[paradoxical3]

Over on N54tech, I was discussing trap speeds for drag racing in a thread. I mentioned how my X1 was at 12.1 @ 111.2mph where one of the BMS cars was at 12.2 @ 115mph, which is due to the better traction of the AWD. The BMS car has significantly more power according to the trap speed, but I still win in the ET because I get a better launch.

Terry made a comment that the X1 being a brick was probably killing me at higher speeds. At first I agreed, but then I did some research:

BMW X1 drag coefficient: .32
BMW X1 frontal area: 2.34 sq.m

BMW 335i drag coefficient: .30
BMW 335i frontal area: 2.17 sq.m

In other words, the BMW 335i only has 1.8 square feet less frontal area than the X1. Keep in mind this may change for the M-Sport versions, I could not find published specs for the M-Sport kits.

With that info, we can compute lost horsepower at a particular mph.

At 100mph, the X1 has a power loss of 53.7 horsepower. The 335 would have a power loss of 46.7 horsepower.

The upshot? The X1 is aerodynamic enough where the difference between it and the 335i at 100mph is only 7 horsepower. Less than an intake. The faster you go the worse it gets, but even at 130mph it's about a 16hp difference.

Okay, that's impressive. But the 335i is a tremendously well designed car from an aerodynamic standpoint. Let's stack the X1 up against some American muscle - the 2012 Boss 302 Mustang:

BMW X1 drag coefficient: .32
BMW X1 frontal area: 2.34 sq.m

Boss 302 drag coefficient: .36
Boss 302 frontal area: 2.248

HP loss @ 100mph for the X1: 53.7
HP loss @ 100mph for the Boss: 58.1

The X1 actually GAINS horsepower on the Boss the higher the speed. This may be one reason why the X1 is punching so far above it's weight at the drag strip and in roll races. Power is just one component of speed.

Not too bad for a suv.