DSPTurtle

Not being one to leave well enough alone, I decided this weekend to remove the snorkels/silencers from my 2004 Cayenne S. Why? Well a few weeks back I purchased the Durametric cable and software. Once I started playing with the data logging feature I noticed I could record sensor data from each MAF independently. So I unhooked one of the airboxes and noticed that all the air was now flowing in from that side. Not believing the hype of the Evo cold air intake I pulled the entire airbox and connected it upside down to the MAF with no connection to the snorkel/silencer. Well, that side was still favored by the motor. I started digging further into where the snorkel was sucking air from. I could quickly tell that not one of the huge intakes on the front spoiler was feeding air to the engine, only the radiators. I found that the snorkel intake was tucked under the Porsche badge on the front. How it could get air from in there is still a mystery to me. I went about the task of removing the snorkels from each side. This is certainly not a job for the faint of heart. On the first side I had to remove the inner wheel liner just so I could figure out how everything was routed. The second went a little easier. However, I must tell you that the snorkel must be removed from the top... by pulling back on the area where the badge resides. It reminded me of when my wife gave birth to our children. Once all was removed and replaced I could feel a difference in the throttle and hear a difference when the motor inhaled. I left the stock airboxes in the original configuration with simply the snorkels removed.
A long time ago I hooked up a lot of data acquisition equipment to a homemade cold air intake for a 540i6 that I used to have. Basically, I was able to empirically prove that these things only work when the car is moving. I reproved that theory by monitoring the intake air temp with the durametric software on the Cayenne.
In the future I will look for a way to duct some air towards the opening in the stock airbox. As it sits right now, the stock air box is drawing air from the exact same spot as the Evo CAI as far as I can tell.
If anyone is interested I will gladly post some pics but I dont want to bore anyone needlessly.
Cost... $0, a little bit of blood and a new set of torx screwdrivers.
Be able to hear the Cayenne take a big breath... priceless
I look forward to hearing if anyone else has done this mod!!!

User 4221

Thanks for the insight. Empirical data beats marketing hype any day.

Correct me if I'm wrong, but I think the summary of your efforts is:

1. Measured stock air intake and temp.
2. Removed one side, opened it up and saw more airflow from open side.
3. Noticed that airflow is restricted by path and snorkel.
4. Deduced that Evo kit would provide little improvement over stock kit due to system design
5. Measured that removing snorkel/restrictor improves airflow.... Thus improves power!

Is this right? If so, this is good info.

Thanks for the post.

Full Boost

Ok - I'm interested - would love some pics?

Simon.

DSPTurtle

Scott pretty much summed it up with those five steps. Only thing is to not put too much of a negative slant on the Evo kit. To get essentially the same effect without scratching the hell out of yourself and a lot of cursing, the Evo kit would do the same thing. It is just that I did not want to spend my mod budget on something I could easily do myself. If anyone has the Evo kit it would be awesome if you could give us the measurements of the cone filter so that we could calculate the surface area. I am willing to bet that the Evo kit has a much smaller surface area then what is aready in the truck... those stock filters are huge!!! If you notice on the Siberian version, Porsche went with a much bigger MAF and piping to the throttle body. Unfortunately I have no idea how to recalibrate the DME for a bigger MAF so I am just trying to make the best with the stuff already on the car. Pics to follow...

DSPTurtle

First picture is where the snorkel hits the airbox... taken after removing the wheel liner so you are looking from over the brake caliper on drivers side.

DSPTurtle

Second picture is how the snorkel is routed to the front of the vehicle... again from over the brake caliper with wheel liner removed.

DSPTurtle

Third picture is with me pulling up (hard) on the top of the plastic spoiler where the Porsche badge sits (you have to remove all of the fasteners at the front of the engine compartment). This shows where the outside air gets into the snorkel. Apparently there are a few slots cut right above the radiator.

DSPTurtle

This is what the airbox looks like after being reinstalled with no snorkel. Notice the cold A/C lines running right near the airbox opening. Not sure if this will have any effect on the surrounding air temp but at least those are the cold lines and not hot.

DSPTurtle

And finally... what the removed pieces look like. I guess I could have just cut them but wanted to save them just in case I ever have to go back to stock for some reason. Front bumper woudl definitely have to come off, or at least be significantly loosened up if I were ever to reinstall.

DSPTurtle

Overall I am glad that I can now here the Pepper inhale. On top of that I was able to not mess around with any cutting or electronics so it looks box stock unless you removed the wheel liner. I will probably figure out how to duct some air into that area for the next go round... if I can find some stock airboxes on ebay I might experiment with cutting bigger intake holes up higher on the box to be able to get the same height on the intake draw (about 4-6") in case I decide to drive through any rivers

uder26

Wow, way above my level of expertise, but what a great post!

ozr

...thanks to Kevin M, he has a good gallery pic, representing air distribution at the car front:

http://gallery.rennlist.com/cayenneg...4-S/agr?full=1

...and page 55 in PET doc:

http://www.lilyandgrace.com/pet/docs...SA_KATALOG.PDF

...air intake mod on a transsyberia Cayennes, many pics at:
http://www.transsyberia-rallye.de/en...t/pressphotos/











Enjoy,


OZRacing

AndreCT

Ok. great post .. and sorry to go off topic but OZ, how did you get to post those pics like that. I have to think they are bigger than the 1024 x 1024 limit I keep being reminded of when I try post. I need to go and downsize the resolution on my camera, then go take pics, then crop to fit and then post.

Those you have posted are amazing in their detail and size.. so please let me know what I am doing wrong.. tks in advance.

And sorry again for hi-jacking the original post.

yetis

When you get the size limit, you are trying to download a picture. That is, you are clicking the button that says "Manage Attachments". OZ's photos above are links. To do this, you need to either lift the photos from another site (like the ones above), of host the pictures on another server such as Photobucket.com. With the URL, you click the button that says "insert image" and add in the URL.

The pics above are from http://www.transsyberia-rallye.de/uploads/pics

AndreCT

hah.. I learn something new everyday.. many thanks Chris..