I'm planning my first overland vehicle build. I have a Subaru XV Hybrid which gets great gas mileage, but I want to add a 2" lift and replace the bumper for a better approach angle. With all of my mods, I will be considering weight and drag for highway driving. While almost any modification to the stock bumper will increase aerodynamic drag, I think the greatest impact comes from exposing the front of the tires, since they spin and create lots of turbulence.
My idea is to build a plate style bumper with some kind of flaps that can hinge down for highway driving. These flaps don't need to be particularly strong, since their only purpose is an air deflector. Before I start designing this in Sketchup, I wanted to ask if anyone has ever seen such a thing. When I get off-road, I will fold the flaps up out of the way or maybe remove them.
My last car was a Toyota Yaris, and I increased fuel economy 2% by building a smooth belly pan out of coroplast (plastic). It lasted for 2 years. I think that for the Subaru, aluminum skid plates can have a similar effect if designed well.
My idea is to build a plate style bumper with some kind of flaps that can hinge down for highway driving. These flaps don't need to be particularly strong, since their only purpose is an air deflector. Before I start designing this in Sketchup, I wanted to ask if anyone has ever seen such a thing. When I get off-road, I will fold the flaps up out of the way or maybe remove them.
My last car was a Toyota Yaris, and I increased fuel economy 2% by building a smooth belly pan out of coroplast (plastic). It lasted for 2 years. I think that for the Subaru, aluminum skid plates can have a similar effect if designed well.
