FOr all you lovers of your SOT roots kits out there you know that one of the drawbacks is the "challenging" position of the air intake. As Camuman pointed out to me and I did not pay that much attention to during my install process the thottle body has a 3" diameter, but the setup of the intake hose is reduced to something like 2.75 or less. The gap represents the extra airflow you could be getting.

Seen here:





And makes you use a fairly small filter versus the larger K&N I am using now, the RU 2820. It is about an inch and a half longer, 1 inch larger outer diameter, and has a flange diameter that is a quarter inch larger than the one included with the kit.

 

What I have done was fairly easy. I moved two things, the power steering computer module and the fuse box. I did not do a complete relocate that would require cutting and soldering just moved them to the extent the wiring harnesses would allow. The fuse box I moved the bracket over as far as it would go over to the wheel hump and tilted it so that the fusebox would be as far to the front of the car as possible and down against the wheel hump as far as it would go. In order to do this, I used a nibbler to cut away some of the plastic on the bottom of the fuse box where the main wires go in so that it would slide an extra inch. If you flip it over you will see what I mean.

The I detached the power steering computer and mounted it flat where the battery tray used to be. I used one of the existing holes, drilled a second, and used a dab of silicone on the bottom just in case it would rattle. It is easiest to disconnect the wiring harnesses and secure it down and then attach the wires again. But keep in mind the harness clips on either side are the same but if you reverse them as I did (because once you put it down flat you need to reverse the positions of the harness clips, what was on the right before now goes in on the left, vice versa) you will have no power steering and a warning light. Putting them back the way they should and it works just fine.

It now looks like this:

 

Basically the rest was pretty easy, trim the silicone elbow that attaches to the throttle body as much as you can to still get a hose clamp on it and be flush against the throttle body.

Then I purchased

K&N RU 2820 air filter $40 at amazon

Two pieces of aluminum pipe from Speedy Metals at two inches in length each at their thinnest wall to maximize inner diameter. That was about $25 shipped.

Finally a 45% 3 inch silicone elbow for about $14 from someplace like Silicone Intakes.com or something and a couple hose clamps from Menards.

The finished product is nothing genius or anything but looking down into the engine bay you can now see lots more open space around the filter, and the filter has MUCH more surface area. It feels like it breaths a little easier than it had before but I don't have anything to back that up with, just my impression and the finished product after you trim the new 45% elbow to fit everything up right looks like this.....





You can now easily see the angle at which the fuse box is tilted to match the wheel arch. When you are done you can actually see much more daylight around the filter where it looked a little more crowded before.

It also becomes obvious when you do this that if you took the time and effort to do the common relocation of the fuse box and power steering computer into the inside of the fender cubbies like many turbo guys do you would have LOTS of room for the filter and be able to fairly easily channel cool air from under the car directly to the filter. But that is for when I have more time and energy.

Thats it, if anybody cared.

 

It basically the first pic versus the second pic.

 

I just saw neptuner's scratchbuilt airbox for the SOT/BRP kit today. I think he managed to get a bigger air filter by moving the fuse box to the front crossmember.

to a bigger filter. It's one of the details on the SOT kit that I'm not crazy about.

 

dang, yours looks way bettter then mine. mental note, i will never post a pic of my intake setup now.

 

any chance you could get to a dyno and see if it produces any gains?

 

Maybe. I will take it back to the dyno in about 6 weeks and if I have it for an hour it would take five minutes to do a pull with the old filter.

 

Wow, didn't realize the filter was all the way back there on an SOT kit. It may just be me, but seems as though this location would be the bigger factor vs being in more of the stock location with some cooler fresh flowing air.

Cut out that hood and get a snorkel/hood scoop on that bitch

 

I agree that the SOT kit leaves room for improvement on the air filter and piping. The mods made by Vader1 look good and should improve air flow.

On my S, I also got rid of the smaller intake tube and went to a larger K&N X-Stream filter. To get some cooler air to the filter, I cut a hole in the hood and mounted a NACA duct above the air filter. Like Slows2k said, I recently made an air box to contain the air from the NACA duct around the air filter. This arrangement is almost identical to the one used by WLaurent which he reported to show siginificant reduction in IATs.

To make room for the air box, I relocated the fuse box forward (without cutting the harness) into the space vacated by the OEM air box. The power steering module was moved to inside the fender (without cutting the wires).