Took some time Sunday to start the brake duct project. Very similar to what 1977and2010 and many other have done. I am using a 2-1/2 hose instead though. While a 2 inch hose would definitely be easier to route, I want the larger diameter because eventually I'll make some parts from fiberglass to replace what is routed along the frame. I'll only need a short section of duct tubing from the frame to the dust shield, and from the front NACA ducts to the fiberglass ducting. Right now I need something for a big track outing in May and need this working.
So here what I used from Racer Parts Wholesale. I like their ducts because of the plastic they use can be formed by heating it up. You'll see what I mean in a few pictures what I did with the bumper duct.
2 - SPA-D103A 3" to 2-1/2" NACA Duct Adapter
2 - SPA-D107 Small, Black Air Duct for Bumper, Spoiler or Small Area
1 - THE-SS250 2-1/2" Silicone Ducting- 11' Section
2 - The short steel pipe used to connect to silicone ducting to the dust shield is just a 2-1/2" muffler connector bought at Autozone.
This is the bumper duct cut and bent to fit in the lower air dam.
Using a heat gun, a couple of pieces of aluminum and vise grips I carefully bent the duct. This was done to fit the angle in the lower air dam to give it a finish look.
Here's the backside of the air dam marked off for where I will make the cutout to fit the bumper duct.
Backside of air dam after cutting. Used a dremel with a cutting bit which made it quick and easy.
This is the bumper duct mounted to the air dam.
This is what it looks like from the front. You can see on the right side where the bumper duct that was bent fits over the angled part of the air dam. This helps support it as well.
Here's how the duct attaches to the dust shield. I'll mark the shield up, cut the hole and weld the round tube to it. I'll be taking the shields off because I need to replace the dust shields on my calipers anyway. I can then trim off some extra metal and paint them up nice.
So I'll need to run the duct below the control arm instead of going over it. The 2-1/2 hose will get crushed with the suspension compressed; a 2 in hose might make it through there but my feeling it is will rub also.
I took a bunch more pictures, but this should give you guys some more food for thought. Most of these implementations have been similar, so nothing earth shattering with mine. The only thing I will do differently in the future is to design a duct system made of fiber glass to run along the
frame and avoid the issues with the control arms. For now this will have to wait, time to get on the track.