Most Fuel Efficient Roof Box

Roof boxes fix to your roof racks either with a basic u bolt system or a claw style attachment.

Most fuel efficient roof box.

A former rolls royce aircraft engineer was hired to take yakima s racks to the next level and we have him to thank for the wispbar s wind cheating aerofoil wing profile. Promoted as the quietest most aerodynamic and fuel efficient line of roof racks in the world yakima s wispbar takes direct aim at conservation minded drivers. Bengt halvorson april 15 2015 comment now. For comparison the additional fuel consumption caused by roof racks is about six times larger than anticipated fuel savings from fuel cell vehicles and 40 percent of anticipated fuel savings.

Keep in mind that your car uses more fuel when it has a roof box attached our test car used 12 1 more fuel with the roof box fitted than without. The box has tapers to a point and employs diamond textured aero skin to help it slice through the air and protect vehicle fuel economy. A close second was the kayak with 28 percent or a. The gear with the most impact were the dual mountain bikes strapped to the roof which impacted the fuel economy by 31 percent or 9 mpg.

If you follow our coverage on fuel efficiency you know that real world mileage numbers don t always measure up to the official epa ratings.