force, and as it exits, helps to suck the gases out of the exhaust.

Now as to the OP that said his X5 doesn't have these front flaps.
All Euro X5 & X6s I've sen have them, and also a lot of Euro cars have them.
But i did look at one used X6, when choosing my X5 where the last owner had broken one off.
How he did that I don't know (maybe off roading)

2010 X5 30d M Sport pack on 20 inch
In Space Grey, Panoramic roof, auto tailgate,
Privacy Glass, Comfort seats in Black?
Rear view camera
Reply With Quote