Thanks for the feedback!! When you reset the computer the car will need to make new fuel maps to adjust for the new air flow. Some times in the first few minutes it feels like the computer is on the "safe" side while it learns, but as you put miles on the car it will feel stronger. There are fuel maps for many different variables from stop and go traffic to partial throttle in every gear all the way up to full throttle in each gear. So it takes a few drives to remap all those parameters.

Throttle response should feel a bit sharper all around as you seemed to mention, but your first impressions are some what correct in that below 5000 rpm hp gain is very modest, maybe a few hp. This modification makes its greatest improvement between 5000-6500 which I am sure you must have seen from the dyno charts if you did your homework like you said. This is where I noticed the biggest improvement when I first got it. I use to feel a flat spot in power from 5000-5500 and then a bigger boost in power as it seems to come on cam and increase power into the upper rpms. After adding the intake I could tell it pulled stronger through the old flat spot and then there is the sound and wail it makes 5000-7000 rpm... Proud poppa syndrome or not, this thing makes a nice scream up top. You mentioned you really notice the sound, but are you happy with the intake sound?? I could not tell from your comment if you were enjoying the new sound or not.

I live in Los Angeles with very dry weather and temps get really hot in the summer where I work. About 100 degrees during the summer months. I have had this Intake on for several years and never had any "heat" issues with performance dropping. I mean... All cars in winter time feel strong from the cold air outside as well as in hot summer days you will feel a bit down on power due to less dense air, but I never felt like I took any steps backwards in performance. Even in the summer months.

Well, I hope you enjoy it. I wonder if the different cone filter you used has any effect on the sound it makes. hmmmmm I would think not, but I am sure the acoustics have changed very slightly with a longer cone vs short cone design. It should still sound great in the upper rpms. Keep us posted!

One thing I would like to add... Use CRC Mass air flow spray cleaner every 6 months just to be sure maf is running at optimum. Another issue, which is not related to maf or intake, but you may think it is if it ever happens to you. Bad gas will make our cars buck like a bronco and feel like its choking for several miles. When this happened I thought my maf was bad or something was really wrong with my car, but the Porsche tech told me I got some bad gas in the system and should use Techron Fuel cleaner as soon as possible and fill up at Chevron for a few cycles. Amazing how bad fuel affects our cars. freaked me out! All was good after that.

 

Here are couple other videos to hear the kind of sound mine is making.




At the track recorded with GoPro camera mounted on rear window. (no special or additional mic)

at the track with my android samsung phone recording while attached to front windshield. side windows open, sorry, wind noise, but you can still hear the engine good.




this is recorded using a gopro camera suctioned to the rear window for the inside camera shots. windows down, but you can really hear the sound kick in at 5500 rpm. The camera is sitting right over the engine, so the intake wail may sound more pronounced in the back seat area.

 

Does the K&N mod only work for a 997.1? What about for a 997.2?

 

I know, I kind of feel like we are in the mid 90s with talks of gaining 25HP in a honda civic with just a CAI. I thought we have moved far beyond that, and here we are 20 years later on a $100k car claiming the same thing?

There has to be several hundred dyno sheets out there showing the gains and these would be selling all over the place.

Hey, don't get me wrong, I would love as much as anyone if these things produced that much HP for that price (I even know someone at KN that can get me this product at an even better price), but frankly, I just don't buy it. I have had 3 cars over the past 10ish years in the 300HP range, in the 350Z it was pretty well proven that the filter (even a NISMO version, owned by Nissan) was "claimed" to only produce 5.5hp (dynos showed 0-6HP gain). My E46 M3 it was pretty well understood that the CAI pretty much did nothing as well. An now all of the sudden PORSCHE went stupid and left 20-30 HP on the table with a CAI? Huh?

When I had my Z, I went with all the NISMO stuff (headers, exhaust, and CAI) simply because I knew what I was getting. PERIOD. I may have had items with less HP claims, but for me, I knew they were legit, because Nissan can't make the crazy claims and not back them up (see what happened with Mazda and Ford when they make false claims). Sure wish we had a bunch of dynos

 

-K&N Intake Kit # 57-7000... My main concern is that each computers fuel maps take in to calculations the diameter size of the maf housing to measure air flow. I would measure the diameter of your stock MAF housing. This kit uses a 3 inch intake tube that the Maf sensor plugs in to. If your stock maf housing diameter is bigger than 3 inches then your air flow readings will be a bit off and cause a lean fuel ratio situation.

I believe the 997.2 uses the 82mm (3 1/4 inches) GT3 throttle body which may mean that the maf housing is 82mm, but I am not sure. I would be curious to hear what the measurement is. If it is 3 inches in diameter then this very well could work.

 

I hear ya and I am very skeptical myself about certain companies and their bolt on mod hp claims. It's also one of the reasons I have not done too many mods on the engine. In the past I totally have been disappointed over the years with many bolt on modifications on other cars I have owned. I know all too well about bogus horsepower claims. I also know that some mods done in the right combination can add nice increases. I spent over a decade modifying mitsubishi cars in the 1990's making up to 500 hp on 25 psi of boost. So I have seen it all and heard it all.

My first response is I never claimed this single mod gained 25hp. K&N dynos show a nice 20 hp increase in the mid range and a small 7-10 hp increase at the top end. I use the K&N in combo with an ipd plenum and I noticed a really nice difference in throttle response, power and above all the sound is awesome to me. Next, please take no offense, I worked over a decade with japanese engines and you can't compare a 3.8 liter 355 hp Porsche engine to a 1.8 liter honda civic or even a 3.5 liter nissan Z. Sorry, just Totally different animals and Porsches intake manifolds respond differently to air flow with the way they are designed.

I also spent dozens of hours on the dynos over the years doing a Porsche engine conversion and dyno tuning different mods so I have learned what to expect from certain parts on porsche engines too. All I can say is sometimes you find a winner and a part that makes you happy with a small increase in performance and sound. To me, this intake is worth it just to have the sound alone. You say you trusted Nismo parts, I would say that I trust K&N. Different strokes for different folks, but I am very happy with this mod, recommend it to friends and prefer this over the stock airbox, but that's just my humble opinion.

 

After putting 600-700 miles on the car I felt that I had enough experience with the K&N that I would be able to judge whether the CAI actually did something positive for my driving experience. I had some time today to mess around with the car so I put the stock airbox back in the car and went for a drive.

It's no contest, the K&N CAI makes the car more fun to drive! In addition to the increased sound benefit I really think that the car is more responsive to throttle input. With the stock airbox the Sport Mode feels like Normal mode with CAI installed. The Normal mode with the stock airbox feels downright sluggish.

With the K&N installed the car makes me want to push it and wring out every gear and drive hard! With the Stock airbox I feel like all the car wants to do is drive in a casual comfortable mode.

So the K&N is going back in the car tomorrow. I'm sold. It really is a good thing!

 

Awesome Follow up!! So glad to hear this and it's interesting to read and compare your 1st day impressions with how it feels a few months later and switching back to the stock original air box. At first I could tell in your previous post that you were a bit skeptical, but I knew it would take some time for the ecu to remap all the fuel curves. Now that you are use to the sound and performance improvements its nice to hear your thoughts on going back to stock. So funny, because I almost put my stock airbox back on this weekend just to make sure I was not crazy

In the end I would hate to steer any one wrong with a recommendation. So I am so glad you are happy with it! It really does transform the car and makes it more enjoyable to drive!

BTW, did you notice any sound difference between your coffee can AEM filter and the K&N conical filter??

 

You are 100% right, I was skeptical (I spend a lot of time on Rennlist and the 997 forum is a very skeptical place about all mods, not just this one) but I did my Internet homework and felt it was worth a shot to try the CAI. I am glad I did. One of the major reasons why I went for it was your easy going attitude about the product. The no pressure "Hey it works for me and I am happy with my CAI, so if you are into trying it go for it!" style is a refreshing break from the often times combative style we see on car forums.

I never got around to putting on the K&N filter! Maybe I'll give it a shot tomorrow....

Another thing I noticed, and this might sound strange, is that the car seems easier to shift aggressively with the CAI installed. I'm not as jerky with the clutch engagement on high RPM shifts. I have no idea why this might be, it may be in my head. Anyway I'm happy with the product and thanks again for introducing it to me!

-Mike B

 

Your shifting may benefit from the better throttle response at high rpms. Meaning it may be easier to rev match or hold a certain rpm while shifting with the better air flow. Who knows, I am just guessing, but either way I am glad you confirmed my impressions and saved me the time of trying out my old air box .
After this mod I have never had the desire to go back to the stock airbox.

 

I reinstalled the CAI this morning and put in the K&N filter. The car now feels much better and the stock airbox is now permanently retired to the shelf in the garage.

The K&N filter has a slightly higher pitched howl than the AEM but the overall sound is the same. The AEM is more barrel shaped and at high RPMs it has more of a hollow sound than the K&N. I'm going to keep it on for a month and then switch back and see if I notice anything else.

 

First off, thanks for sharing qikqbn. Videos and details provided are very nicely done.

About the K&N CAI, I'm skeptical as well. rodh makes a good point that why would Porsche leave 10-15 hp like that? I didn't make the connection earlier but I'm sure it's related to decibel requirements. The sound clips clearly show how much louder a CAI increases decibels.

With that noted, unless I missed it, does this have an aftermarket or modified exhaust?

 

It's just the stock exhaust. It's well known that ALL car manufacturers leave room on the performance table because of many different factors that range from smog requirements for each country, sound, poor fuel quality, extreme temperatures, humidity and fuel economy. So there is a need for manufacturers to play it safe in some areas.

 

Nice! The CAI will be like 2 mods in one.. improved engine note and better intake! thanks!

 

Cool,thanks for doing that comparison! Interesting to hear how the shape of a filter also plays a role in the sound and acoustics.: keep us posted on your comparison