replaces convoluted plastic intake route consisting of.
1. narrow cold inlet
2. convoluted snorkel tube thingy
3. restrictive intake pipe
4. convoluted plenum chamber.
All of the above seems to be in place to restrict noise output but seems such a convoluted way to get air into the engine that it must rob power.
After market intakes are available for upwards of $150 bit I thought I could make my own far more inexpensively. I purchased a large conical filter from *********. It comes with a fabricated adapter plate that allows the filter to be bolted to the air flow mater and is intended as a replacement for the standard air box and snorkel. This would seem to be a vast improvement in itself but still leaves in place the narrow corrugated intake pipe and large plastic plenum chamber. Other intakes replace all this with an aluminum tube but I replaced mine with 3" PVC pipe from the local hardware store for $**.**.
10" of 3" schedule 40 PVC pipe
1 x 90 degree male/female elbow
1 x 45 degree male/female elbow
1 x 3" to 2" rubber adapter piece
1 x 3" rubber collar
2 x 1/2" male/female elbows
PVC cement
1" jubilee clamp
1 x 1/2" tee
6" of 1/2" flexible pipe.
Installation is very straight forward. Firstly I removed all the plastic OEM intake including the snorkel from the fender well. This opens up two large holes that may allow cooler air into the engine compartment right where the new air filter sits. I assemble all the 3" components and dry fit them before gluing them up. This allowed me to position the various bits of pipe that feed into the intake at various places. I teed together the ones under the plenum chamber and fed them to an elbow I placed in the 90 degree bend. I used a 5/8" drill and PVC cement to attach two 1/2" elbows for these pipes. One under the straight piece and one under the 90 degree bend. Then I glued everything in place and waited for it to set before installing it. I did cobble together a support off the original plenum support but I don't know it is really necessary.
One more necessary modification was to relocate the alarm siren from the suspension tower to the space vacated by the intake plenum. I mounted it the the plenum mounting bracket. This was to allow more room for the new cone filter.
There has been a significant increase in noise as a result of this modification. This is a pleasant "grunt" past part throttle but I don't think it is too loud. It has a bit of plastic bucket to it. Most of this noise (90%) arrived after replacing the plenum chamber adjacent to the throttle body. Previously I had just changed the filter box and pipe which seemed to release some power and just a little extra sound.
Throttle response seems enhanced and the car seems to pull stronger too. It actually seems to handle better as well, but I think this is a consequence of how much more I am enjoying driving the car with this new intake..