bmwm750

And they flow plenty more dirt too

mishar

... and increase filtering power, but most certainly not the fuel consumption. It is just as you pressed your gas pedal a bit less. The only way to lower intake resistance and keep same level of filtering is to use bigger filter. Or two of them like S8's and W12's.

chiefironbear

Thanks for the post guys. I just purchased my 07 S8 with 56,000 miles so this is a definite project this weekend. Pictures are priceless. Great help as always on this forum.

tdawg183

I'll go ahead and apologize for calling you out as you are a much more senior member of the forum but I had to chime in that this is a very incorrect statement. There are many different design characteristics of material flow (through filters in this case), apart from size, that can provide the means to lower intake resistance and keep the same level of filtering.

I am straining to not go full-blown textile engineer on this topic. ha.

haggisuk

Thanks for the write up, must get round to checking mine,

On the topic of filters to use the following might be of interest to read when you have 5

http://www.nicoclub.com/archives/kn-vs-oem-filter.html

mishar

No apologies needed at all. Discussing those things is a very good and simple way to learn something new.

So, you are saying that there are better filtering materials than those used in standard automotive filters. Let's see how feasible, economical and useful would be building a custom filter using one of those supreme materials.

By the way, if anybody wants to feel all possible gain from lowering intake resistance just take your filter out and try how much better your car goes (if you can feel or measure any difference).

jakematic

This was recently suggested in another forum here on AW, the idea being to measure 0-60 times.

tdawg183

Ha! and yes, good point, let's not talk the price of said materials.

Alexxelax

Hi, Do the servo oil need to be changed? I read that the fluid should be a green fluid called green something. But i didnt see anything about how many Liters, do anyone know? And i saw a tip on how to suck it out.

I asked i while ago about a whining sound, and i now suspect it is the steering power, and when turning the steering wheel it feels a little halting.


Have anyone had this problem? and possible solutions

MP4.2+6.0

There is no spec for changing the fluid. Assuming the S8 is pretty much like the W12--the reservoir is in the same really awkward place where you have to take out the driver's side airbox to get at it--I have concluded it is almost impossible to drain. On my prior C5 4.2, I could just suck fresh fluid from a can while pumping out old by connecting to the cooler lines for it, but I see no way to disconnect any hoses on my W12. What I do is every time I have that air box out, I get in there with a turkey baster and suck out as much old fluid in the reservoir as I can.

Yes, your symptoms do sound like the steering/pump. Perhaps just tired. About all I can suggest to do is check fluid level, and with motor running turn the wheel hard from hard left to hard right and back several times. That can help get air out of the system if there is any. Less strain on the system if done with the front wheels are off the ground.