Stock air box vs. K+N CAI
03-24-2020, 01:08 AM
#46
Rennlist Member
K&N did a GREAT job at it! Made so much money off people who think the "5 HP gain" is noticeable. I fell for it!
Same goes for "drilled and slotted" rotors. The 996 never needed these rotors on them from the factory. They only did it to help sell cars. Race cars have them, so putting them on passenger cars tricks people into thinking their car is a race car. Forget the fact that 99.9% of the cars will never be driven to actually use them.
I know it's rare, but how many times have we heard someone brag about how much more HP they have or someone who loves to run down the list of their mods. K&N is just one company to profit handsomely off those people. Kudos to them!
"Horsepower sells cars" and aftermarket parts!
03-24-2020, 02:14 AM
#47
Three Wheelin'
I partially agree,, at "normal" engine performance levels the difference from a K&N or really any other filter is mice nuts..
However,, a 406 sprint motor on methanol with Hillborn injection at 15:1+ compression...
But we are talking about a air filter that is almost as big as the engine.. Paper system vs K&N vs ITG the
K&N out powered the ITG on the engine dyno at the flywheel by about 8 HP,, but the
Foam ITG was SOOO much easier to maintain.
Does 8HP matter when your moving north of 800.. Not so much IMHO..
the K&N didn't muffle the intake as much,, so sound-wise it won.
However,, a 406 sprint motor on methanol with Hillborn injection at 15:1+ compression...
But we are talking about a air filter that is almost as big as the engine.. Paper system vs K&N vs ITG the
K&N out powered the ITG on the engine dyno at the flywheel by about 8 HP,, but the
Foam ITG was SOOO much easier to maintain.
Does 8HP matter when your moving north of 800.. Not so much IMHO..
the K&N didn't muffle the intake as much,, so sound-wise it won.
03-24-2020, 02:50 AM
#48
Rennlist Member
I partially agree,, at "normal" engine performance levels the difference from a K&N or really any other filter is mice nuts..
However,, a 406 sprint motor on methanol with Hillborn injection at 15:1+ compression...
But we are talking about a air filter that is almost as big as the engine.. Paper system vs K&N vs ITG the
K&N out powered the ITG on the engine dyno at the flywheel by about 8 HP,, but the
Foam ITG was SOOO much easier to maintain.
Does 8HP matter when your moving north of 800.. Not so much IMHO..
the K&N didn't muffle the intake as much,, so sound-wise it won.
However,, a 406 sprint motor on methanol with Hillborn injection at 15:1+ compression...
But we are talking about a air filter that is almost as big as the engine.. Paper system vs K&N vs ITG the
K&N out powered the ITG on the engine dyno at the flywheel by about 8 HP,, but the
Foam ITG was SOOO much easier to maintain.
Does 8HP matter when your moving north of 800.. Not so much IMHO..
the K&N didn't muffle the intake as much,, so sound-wise it won.
03-24-2020, 11:06 AM
#49
Rennlist Member
Someone probably got tired of buying the Bosch MAF only to have it fail. That's due to being covered in oil, and fouled from the open element air filter, and the oil they treated it with.
There's NOTHING good that come from these intakes. I am not saying this because I am a purist, I am saying it because I have 18 years of direct experience proving they are inferior to a stock airbox.
There's NOTHING good that come from these intakes. I am not saying this because I am a purist, I am saying it because I have 18 years of direct experience proving they are inferior to a stock airbox.
03-24-2020, 11:16 AM
#50
Rennlist Member
My .02... I have a 2001 996 C2 Cab with approx 87,000 miles on it. I purchased it about a year ago and one of the first mods I did was to install the IPD Competition plenum, 82mm GT3 throttle body and a K&N CAI. I also got a tune installed and swapped the exhaust for a complete Top Gear system including the 200 cell sport cat x-pipe. I also replaced the original MAF sensor and the O2 sensors both pre and post cat. Very happy with the sound, especially from 5K to 7K rpm, but I felt like I lost some low end torque and smoothness as the engine winds up.
So today I re-installed the stock air box, but with the silicone tube (air box to TB) and rubber cap (to block off the air box muffler) from IPD, along with a new BMC air filter. Took it for about an 80 mile drive over a mix of expressways and two lane roads and I gotta say that overall the stock airbox with the above mods is superior to the K&N set up. Smoother response, no hesitation on the way up and still sounds awesome at WOT. No discernible change in the butt dyno IMHO.
I ended up wrestling with the new silicone air pipe a lot more than I expected since it is very stiff and frankly seemed a bit too long, but I was able to get everything seated and tight.
So I guess I now have a K&N CAI to put on ebay...
So today I re-installed the stock air box, but with the silicone tube (air box to TB) and rubber cap (to block off the air box muffler) from IPD, along with a new BMC air filter. Took it for about an 80 mile drive over a mix of expressways and two lane roads and I gotta say that overall the stock airbox with the above mods is superior to the K&N set up. Smoother response, no hesitation on the way up and still sounds awesome at WOT. No discernible change in the butt dyno IMHO.
I ended up wrestling with the new silicone air pipe a lot more than I expected since it is very stiff and frankly seemed a bit too long, but I was able to get everything seated and tight.
So I guess I now have a K&N CAI to put on ebay...
03-24-2020, 12:31 PM
#51
Instructor
Hey Bill, yeah I was thinking that might be the problem... I have a 2001 996 with a 3.4 and perhaps the elbow was intended for another year/engine. Was looking at the model-specific one on FSI's website and am considering that one since the air box is sitting up a little bit even though it is bolted in... I may try trimming this one down to match the stock elbow first.
I also tried installing the stock elbow (with the orange cap mod) but wasn't able to get it to stretch onto the 82mm TB.
Thanks for the suggestion!
I also tried installing the stock elbow (with the orange cap mod) but wasn't able to get it to stretch onto the 82mm TB.
Thanks for the suggestion!
03-24-2020, 01:29 PM
#52
Advanced
03-26-2020, 05:03 PM
#53
Addict
Rennlist Member
Rennlist Member
When I purchased my 996, it came with a new K&N cold air kit uninstalled. So I installed it and got one code, cleared the code and it never came back. I like the look and sound of it compared to the original, and it has a sheet metal box/shroud that isolates the conical air filter from the rest of the engine compartment and vents directly to the original cold air snorkel. I dig it and its not causing me any problems, so I'm keeping it!
03-26-2020, 05:11 PM
#54
Addict
Rennlist Member
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03-27-2020, 04:21 PM
#56
Instructor
Here's a video on the dyno test of a 997 3.6 tiptronic that shows the "CAI" is actually an HAI "Hot Air Intake" and loses power. I had one of these on my '02 C2 and did like the sound, but replaced it with a stock intake after reading many reports about the stock intake working better.
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Mike Murphy (03-27-2020)
03-27-2020, 04:38 PM
#57
Former Vendor
https://www.youtube.com/watch?v=mc9c07qCuKY
Here's a video on the dyno test of a 997 3.6 tiptronic that shows the "CAI" is actually an HAI "Hot Air Intake" and loses power. I had one of these on my '02 C2 and did like the sound, but replaced it with a stock intake after reading many reports about the stock intake working better.
Here's a video on the dyno test of a 997 3.6 tiptronic that shows the "CAI" is actually an HAI "Hot Air Intake" and loses power. I had one of these on my '02 C2 and did like the sound, but replaced it with a stock intake after reading many reports about the stock intake working better.
People never listen. Thats ok, they pay for it later "even though their's runs fine with it".
Look at MAF values before and after, fuel trim before and after, and then wait for the trend data. When exposed to these cars from all over the planet, and the engines are all you do, you connect the dots. Sometimes it takes years, but the dots turn into plots.
03-27-2020, 05:55 PM
#59
Rennlist Member
https://www.youtube.com/watch?v=mc9c07qCuKY
Here's a video on the dyno test of a 997 3.6 tiptronic that shows the "CAI" is actually an HAI "Hot Air Intake" and loses power. I had one of these on my '02 C2 and did like the sound, but replaced it with a stock intake after reading many reports about the stock intake working better.
Here's a video on the dyno test of a 997 3.6 tiptronic that shows the "CAI" is actually an HAI "Hot Air Intake" and loses power. I had one of these on my '02 C2 and did like the sound, but replaced it with a stock intake after reading many reports about the stock intake working better.
With that said, thinking that any of these mods will increase power, and the increases in power actually be enough to actually feel is where there's a disconnect. Most people dont realize that as base hp increases, the amount of hp increase needs to be greater to be felt.
20 hp increase on a 4 cylinder is not the same as a 20 hp increase on a 6 cylinder. HP increases is all relative.
Hoping to get power increases out of these engines will only leave the owner disappointed and less money in their bank accounts. There aren't any worthwhile bolt-on modifications for the M96 that the butt dyno will detect.
Now if your main goal is just to make the car sound better, intake and exhaust mods are a good choice.
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Porschetech3 (03-27-2020)
03-27-2020, 07:01 PM
#60
Rennlist Member
40th Steve - Reference Streather, the difference between the 3.6/M96.05 and 3.8/M97.01 boxes, other than the plate, was the 3.8 box had a vacuum resonance flap installed. Air flow-wise, I’m not sure. Both 997 boxes are more air tight (keeps intake air cooler) than the older M96 box and visually look to have more interior volume.