How to reduce drag of surfboard roof racks?

[Palionu]

Note from MetroMPG: this thread split off from Roof rack test: quantifying the aero penalty

Is it possible to decrease the drag on a roof rack? I'm a surfer and I own a 2001 Civic coupe so the roof rack isn't easy to take on/off. It uses some arms that I'm considering on streamlining.. Basically, this is my first post as a new member/former lurker.

I have a fairing but I want to get rid of it due to all the noise it makes, I thought of applying some of those tornado generators that you see on the Lancer Evo on the back of the roof. I also saw some aero bar fairings that I could trim to go on either side of my pads (I need the pads for my surfboard). I drive conservatively and average about 32-34mpg right now with the roof rack (epa is 29mpg) and I'm continuing on improving my hypermiler driving.

[MetroMPG]

Hey Palionu, welcome.

I'm going to guess that carrying the board(s) inside the car isn't workable, or you'd be doing it already.

Next, since you've decided to spend time on the problem, what I'd suggest is working out some kind of quick-release system for the crossbars, rather than leaving everything on the car & spending time trying to clean it all up.

If you could come up with a way to remove the crossbars, for example, it would be easier to fabricate some aero "caps" to streamline the remaining pylons.

Any chance of posting some pics of the situation?

Nice work on getting above the EPA numbers, btw.

[MetroMPG]

Originally Posted by Palionu

I thought of applying some of those tornado generators that you see on the Lancer Evo on the back of the roof.

Unfortunately, those won't work if the air ahead of them is already turbulent because of the roof racks.

Also - I suspect your car (without racks) has attached flow down the rear window - the Evo's rear glass is pretty steep compared to yours, which is why they put the VG "band-aids" on. (What year is the Civic?)

[Palionu]

Originally Posted by MetroMPG

Hey Palionu, welcome.

I'm going to guess that carrying the board(s) inside the car isn't workable, or you'd be doing it already.

Next, since you've decided to spend time on the problem, what I'd suggest is working out some kind of quick-release system for the crossbars, rather than leaving everything on the car & spending time trying to clean it all up.

If you could come up with a way to remove the crossbars, for example, it would be easier to fabricate some aero "caps" to streamline the remaining pylons.

Any chance of posting some pics of the situation?

Nice work on getting above the EPA numbers, btw.

I thought of cutting off the excess bar on each side and use some rounded plugs.

I've tried getting my board in my car but it's 10'6". I'm not at my home right now but I'll make sure to take some pictures. For now I can show you what I have installed.

While trying to find the link for the above picture I found a new mounting system but it will require me to drill 8 holes into my car roof. Eh, I'm probably going to drive it until it dies so this looks like a viable option and would certainly reduce drag over the above. Plus, it would allow my rack to be remove much more easily.

[MetroMPG]

Those mounts: I think we've found a winner! Anything you can do to get the rack off the roof more easily is a good idea.