Functional hood vents/louvers

Nosrok

Private
Jan 31, 2017
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I've seen some fender venting that supposedly helps get hot air out of the engine bay as well but haven't done much poking around that area of the engine bay to see if it would be beneficial for our cars.

After hitting limp mode at the track because of high temps I changed out the oil cooler valve and added a CSF radiator. the day it happened it was also a 95 degrees outside and like 105 or more on the track, car temps have been in line since but this summer will be another test.
 
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Davidwarren

Corporal
Nov 6, 2016
203
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Louisville
Have you removed your cowl? If so you should consider putting it back on, same with the under body trays. They help direct the air coming in through the grill, the cowl blocks air from pushing in near the windshield at higher speeds.

You could probably duct fresh air from the fog light area to that side. Also a few people have flipped the factory airbox scoops/duct to the other side and it seems to work.

As for vents you want them near the front so the air moving over the hood pulls the hot air out of the engine bay. Slightly behind the radiator is where I'm looking to place mine, very similar to one of the available hoods.
Totally agree. The base of the windshield is high pressure. That is why your vent intake is there. That is how cowl induction works. At speed, air is flowing into the bay at the cowl, not out.
 

screaminfast

Sergeant
Feb 18, 2017
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Rochester NY
mikecentola.com
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Been thinking of doing this myself. I have a painted carbon hood. However, I was thinking a single NACA duct right over my filters. Maybe a way to attach a door in the rain.

Came across this guy on fb.

3120E1E5-B70C-4109-927D-8746B16526B9.jpeg
 
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Team503

Lurker
Nov 21, 2016
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DFW
Why wouldn't you just buy a vented hood? There's a variety of designs out there and you can get FRP or carbon fiber as you prefer..
 

screaminfast

Sergeant
Feb 18, 2017
256
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Why wouldn't you just buy a vented hood? There's a variety of designs out there and you can get FRP or carbon fiber as you prefer..

I got my CF hood super cheap because it was damaged and I had it painted body color. So at least, speaking for me, I want to just add some louvers or a vent to what I currently have.
 

Dmak

Specialist
Nov 19, 2017
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09 bmw 135i
Why wouldn't you just buy a vented hood? There's a variety of designs out there and you can get FRP or carbon fiber as you prefer..

It comes down to price vs function. While a aftermarket hood is not overly expensive, shipping usually is(at least for me in canada) for such an item its also easily damaged during transport. Anyother problem would be the location of vents for best function. Almost all of those aftermarket hood are design for looks not really function and the vents are most likely not at the best location. Last would be price. I can get vents/louvers under 200bux. Only down side would be cutting the stock hood.
Theres also one big thing with aftermarket carbon hood is safety. I remember reading something about having a carbon hood and something to do with the fiber breaking and get into your skin or something. I will see if i can find some info about that.
 

fmorelli

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Aug 11, 2017
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The only other way to improve cooling vs factory system is really just have vents on hood. Factory ducting is already pretty well done. I will see how it fit with the factory air duct flip so air goes to the right side.
I always wonder about this - you have a major automotive company with arguably some of the deepest engineering chops, fluid dynamics guys, engineers of every flavor, cars designed in wind tunnels. When you take a modern BMW apart you see all kinds of attention to underbody details - things most customers never see or know they are paying for. Seems to me that it is easier to screw all that up than improve it.

Filippo
 

Dmak

Specialist
Nov 19, 2017
74
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09 bmw 135i
I always wonder about this - you have a major automotive company with arguably some of the deepest engineering chops, fluid dynamics guys, engineers of every flavor, cars designed in wind tunnels. When you take a modern BMW apart you see all kinds of attention to underbody details - things most customers never see or know they are paying for. Seems to me that it is easier to screw all that up than improve it.

Filippo

Yes. I have to agree bmw done a very good job for factory need.
And that is y i would like some feed back/info from people who have done it.
A basic fbo n54 is going to be running at least double the boost from factory. And then theres also the single turbo guys. While improving the cooling systems for coolant and oil are important. I would have to say reducing overall heat in the engine bay is also important. If it can be done cheaply with good result, why not?
 

screaminfast

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Feb 18, 2017
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Pre lci e90 has very limited options. M3 look or rice city look

Agreed which is why I went stock CF.

I always wonder about this - you have a major automotive company with arguably some of the deepest engineering chops, fluid dynamics guys, engineers of every flavor, cars designed in wind tunnels. When you take a modern BMW apart you see all kinds of attention to underbody details - things most customers never see or know they are paying for. Seems to me that it is easier to screw all that up than improve it.

Filippo

Absolutely. But remember everything is cost vs reward for major manufacturers, so there almost always is room for improvement.
 

BOosted 335i

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Jun 1, 2017
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New Jersey
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E90 BMW 335i
Is anyone worried about the rain when it goes through the vents from hood into engine bay onto the turbo(s).i would think that's a bad thing.im all for vented hood.i like the Vorsteiner v35 but sad they don't have a e90 version.but then again worry about getting the 1200 plus degree parts wet can shock/warp over time.
 
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