Help designing a wind fairing for roof rack

[Whitson Metalworks]

I like my big fairing, its growing on me and looks great with the bedliner. Someday I'll have time for version 2.0 but it just works so good its easy to put off. Mine is closer to the roof than wasted's but is pretty much the same shape.

 

[WastedAccount]

I didn't want it to close to the roof. I was afraid it'd flap and scratch the roof.

 

[Arv]

Thanks for chiming in, maybe this will be the basis of your 2.0!

 

[Whitson Metalworks]

Mine hasn't budged and the bottom is maybe 1/4" off the roof, in my mind's wind tunnel, it made for a smoother transition from the windshield to the fairing.

 

[Arv]

It hasn't given me back any gas mileage though. QUOTE]

Wasted,
Just to clarify did you mean the fairing did not help with the gas mileage that you lost when you installed the rack?
Just curious what mileage were you getting before and after.
I get like 16 mixed driving with the stock the crossbars.

 

[Arv]

Mine hasn't budged and the bottom is maybe 1/4" off the roof, in my mind's wind tunnel, it made for a smoother transition from the windshield to the fairing.

Smoother transition is what I have in mind too that's why I wanted to match the curve of the windsheild. Now wether the curved shaped fairing would actually help is the big question. But hopefully it would look good!

 

[WastedAccount]

I lost 1 to 2 mpg with rack on the highway. The fairing did not give those mpgs back. It did help with noise though. I driver fast but if I can keep it smooth I can get almost 17mpg on my 90 mile highway drives.

 

[Arv]

I lost 1 to 2 mpg with rack on the highway. The fairing did not give those mpgs back. It did help with noise though. I driver fast but if I can keep it smooth I can get almost 17mpg on my 90 mile highway drives.

Based on your mileage figures it looks like a full fairing does not drop your mileage further with a Whitson full roof rack. And wind noise is definitely less.

Now what I want (or dreaming of) is to find the balance (which will probably not happen) where the fairing configuration will actually increase the mileage and reduce wind noise at the same time. Not sure at this time whether the amount of gas you save or noise reduction is more important, but I'll take either advantage as long as its an increase in both.

 

[ktom3001]

Based on your mileage figures it looks like a full fairing does not drop your mileage further with a Whitson full roof rack. And wind noise is definitely less.

Now what I want (or dreaming of) is to find the balance (which will probably not happen) where the fairing configuration will actually increase the mileage and reduce wind noise at the same time. Not sure at this time whether the amount of gas you save or noise reduction is more important, but I'll take either advantage as long as its an increase in both.

Sorry to crash the 3rd gen board and revive an old thread but there seems to be a bit more interest over here in racks/fairings. What did you end up with and how did it work? See link below to the 4th Gen thread I created, not much feedback from those guys. Feel free to reply on this thread instead if you prefer.

http://www.toyota-4runner.org/4th-gen-t4rs/157661-roof-rack-fairing-design.html