[hillhucker]

I'm sure the aerodynamics of a 140mph beer keg are TOTALLY different than those of a 200mph cruise missile.

I will definitely check out that article here in a minute though...

haha...of course. I mean you definitely see better performance from aerodynamics at 100+ mph speeds, but i also did this mod to decrease under hood temperatures, which will decrease intake temperatures so i can have more consistent power output.

Even at normal highway speeds correct aero should play a role into the handling of your vehicle, and also the acceleration of your vehicle. If you can lose that under hood/car extra turbulent pressure to above/outside the vehicle, there will be less overall resistance by the vehicle. Another GREAT car to look at this on is the Ferrari Enzo...Amazing aero from ducting properly.

 

[hillhucker]

So i got the Genright louvers in...i bent them in to the shape of the fender and just have some scotch tape holding them on. I think i like the way they make the car look, but i'm not sure. They will definitely increase engine bay venting performance though. Tell me what you guys think.

 

[scoob r u]

Hmmm... Not a big fan actually.

I was thinking something like this would be kinda hot:

 

[hillhucker]

yeah, i'm not sold on the way they look yet. I couldn't do chrome on my subie.

 

[noob2sti]

I don't like either one especially the chrome ones. However you will be making a cosmetic sacrifice for better performance. Is it worth it? What type of racing will you be doing?

 

[hillhucker]

Just 1 or 2 track days a month, but i am wanting to reduce my under hood temps by as much as possible for better engine performance, plus higher speed handling. I am thinking of another modification to the rear fender vent, where i will cut/fab the top above the STi badge thing, and make it match the lower factory vent. This might be a better option.

 

[yositoco]

Your original idea of the bigger fender holes and remove the plastic flapper is great and I applaud you on it. With that said I think you are getting a little carried away and missed the bigger picture that you are about to mess your exterior of your car permanently for maybe a few less degrees under the hood. My .02 is DONT DO IT.

It;s a fine line between innovating and doing crazy things.

 

[scoob r u]

I agree that the pic I posted above would look better in carbon fiber or matte black... I just couldn't find a picture on short notice, and these were the style that I was thinking of.

 

[hillhucker]

I'm not too worried about messing up the exterior since fenders are not that expensive and it's just a body panel anyways. But i don't wanna do it if i'm just going to want to change it back to original a week later and dump 200-300 for a painted fender. Thanks for the input!

 

[ddcha]

I don't have that rubber block behind my fender vents. didn't ever have any on the car...

 

[hillhucker]

That's kinda strange...i guess your car was meant to be fast.

 

[ddcha]

That's kinda strange...i guess your car was meant to be fast.

What year's your car? Anyone else with an 08 that doesn't have that rubber part blocking the fender vents?

 

[hillhucker]

Mine's an 08 also.

 

[d3zi]

'08 here. 2nd owner of the car and I still have the rubber pieces.

are you the original owner ddcha?

 

[Tarmac_GR_STI]

Weird. Maybe they forgot to put yours on... wonder what else they forgot to put on...

 

[Fast Willy]

I don't really care for it. You would be better off buying a re extractor hood then putting those on your fenders. Putting holes in your fenders isn't going to reduce the temps by as much as you think.

 

[hillhucker]

hm...i just feel the top of the fenders after a solid drive and they are very warm. It seems if there's enough heat there to increase the temp of the metal that much of the fender, then it could definitely do some good to be evacuated. I didn't want to go for vents in the hood because of excess weathering to the engine components/wiring. I've seen quite a few race car that use top fender vents, like ALMS type cars used to a couple years back. But, you're probably right about it not decreasing the temps by that much. Thanks for your input!

 

[ddcha]

'08 here. 2nd owner of the car and I still have the rubber pieces.

are you the original owner ddcha?

I'm the second owner, but bought with 4k miles on it. bone stock.

 

[Fast Willy]

The fenders are partly hot because of the outside temps from the sun.

 

[Fly'n Brian]

Are those the Michelin racing slicks on the STi?