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-   -   Brake ducts for OEM brakes (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/brake-ducts-oem-brakes-958757/)

MIBagentQ 06-18-11 08:02 PM

Brake ducts for OEM brakes
 
Cost of materials:

2x7.5" 16ga square pieces of aluminum $10 (one I kept as a template for more ducts)
12" of 1/8" thick 2.5" diameter aluminum tube (I only used 2" per duct) $5
3m of multi-purpose flexible duct hose $7

Total $22

Future plans:

1) re-do the backing plates with 1/8th" aluminum sheets
2) replace the cheap hose with something high temperature, either dryer duct or actual brake duct hose
3) build a proper front air intake duct

It generally started with some raw materials. I had the asked a local fab shop to take my 7.5" square sheets and cut them to exactly 7.25" diameter circles, the fitment inside the rotor is beautiful

http://farm6.static.flickr.com/5301/...ff2cfe0f_b.jpg

Then it's a whole bunch of trial and error to get the two bolt holes and ABS sensor hole lined up. I cut off the third bolt ear off the hub to give more room for the duct

http://farm4.static.flickr.com/3268/...592833be_b.jpg

test fitting, the gap between the backing plate and the rotor is pretty big, but I got this to be much smaller later by adding a few washers to the backing plate. The rotor is also not fully bolted on to the hub yet

http://farm3.static.flickr.com/2711/...25fdeb56_b.jpg

The 2.5" OD pipe was brazed onto the backing plate using some benzomatic MAPP gas torch and some aluminum brazing rods, I think they're called dura-fix rods, I picked them up off ebay for cheap

http://farm4.static.flickr.com/3534/...93a1874a_b.jpg

used an old intercooler hose clamp to clamp the multi-purpose flexible hose to the 2.5" pipe

http://farm4.static.flickr.com/3372/...d6c5d8d6_b.jpg

zip tying the hose out of the way so that it doesn't hit the tire (I hope, haven't taken it out yet)

http://farm3.static.flickr.com/2423/...e6c7c352_b.jpg

driver side

http://farm4.static.flickr.com/3217/...aea7e9a5_b.jpg

final clearance is much much closer to the rotor

http://farm4.static.flickr.com/3060/...2828bbe9_b.jpg

http://farm3.static.flickr.com/2550/...6a044b6f_b.jpg

last step, to do something about this :S

http://farm4.static.flickr.com/3524/...58ee0538_b.jpg

Will be running Hawk DTC 60 pads in the front, DTC 30's in the rear with blank rotors. Will report after next weekend to see how the new pads and new ducting setup works!

Last track day I ran HPS fronts with OEM rears and no ducting. Killed the brakes after the first session :(

jspecusa 06-18-11 09:00 PM

good idea.
I would also suggest the following.
1. cut a hole in the front bumper and put a velocity stack on it for more
ram air cooling.
2. weld some aluminum fins in the back of that dusk cover disc for more
cooling.
You can cover up the front hole when it's rains.

GodSquadMandrake 06-18-11 09:51 PM

That's quite interesting. Let us know how it works.

Miata_mx5 06-19-11 12:15 AM

https://www.rx7club.com/showthread.p...=JhnRx7&page=3

MIBagentQ 06-11-12 03:47 PM

one year update on this thread:

upgraded the hose to some proper silicone hose, this stuff's expensive so I just used a few feet of it where where it connects to the brake ducts, and the rest of it I used home depot flexible duct and a crapload of zip ties to hold everything in place

https://farm7.staticflickr.com/6131/...211c7d58_b.jpg

routing the hose to the front R1 lip, lots of use of aluminum ducting tape for sealing

https://farm7.staticflickr.com/6140/...6382d32f_b.jpg

driver side

https://farm7.staticflickr.com/6134/...d381ca93_b.jpg

sealed up front

https://farm7.staticflickr.com/6001/...39661dc6_b.jpg


Review:
Pads are hawk DTC-60 front and hawk DTC-15 rear. Rotors are plain old brembo blank rotors. With these brake ducts, running 245 r-compound tires all around, I had absolutely no issues with brake fade, either pad fade nor fluid fade.

With the success I've had with these pads and rotors, I don't see any reason personally to go BBK. Replacement pads and rotors are cheaper (er, not cheap), and they just work.

Brake feel is very grabby before the pads warm up, but once they're warm, the pad feel is amazing, smooth, progressive, but if you want, you can lock up fresh 245 Hoosier R6's without too excessive effort.

MIBagentQ 06-11-12 03:49 PM

Brake bedding is important, in order to bed my brakes, I stuffed rags in my brake duct openings in order to allow the rotors to get nice and hot. Screenshots from the video from my Go Pro


Before the pads/rotors are at operating temperature:
https://farm9.staticflickr.com/8147/...0c2e78dc_b.jpg

After the pads/rotors are at operating temperature:
https://farm9.staticflickr.com/8012/...04a5416d_b.jpg

thewird 06-11-12 04:09 PM

Hehe, I remember the first time I bedded in my DTC-70's at night and scared the shit out of me when sparks were flying everywhere LOL.

thewird

Brekyrself 06-11-12 04:55 PM

Thanks for the update on the ducts.

Just curious, have you tried running DTC-60's in the rear also vs the split setup?

Fortune_Seven 06-11-12 11:52 PM

Cool setup!

thewird 06-12-12 12:07 AM


Originally Posted by Brekyrself (Post 11120751)
Thanks for the update on the ducts.

Just curious, have you tried running DTC-60's in the rear also vs the split setup?

FD's don't need rear brakes so you'd be eating your rotors for no benefit. I tried a lot of brake pad combo's before deciding on this one was the best. HP plus works just as well on the rear but doesn't last as long as the DTC's.

thewird

MIBagentQ 06-12-12 09:37 AM


Originally Posted by Brekyrself (Post 11120751)
Thanks for the update on the ducts.

Just curious, have you tried running DTC-60's in the rear also vs the split setup?

I have not tried this, so far the 60/30 setup has been working fine for me, braking certainly isn't my weakest link so I'll address my other weak links before revisiting braking (driver experience, tires, aero's, weight reduction)


Operating temps for the 60's are 400-1600F and the 30's are 100-1200, not sure with my style of driving if I'd get the rears up to temp or not :S

MIBagentQ 06-12-12 09:40 AM

oops I just realized I said I am using DTC-60/DTC-15 on my original post, this is incorrect, I am actually using DTC-60/DTC-30

evot23 06-12-12 09:59 AM

wow...that's a lot of ducting...nice


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