Sedan roof spoiler?

[RallyXLTZ]

Has anyone installed a rear roof spoiler/air diffuser on their sedan? I was thinking of either the STi's little spoiler or the Evo's diffuser (which would go well with the Sonic theme since it looks like spines). I was going to use one of those, then install a small trunk wing or maybe just leave it factory there. I don't want it to look ricer-ish or just have too much going on.

http://imgc.classistatic.com/cps/blnc/120823/810r1/1461jh6_20.jpeg

STi roof spoiler

http://www.vividracing.com/catalog/images/mrvortex.jpg

Evo air diffuser

What do you think?
-Kyle

 

[rdss]

I'm sure it wont look bad but it's not something I would do. I would probably go with the Evo spins, the STi one would probably be hard to fit to the Sonic and is kind of bulky looking for a small car.

 

[RallyXLTZ]

True. I was leaning toward the Evo style anyways

-Kyle

 

[RallyXLTZ]

Just saw that Tapatalk has both of my links posted as smileys, or at least on my screen. Did they post right on the regular forum or everyone elses app?

-Kyle

 

[Dlowwoc]

Ive had these on for awhile. It was a real pain in the arse to get the proper angles for each fin. I like the look and have received maybe 0.5 mpg more by my estimation.

 

[RallyXLTZ]

I really like that! Did you have to fab that yourself, or cut an Evo spoiler to do it?

-Kyle

 

[ThatTmoGuy]

I've always like the STI roof spoiler, if it was a littler lower profile i think it would work well with the Sonics design.

 

[Bogus]

What do those do?

 

[RallyXLTZ]

They help keep air pressure and down force going on the car. Helps keep it grounded at higher speeds. Aerodynamics, my friend!

-Kyle

 

[Dlowwoc]

I really like that! Did you have to fab that yourself, or cut an Evo spoiler to do it?

-Kyle

Got them from Ebay.
vortex generator in Car & Truck Parts | eBay

They stick on. The hard part is getting each one to the right angle.

Here's mitsubishi's research paper on setup and effectiveness.
http://www.mitsubishi-motors.com/corporate/about_us/technology/review/e/pdf/2004/16E_03.pdf

 

[firstorbit84]

They help keep air pressure and down force going on the car. Helps keep it grounded at higher speeds. Aerodynamics, my friend!

-Kyle

Well, not exactly. In the case of the Evo, they direct more air into the high rear spoiler, which increases downforce (very minimally and at very high speeds).

Without the high rear spoiler they are reducing turbulence from separation at the roof line and will just reduce drag and have a small increase in mpg at highway speeds.

Ideally, you'd want to place them on the trunk lid for a greater effect.

I'd also personally go with a more effective design like these: http://www.airtab.com/main.html

 

[RallyXLTZ]

Well, not exactly. In the case of the Evo, they direct more air into the high rear spoiler, which increases downforce (very minimally and at very high speeds).

Without the high rear spoiler they are reducing turbulence from separation at the roof line and will just reduce drag and have a small increase in mpg at highway speeds.

Ideally, you'd want to place them on the trunk lid for a greater effect.

I'd also personally go with a more effective design like these: http://www.airtab.com/main.html

That's very true. I was trying to decide whether I wanted a deck lid spoiler as well, so I guess that bit of info made my mind up for me! I want to find something along the lines of the lower profile spoiler from the WRX and not the STi wing.

Got them from Ebay.
vortex generator in Car & Truck Parts | eBay

They stick on. The hard part is getting each one to the right angle.

Here's mitsubishi's research paper on setup and effectiveness.
http://www.mitsubishi-motors.com/corporate/about_us/technology/review/e/pdf/2004/16E_03.pdf

That's a good find! Thanks for the help brother!

-Kyle

 

[Dlowwoc]

Glad I could help.

I got the deck lid spoiler from carid in plasti-derp black.

http://i918.photobucket.com/albums/ad26/dlowwoc/Sonic/IMG219_zps6a039f42.jpg

 

[firstorbit84]

I've seen that Mitsubishi paper before. If you read the results, the vortex generators increase downforce and reduce drag coefficients by 0.006 at 111 mph. Hardly significant IMO

You can also see that most of the turbulence is behind the rear deck, not coming off the roof

 

[RallyXLTZ]

Yeah, I noticed that in the file also. Granted I won't hit that speed often enough to necessitate those pieces...I would still like to try it out. If it will help mpg and performance simultaneously it is worth it to me. Even as miniscule as that decimal is lol

-Kyle

 

[firstorbit84]

Remember, without the giant rear wing you will only get the drag reduction and no additional down force

 

[Super_Sonic94]

I had the exact idea, but i was thinking of putting something this on my rear window

 

[RallyXLTZ]

Remember, without the giant rear wing you will only get the drag reduction and no additional down force

Ehh...I don't even like the wing on the STi or Evolution lol. The drag reduction would at least help with mpg I guess.

I had the exact idea, but i was thinking of putting something this on my rear window

That looks good too. If there was an available part like that right now I would jump on it!

-Kyle

 

[Super_Sonic94]

What? i havnt found, shoot over a link, i think imma do some shoppin. haha

 

[RallyXLTZ]

Oh no, I was saying that I haven't been able to find that anywhere haha. I wish I could, though. Ebay has them for literally every car except ours.

-Kyle