Advice: Roof rack or hitch

[biketowork]

Claw, thanks for the picture. Honestly, I like the angle. Did you cut into your bumper to mount your hitch there. Do you have any pictures from below? I'd love to see how you did it.

 

At first I was thinking of picking up a Hidden Hitch, but still shopping around...if I can find a reasonably priced OEM hitch, I'd like to get it instead.

[ehsnils]

4 years in engineering school does this to you... Fd=(1/2)*p*Cd*A*v^2

 

If you add a roof rack, you're increasing the frontal area of the car by maybe 2-3 ft^2. Plus you're increasing your drag coefficient.

 

Now maybe that won't add up to 25% increase in Fd, but that's just the figure I overheard from a friend the other day.

 

And don't forget that the location of the rack is important. Due to the shape of the car the airflow is different at different positions around the car. This means that the impact can be greater or less than calculated when it comes to how much drag a certain object causes.

 

In some extreme cases you may actually get less drag when adding items to your car. There's a tale of a dude that made his own roof box and since he had no wind tunnel he took the car for a test run and when it was going faster with the box on than without it he was satisfied with the design!

[Claw]

Claw, thanks for the picture. Honestly, I like the angle. Did you cut into your bumper to mount your hitch there. Do you have any pictures from below? I'd love to see how you did it.

 

I pretty much followed this thread:

http://legacygt.com/forums/showthread.php/everything-you-wanted-know-hitch-install-12576p7.html?

 

If I remember, it's a DrawTite hitch, you have to drop the exhaust to mount it as it goes into a couple of screw holes above the mufflers. The intructions have you mount the hitch below the tow hook with a screw going (from top to bottom) into a washer, metal bar to support it over the hook, through the tow hook, into a slot on the hitch, then to another washer and finally a nut. Not sure if I can find my instructions.. I'll have a look.

 

I opted to install the hitch over the hook because I have a nice curb to get up my driveway to reduce the chances I'll scrape it - I'm lowered on iON HD springs in the back.

 

Because of my setup, I had to add a few spacers/washers at the mounting locations that connect the hitch to the chassis. It's pretty tight in there.. and I didn't use any hardware to secure the tow hook to the bracket - it sorta sits there.