DIY - CHEAP Brake Duct System

[aus]

That ducting is HUGE!!!

I'm really interested to see how your brakes hold up after the StopTech's with ducting.
Thanks again.

[ScheerSpeed]

i found aluminum duct inlets

i just ordered 4 of these

http://www.aircraftspruce.com/catalo...uctflanges.php

[Jaypod]

Originally Posted by ScheerSpeed

i found aluminum duct inlets

i just ordered 4 of these

http://www.aircraftspruce.com/catalo...uctflanges.php

Make sure you post pics once you install.

[kero]

interesting!

[adc]

I just bought a set of 3" alu flanges and I'm planning on doing the brake duct mod.

I plan to cut & fit them to the underbody panel, then anodize them black and use OEM fasteners to secure them into the panel. I'm thinking of providing the brake ducting just into the wheel well plastic shroud, without going all the way to a backing plate. My reasoning is that my previous BMW's all had this type of arrangement and I was fine at the track when using track pads.

I'll keep everyone posted with my progress...

[GewoW]

Originally Posted by adc

I just bought a set of 3" alu flanges and I'm planning on doing the brake duct mod.

I plan to cut & fit them to the underbody panel, then anodize them black and use OEM fasteners to secure them into the panel. I'm thinking of providing the brake ducting just into the wheel well plastic shroud, without going all the way to a backing plate. My reasoning is that my previous BMW's all had this type of arrangement and I was fine at the track when using track pads.

I'll keep everyone posted with my progress...

any update?

[adc]

Originally Posted by GewoW

any update?

My apologies, I haven't forgotten about it, just got delayed a bit... After careful measurement with my precision eyeballing system I've determined the 3" flange is a little too big.

So I've ordered a set of 2" flanges which unfortunately got lost in the mail - I have another set on order and will proceed as soon as they arrive.

I'm also trying to find a local shop who can anodize the flanges after I cut/drill them - it'd be nice if they were all black (and I don't think paint would last).

[GewoW]

Originally Posted by adc

My apologies, I haven't forgotten about it, just got delayed a bit... After careful measurement with my precision eyeballing system I've determined the 3" flange is a little too big.

So I've ordered a set of 2" flanges which unfortunately got lost in the mail - I have another set on order and will proceed as soon as they arrive.

I'm also trying to find a local shop who can anodize the flanges after I cut/drill them - it'd be nice if they were all black (and I don't think paint would last).

Thanks for the follow-up! Let us know how it goes

[isugoo]

I.. see... dead... people....



Awesome job, BTW!

[MaxL]

subscribed. keep us posted on the build.

[donovan]

update

[lve2xlr8]

It's bizarre that the 335 has brake cooling but not the m3...

[008]

My vote for best thread on the forum. Great work OP. RRT used to make an economical kit for the E46 M3 but have nothing for the E92. My hose should arrive today and I'll play around with it this weekend to come up with a routing that will work for track days but not permanent. I don't have your patience anymore.

[///My5UV]

Anyone that's done this having issues with brake ducts getting pinched or damaged with full steering lock? My E36 has bimmerworld brake ducts in two sections... one from the front bumper to a flange in the fender liner, and another section that I usually leave disconnected that goes from the fender liner to the backing plate. If I use full steering lock the duct gets pinched or torn so that section is only for the track.

I like those turner inlets, but that's a bit pricey compared to hacking in something generic. Ditto on bimmerworld's $250 (per side) CF backing plates, but at least those aren't just plastic.

BTW, the inlets seen on those racecars are called NACA ducts. It's a shape that was found in aircraft research in the quest to bring air into a flat surface with minimum drag. Pegasus sells generic plastic ones in different sizes for around $20. For that matter they have generic rectangular air inlets for $23.

If you're worried about critters getting in, then it shouldn't be too hard to work in some wire mesh (aka chicken wire :-)

[rocket_science]

Or you could just go with these...
http://www.bmw-planet.com/diagrams/r.../e90/index.htm


$199.00

[adc]

Originally Posted by rocket_science

Or you could just go with these...
http://www.bmw-planet.com/diagrams/r.../e90/index.htm


$199.00

The only potential problem with these is that I think they take 3" hoses. I found it much easier to route 2.5" inside the under tray, there isn't a lot of space there...

But it might be worth it even so, and it may be easy to fabricate a step down adapter if you still want to go with the smaller hoses.

[Porschefile]

They also kind of defeat the purpose of the cheap brake cooling plan. My flanges from aircraft spruce were like $10 and do the same job. The Apex ducts may flow slightly better, but definitely not worth 20x. I did this DIY with success. The hard part is getting the hose to not rub when turning (especially parking).

[adc]

Originally Posted by Porschefile

They also kind of defeat the purpose of the cheap brake cooling plan. My flanges from aircraft spruce were like $10 and do the same job. The Apex ducts may flow slightly better, but definitely not worth 20x. I did this DIY with success. The hard part is getting the hose to not rub when turning (especially parking).

Do you have any pics?

[Porschefile]

Originally Posted by adc

Do you have any pics?

Here are a few. I don't have any of the undertray in detail, but I did it just like Junior did. I have ran the ducts for about 3 months off and on. I take the hoses off when I'm not going to the track and just leave the hole there. It rubs past 1 turn either way. Not an issue on track, but is annoying in city driving. I used them at Barber and VIR and had no issues with pinching or tearing etc. I don't have data on how much they helped cooling, but can't hurt. Probably won't run them with my ST60's now because I doubt I can fade those even without ducts. Everyone that has seen the car thinks they're aftermarket from some tuner or OEM (now that I painted the rivets black anyway ).

Used:

2.5" hose 3.5" inlet flanges here for under $8 each http://www.aircraftspruce.com/catalo...uctflanges.php

2.5" SCEET hosing from aircraft spruce (bought 8 feet but only needed like 6)

2.5" 2 sided flanges from aircraft spruce

Rivet gun

Total cost was around $120 + 4-5 hours

[kaiv]

Very cool, Trey! I think I might have to do just that

[adc]

Nice! So how exactly do you remove them? All the way to the front of the car?

[Porschefile]

Originally Posted by kaiv

Very cool, Trey! I think I might have to do just that

Yep, you do. It's a must for stock brakes. My rotors were still glowing with PFC 01's and heavy braking.

ADC, I remove the whole hose when not going to the track. It only takes me 30 minutes to an hour to raise the front, pull the underpanel, and undo the hose. I leave the flanges in place.