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4 Enhancements STI made to make the 2015 WRX STI NBR faster

The new 2015 Subaru WRX STI NBR race car is getting ready for the Nurburgring 24-hour race. What changes did STI make with this new car?


The new 2015 Subaru WRX STI NBR gets a number of enhancements and many include body changes that make the sedan more aerodynamic. STI is hoping for faster lap times and less pit stops because the car will be slippier and more fuel efficient. Will these two factors help Subaru win at the Nurburgring 24-hour race in May?

STI says they wanted to change the aerodynamics of the new 2015 STI NBR to obtain the necessary downforce in the north course of the tortuous Nurburgring "Nordschleife". They also need to account for the long straight and high speeds in the other sections of the race. The testing they are doing at the Fuji Heavy Industries (FHI) wind tunnel will be part of the process it takes to determine the necessary aerodynamic setup.

CHECK OUT: New WRX STI NBR undergoes experimental wind tunnel test

Changes made to the STI NBR

To do this, STI had to move the rear wing to the farthest rearward mounting position permitted by regulations. This will give the car the desired downforce at the rear of the car. They also made adjustments to the front under spoiler and canard that affects the amount of lift generated to the front end. The third thing STI did was to reduce the resistance of air flowing through the sides of the vehicle body by changing the front and rear fender shape.

STI uses computational fluid dynamics

Lastly, STI reduced the air resistance through the engine intracameral to the desired amount. All the changes were calculated using the CFD (computational fluid dynamics) analysis tools at the FHI facility. The shape of the new STI NBR was as close to ideal before the car was put in the wind tunnel. After the bodywork was done on the actual vehicle, it was put in the wind tunnel for final testing.

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The final tweaks will be made after they ship the car to Germany for actual testing on the Nurburgring Nordschleife. STI is counting on the new 2015 Subaru WRX STI NBR to be faster and more fuel-efficient than last years car. Subaru will run the new STI NBR in the Nurburgring 24-Hour race this year on May 14-17 in Germany. Stay tuned.


Daren (not verified)    March 7, 2015 - 7:48AM

As an owner of a 2015 WRX; I think the profile of the NBR is more proportional overall and it looks fantastic! I hope the production mid-model refresh takes on this look; with a new or enhanced engine for the Sti to match the new Focus RS. I will be again first in-line to get one.