Cold Air Induction
Part of the upgrade to the intake system is the addition of cold air induction and the replacement of the stock airbox.
I have designed a new airbox that will go inplace of the battery (which will be relocated to the boot) and contain my new Apex'i Power Intake pod filter.
From there to the throttlebody will be a 3" mandrel bent pipe in either stainless or alloy with a silicone reducer to join the 3" pipe to the 2.5" throttlebody. From the airbox, there will be a 3" duct to the front bar, the same stuff I used for the brake ducts, just larger.
Here is the new Apex'i filter and the new airbox design. The design is provided as a .PDF so you can print it out and build your own. It is printed over 6 pages and stuck together page edge to page edge. Cut the outline from aluminium sheet and bend up as one piece. The hole is slightly larger than 3", but can be sized to your individual requirements.
The 3 tabs on the drawing are used to attach the box to existing bolts. You just have to bend them as needed and drill the correct size holes. A washer between the bolt and aluminium would probably be a good idea too.
I went to the local pipe fabrication place I normally use, Radius Benders, and got them to bend me a piece of 3" 1600mm or so long aluminium pipe in the middle by 45 degrees. Once that was done and I had got my hose clamps and silicone bends from Ebay, I set to work...
When you cut out the airbox, use a jigsaw blase with REALLY fine teeth. That way it won't 'bite' the aluminium and bend it. Also, where the hole is for the pipe to pass through, leave two tabs. This is to clamp under the hose clamp and support the filter.
Here you can see the tabs. Just massage them into place with a pair of pliers.
Once you've cut the pipe to size and bolted it all together, it should look something like this. (Ignore the dodgy tape, it's temporary until the catch can is installed...) You'll probably notice that there are a few pipes left over. All I did was get some brass fittings from Autobarn and tapped them into the pipe. One is for Idle control, one is for crank case ventillation (your catch can goes between here and the rocker cover) and one is for... something else..... ? :) To seal the airbox to the bonnet, I just used a bit of rubber boot seal. If you go to the wreckers, you chould be able to get some cheap. To make sure it seals correctly, take out the headlight and close the bonnet. Make sure there is an even gap between the bonnet and the airbox that the rubber can seal. I used a black texta to trace the contours of the bonnet onto the aluminium then cut along the line.