So I'm working on a fairing design to cope with my decreased mileage and I was interested in input. I'm down around 3 MPG (highway) but I can't attribute that all to the rack. I also installed 255/70/18's at the same time (still tweaking PSI), and the weather out here has been very cold which is also contributing to mileage decline. The only one of the three in my control at this point is the fairing so I'm looking at options.
Version 1 (first pic) was a simple rack "face" only fairing. It worked ok but wind noise was still pretty bad and mileage sucked. Though we were loaded for a trip and it was very windy too.
Version 2 goes all the way to the roof. Though the angle is not matched to the windshield, it's probably a 15 degree mismatch. This version is way quieter but there is a dead spot that seems to want to suck the sunroof upward. Mileage hasn't really improved significantly over V1.
So here are the questions
1. Is the V2 fairing just too big? Should I trim down the sides/bottom a bit?
2. Is the angle mismatch (Fairing VS windshield) a huge issue? Causing the dead spot over the sunroof? Would the sunroof rack insert help this? What about a two piece fairing that extends slightly back flat over the sunroof opening?
3. Is the Gobi fairing that only goes slightly over the bottom bar a better design? I guess this would be determined by what's causing more drag/noise, fairing or roof rack?
4. Has anyone experimented with a textured or dimpled aluminum material to break up the airflow like a golf ball? It wouldn't be that difficult or expensive to have a sheet made, though experimentation with patterns and size would be cost prohibitive. What about a heavily textured paint?
Hope this isn't too many questions. Maybe there's an aero engineer in our midst?
Version 1 (first pic) was a simple rack "face" only fairing. It worked ok but wind noise was still pretty bad and mileage sucked. Though we were loaded for a trip and it was very windy too.
Version 2 goes all the way to the roof. Though the angle is not matched to the windshield, it's probably a 15 degree mismatch. This version is way quieter but there is a dead spot that seems to want to suck the sunroof upward. Mileage hasn't really improved significantly over V1.
So here are the questions
1. Is the V2 fairing just too big? Should I trim down the sides/bottom a bit?
2. Is the angle mismatch (Fairing VS windshield) a huge issue? Causing the dead spot over the sunroof? Would the sunroof rack insert help this? What about a two piece fairing that extends slightly back flat over the sunroof opening?
3. Is the Gobi fairing that only goes slightly over the bottom bar a better design? I guess this would be determined by what's causing more drag/noise, fairing or roof rack?
4. Has anyone experimented with a textured or dimpled aluminum material to break up the airflow like a golf ball? It wouldn't be that difficult or expensive to have a sheet made, though experimentation with patterns and size would be cost prohibitive. What about a heavily textured paint?
Hope this isn't too many questions. Maybe there's an aero engineer in our midst?
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