futurz

I'm new at this (owning a Porsche that is) and was wondering about the benefit, if any, to installing a K&N air filter? Took delivery of my new 991S in January. As mentioned, it is my first Porsche, which I purchased for my 60th birthday. It's way more car than I will ever learn to drive, but I have always wanted one, and now I have it.
No pictures yet, but it is Basalt Black with 2-tone black/platinum interior. Pretty much fully loaded. It has the glass sun roof which I like. I drive it with the cover open which provides a little more experience of openess. I opted against the CAB cause the sun is intense here in CO. I didn't buy winter wheels/tires partly because of expense and partly because when it snows here we get a lot of slush and just didn't want to deal with it. But I drive it any day it is warm and the streets are free of ice. Like today!
Appreciate reading all your posts on various subjects over the last few months although I admit I only found this site after I ordered the car, so it was too late to change anything anyways. Not that I would as I like it exactly the way it is.
Thanks

John 996 TT Cab

I bought a K&N for my 996 Turbo and took it to my independent Porsche Shop to install. They refused saying more problems than benefits. This has been discussed in the 996 TT forum quite a bit (not to do it). Check out that forum.

futurz

Thanks John. I will check it out.

neanicu

Why would you install that oily crap?!
I don't know if these new models are still using a MAF sensor,but if they do,the '' benefit '' of a K&N is changing the MAF more often.
Plus,does anyone believe their 10HP increase claim on different applications? It's an air filter for God's sake,how do you get more power from an air filter?!
And you do know the bumper needs to come off in order to get to the air filters,right?

futurz

I was just asking..... Thanks

neanicu

Didn't mean to scare you off...
I was just presenting my opinion,you can definitely do some research of your own,listen to others and decide for yourself...
Enjoy the car!

Quadcammer

don't bother.

Not to mention, according to 997 owners, the air filter can only be changed by ferdinand himself with the assistance of 14 engineers and the sacrifice of at least one goat.

pfijcali

I agree. It seems like too much trouble to get to the filters (2X), just to (maybe) get 2-3 more horsepower.

Navy CDR

I have a 2001 C4 that I modified for competition. One of the areas that I "improved" was to add a K&N filter.
DO NOT WASTE YOUR MONEY OR TIME.
It may provide you with a little more power but that can only be measured with sensors and accurate timing if you compete. Fouling the Mass Air Flow sensor is one thing that you will experience. You do not have to replace the sensor but clean it with a MAF cleaner but that is a pain in the butt. I have had my car dyno'd and I really cannot see the difference in HP at the wheels.
If I kept the original air filter box I would replace the K&N filter with it.

futurz

Based on these comments and the forum that John from Vancouver mentioned, I would say the question is closed for me. As I said in my post, the car is capable of more than I am. No mods for me. And it's a beautiful day here in Denver for enjoying the car!
Thanks

meine911

Update: Two goats for 991's.

John O'

I think the real issue for those of us living at altitude is the low end performance. I often wonder what my 991S would feel like at sea level. Products like the K&N air filter do seem to help with other vehicles. Does anyone have any suggestions?

Attilars

As I recall the 991 engine uses a MAP sensor instead of a MAF. Unfortunately I don't recall now where. Read this, but looking at some photos on the engine I don't see a MAF sensor between the throttle and air box.

Over the last several years I have seen threads like this pop up where someone complains about a failed MAF, but it seems to be an extremely small percentage of people having problems compared to the number of K&N, AFE, BMC, ... Filters used on various makes. Myself I've never had an issue on the several Porsche/BMWs I used these types of filters on. I'm curious how many of the problems reported are actually caused by people over oiling their filters.

Disregarding that, whether or not it is worth it is another debate. Assuming there is some small Hp improvement, on a car as powerful as a 991, being able to detect an increase of a couple hp is pretty difficult. I've seen the most noticeable improvements on less sporty cars with more restrictive stock intake systems.

Rainier_991

This is patently incorrect. Greeks sacrifice goats. Everybody knows that.
Germans from Stuttgart sacrifice beer.
If you need any proof of this, next time you take your Porsche to the shop, hand over a barrel of beer to the mechanic and see what happens (assuming he is from Stuttgart or at least has been properly trained in Stuttgart in the art of sacrifice).

Rainier

(Hick...)

simsgw

Congratulations on your first Porsche. I didn't get my first until 2009 and they don't disappoint, do they? And the 991 is even better than the 997, which seemed very unlikely if I'm honest.

I think you've already decided about the K&N, but in the spirit of flogging a dead horse, let me add my two cents. In our youth, and I'm about ten years older than you, we did a lot of that. And it wasn't tough at all to improve on factory performance. Most cars were barely designed at all in the intense way we mean that in this modern world of computers. Some of the great models adored in retrospect were knocked out in a few weekends of spare time, and the sporting models almost always were derivative of mundane cars. A sporting body on a ladder frame that hosted truck bodies in other applications. Maybe not quite that bad, but that's the spirit of the times. That and backyard/farmyard invention that won the second world war for a basically agrarian nation, combined to suggest that any half-decent tinkerer could gain ten percent more horsepower and the occasional genius with machine tools and spare time could double the output of a Detroit engine. And it was true. Mostly.

Outdoing factory design became so much an article of faith that many people believed the stories of a special secret carburetor that let your car run on water except the oil companies were buying up the patents and burning them in secret incinerators every night. Or something like that. Details have faded over the ages...

But that was then. This is now. Not only do factories have very subtle design tools, but they have strong financial impetus to make engines as efficient as possible. We are not correcting factory oversights these days when we modify our Porsches. They already are optimized when you consider car design at the level of Porsche engineering. The aftermarket isn't going to find a hundred horsepower the factory absentmindedly left lying on the floor.

What can be done is change the trade-offs. Design engineers always must trade-off this for that and tit for tat. The aftermarket just changes the more easily modified choices by offering less of that and perhaps a little more tit.

We have a design technique that takes a six-week seminar to justify mathematically but it's easy to picture. You know geodesic domes? Or that odd structure on the Thames that looks like someone draped a tent over a stack of pick-up sticks? Picture one of those. Now a sloppy inefficient design of anything is mired down in the middle somewhere. You won't see it. But those spiky bits, where the poles stick out in that odd Thames creation or where the corners come in a geodesic dome... those pointy parts are the good designs. A set of resources can be used to reach one point or another. This high point or that one. We have to choose. Some designers will choose this corner of the dome, some will choose that corner. But if you're at all efficient, or 'elegant' as we sometimes prefer to say, then your design is definitely at one of those points, not muddling along somewhere in between or God forbid lying forgotten on the floor deep inside.

Really good aftermarket engineers, and we have a lot of them, can take a design the factory put at one point, one pole sticking out, and move it over one spot this way or maybe two spots the other way.

You can get more power from the same factory engine by changing their decisions on those trade-offs. If you want more of this and less of that, say more torque but less chance of passing the California smog test, then someone will sell you a parts kit. Someone who really knows his business will take away things you don't care about, give you more horsepower in exchange, and still pass the smog test.

I know nothing of K&N Filters so I can't speak to those, but I do have a deep suspicion of carburetors that run on water. And supposing the factory left five horsepower lying around by choosing the wrong air filter for an engine that costs $30k or so... well that seems like a pretty damp notion.

Gary