Mine is almost a direct clone of the CAI product concept. My lid is done differently but can be recut at anytime to enhance the seal. I had that portion of the car apart and back together about 3 dozen times within a 2 week period fabricating.
I used an AEM Dryflow filter from Fleabay and 2 layers of graphite header wrap sandwiched between 2 layers of 28ga sheetmetal and welded the layers together all the way around the edge. The lid is Lexan. Everything is 4" necked down to fit the 3" MAF and TB. I intended to convert to a 100mm MAF and TB upon completion of a cam/head/intake swap but got laid off from work after buying a ton of guns, ammo, and completing my 2011 Turbo Hayabusa so the car project got axed.
Test Fitting filter, tubing, and concept:
Bottom plate. This houses the ECM on rubber isolated standoffs as well.
Bottom Plate in vehicle during mockup:
Using cardboard as a template to precisely measure and cut all sides. This was fabbed pretty much completely in car using this method and my car as the mold.
The intake about 75% Complete. 3 walls are done and the baseplate finished. ECM and TCM are mounted in their permanent locations. In order to facilitate installation and removal plus allow the wires for the ECM inside i had to make this last wall removable and notch for the harness.
Top View
Intake complete before paint
Different View
One thing you will see in the last 2 pictures is the coolant overflow hose had to be rerouted. Actually the nipple on the overflow tank itself had to be cut flush, sealed off, and retapped into a different location because it interfered with the airbox. This airbox is fairly large and barely houses the AEM filter without issue in the configuration. There are several things i would've done different...mainly just buying the CAI kit if i ever did this a second time around but i just wanted to see if i could execute the project...and it came out pretty damn good. It seals almost completely up against the headlight bucket sans 2 or 3 spots that could be corrected with minimal foam. All in all a good result from a fairly difficult project.
and for those that will inevitably ask about the turbo hayabusa...here ya go. notice the pipes in the side panel? that panel is completely uncut. my fabricator did an AMAZING job. Unfortunately we ended up melting 2 pistons and bending 2 rods because of a wastegate issue (basically it couldn't open) and we saw 24psi 3 seperate times on pump gas. It didn't end well. Next on the list is a complete Wossner rotating assembly, 1/2" cylinder studs, main studs, cometic gasket, E85, and 425whp.