When installing the front brake ducts on my Evo, I was not (and am not) happy with the length of hose run and number of bends to get to the front end.

There are pics scattered in some other threads of different approaches to this issue. Please post any pics/info in this thread you would care to provide.

I am particularly interested in NACA ducts. Saw some pics where a Subie guy installed them in the undertray. How well does this work?

 

I've got mine on the back/bottom on my tray, work brilliantly. Too much effort to find all the pics I can remember, but keep looking they're there.

 

..

 

I have been searching for small lightweight 12 volt fans for cooling brakes. There are available 3" fans used by Trans Am and NASCAR. Most Trans Am cars will run Two 3" hoses to each hub with 1 of the hoses running through a fan.


http://cgi.ebay.com/Blower-fan-3-x-3...item255c79a4e4

We are using twin 2" hoses that would need an adapter to connect both 2" hoses to the 3" fan. I have looked at smaller light weight plastic computer server 12 volt blower fans but they only push 30-40 cfm.

 

https://www.evolutionm.net/forums/mo...e-ducting.html
https://www.evolutionm.net/forums/mo...ew-brakes.html

 

Is there any downside to mounting Naca ducts in the undertray like this? Any of you tried this? I've got the beatrush undertray and this would be a simple solution that would really cut hose length.

 

Interesting!

 

NACA ducts work off pressure differential vs actually "scooping" the airflo, so as long as there is a lower pressure on the backside of the duct they'll work fine. only way to really tell would be to apply some brake caliper temp stickers and do a blocked/unblocked track test to see how well they're work


for the person asking about small fans......consider using a radiator fan from a small ATV or motorcycle. they're down in the 4-6" range. Altough one good 7" fan and a proper ducting could cover both front brakes just fine.

quick google search popped this one up that's cheap

http://www.frozenboost.com/product_i...cab9c1bfa8c055

 

What about a Cool Shirt fan?

http://www.pegasusautoracing.com/pro...asp?RecID=5751

Or did you mean you were looking for high output 2" fans?

 

I was looking at those type of blower fans for some brake ducting I wanted to make.

 

Phil of Element Tuning has used them with great success on his time trial STI.

 

I like this idea tremendously.

 

[QUOTE=MSP608;9100133]What about a Cool Shirt fan?

http://www.pegasusautoracing.com/pro...asp?RecID=5751

Or did you mean you were looking for high output 2" fans?[/QUOTE

I guess the best is to stay with one 3" fan connected to two of the four 2" hoses. Each hub will receive one from the fan and one from a front duct. Just like a Trans Am race car but with half the air they use. Two 2" hoses are equal to about one 3".

 

Good thread...need to keep my eye on it, since I will probably be picking some of these up later in the year...

 

Bump - want to see if anyone else can provide input.