OEM intake vs k&n

[Jinks]

So I bought the car with the k&n intake already installed. I just went back to Oem with a downforce scoop because the supercharger kit I am installing I do not want hot air being drawn into the engine.
Now, I know all about the benefits of the well designed Oem intake and how dyno testing proved no other intakes outperformed it by much, but I swear, my car pulled way harder on the hwy on ramp then it does now with Oem and downforce scoop. It was kind of a big let down. But still, I wanted the Oem so.
Maybe it is because the air has less way to travel into the engine I don't know. All I can say is, the k&n intake pulled a lot better plus when you hit vtec, you damn sure knew it!
Just thought I'd add my thoughts to someone looking into a k&n.
thanks.

 

[naaman]

I had a K&N on my Camaro when I bought it. Those things are such a PITA to maintain that after a while, they wind up becoming an airflow restriction, rather than a benefit (keeping them clean takes far more work than it's worth, IMHO). I once tried to merge from a stopped lane of traffic into a moving lane of traffic in the car. Hit the throttle with some gusto, and the car just bogged for a second. "That was dangerous," is what I thought to myself. That day, I went out and got a Fram paper filter. Oh my goodness! The car came back to life immediately. Torque available from idle all the way on up. I have not considered a K&N since, and likely never will again.

Now, my car was NA so I don't know what the difference would have been had it been SC'd, but with heads/cam on the Camaro, I'm liking the paper filter just fine.

 

[darock]

I just had a dirty K&N insert in my OEM airbox when I got the car. It always had a strange behavior when pushed hard. Sometimes it would just not react to the gas pedal input. Replaced the K&N with a totally basic aftermarket air filter -> problem gone and never appeared ever since.

I don't like K&Ns since I had a air mass sensor go bad on my diesel daily because of the filter oil.

The thing you experienced is probably more related to noise and a reduced low end torque. First a noisy car feels more sporty, we all know that. Second, if you loose torque down low due to the K&N the upper rev range feels more exciting. An engine that has a totally linear torque curve most likely feels a little boring. Toyota engines are a perfect example for that.

Bernhard

 

[nsxtasy]

The thing you experienced is probably more related to noise and a reduced low end torque. First a noisy car feels more sporty, we all know that. Second, if you loose torque down low due to the K&N the upper rev range feels more exciting.

+1

I had the same experience when I used a K&N cone filter on my NSX for a while. It had a louder whoosh sound that could easily be perceived as being faster, due to the sound rather than any improvement in actual acceleration.

 

[Jinks]

Totally understand. But there is a road marker after my hwy on ramp where I gun it. With the k and n intake it hit that marker almost 5 mph faster. But yeah the k and n coupled with a mass air flow sensor is no Bueno.

 

[solidol]

It's all bs unless you dyno it. And do it right too. Oem is the way unless itb

 

[naaman]

I just had a dirty K&N insert in my OEM airbox when I got the car. It always had a strange behavior when pushed hard. Sometimes it would just not react to the gas pedal input. Replaced the K&N with a totally basic aftermarket air filter -> problem gone and never appeared ever since.

I don't like K&Ns since I had a air mass sensor go bad on my diesel daily because of the filter oil.

The thing you experienced is probably more related to noise and a reduced low end torque. First a noisy car feels more sporty, we all know that. Second, if you loose torque down low due to the K&N the upper rev range feels more exciting. An engine that has a totally linear torque curve most likely feels a little boring. Toyota engines are a perfect example for that.

Bernhard

+1

I had the same experience when I used a K&N cone filter on my NSX for a while. It had a louder whoosh sound that could easily be perceived as being faster, due to the sound rather than any improvement in actual acceleration.

Interesting... I tend to have the opposite experience: the noisier the engine/exhaust is, the faster I expect the car to be... when it doesn't measure up, it leaves me with that diesel-work-truck feel. A whoooooole bunch of noise, and no zoom. When using the butt-dyno, the quieter car is always more satisfying (like the engine makes a bunch of power/torque at throttle tip-in).

 

[Jinks]

To be honest, the noise is exactly the same. Before and after. Unless in vtec engagement. I think some people my miss my point here. The old intake felt like it pulled harder. But hot air in the engine it does suck in. I am only giving my unadulterated experience between the two. Not to argue which is better, blah, blah.

- - - Updated - - -

Supercharger goes in the car next week. Maybe I will dyno it with the Oem and Df scoop on the same dyno at driving ambition where it did 251 peak. It will cost but it is good to know and seeing is believing!

 

[B2FiNiTY]

You should dyno the supercharger setup + oem intake vs supercharger + k&N intake.

 

[Jinks]

Good idea! Just boxed up the intake to take to Shad along with the car.
For other fellow primers, I come in peace! I find these threads fun and very informative. Please don't jump a gun and argue. Life is far too short.
Thank you.

 

[B2FiNiTY]

I wouldn't be surprised if the hot air intake made more power. I've seen this happen on honda b-series motors that were supercharged with the jackson racing setup.

 

[Hapa88]

This has been discussed before. IMHO, the stock intake (maybe with the Downforce intake scoop) is the best for N/A. It is perfectly tuned for the N/A application with atmospheric pressure.
However, when you supercharge the system, you're forcing MORE air into the engine than the OEM intake was originally designed to. Infact, you're drawing 6-9 psi MORE than the original intake system was designed for. All dyno tests that prove the OEM intake was superior to other intakes were tested on a N/A car. My guess, is that the OEM system is not designed to accommodate the extra 6-9 psi and associated airflow of the supercharged system. Therefore, I would suspect the K&N system being superior to the OEM airbox for supercharged applications (yet to be dyno proven).
User LMR had Dyno tests showed his B-Line motorsport intake performed better on his supercharged NSX than the OEM intake.
http://www.nsxprime.com/forum/showthread.php/143702-My-new-B-Line-Motorsports-True-Cold-Air-Intake

 

[Mac Attack]

If you liked the noise with the K&N and you think it was faster, just go ahead and run the K&N!

Just make sure to keep it cleaned and appropriately-oiled (not too little and not too much).

Dave

 

[Jinks]

If you liked the noise with the K&N and you think it was faster, just go ahead and run the K&N!

Just make sure to keep it cleaned and appropriately-oiled (not too little and not too much).

Dave

I kept the k&n clean every 500 miles. The Oem coupled with the Df scoop and uni filter which I now have and can maybe never be driven again in the rain, will be cleaned twice as much. But thank you for your input all of you. This is why it is called a, " discussion" and not an argument thread. But I am curious as to what numbers each will throw down under boost. Which I "will post" just for the fun of discussion and not to prove a point. Happy nsx motoring guys!

 

[racer9x]

Always good to conduct these type of comparisons on the dyno to actually clarify any suspicion, please keep us updated with you're results (but history points at:scoop and OEM beating the hot air breathing K&N).

 

[Jinks]

Very good point. If I may though add my own? All the dyno charts are old and the ctsc has been revised many times.
The kits are more modern with more efficient blowers which reduce intake temperatures and lower the amount of force/hp needed to turn the blower. It will be fun for me and also to possibly help out in the nsx community to see what is what. If I am wrong, so be it. If right, no boasting needed. I am just the kind of guy who needs hands on learning as I am a mechanic by trade and not a book learner. I will post my dyno charts of each when Shad is finished. I just never see any dyno charts with anything but ct, gruppe m, Mugen, or Oem. Also, gruppe m is just a fancy carbon Kevlar version of the k&n intake which has been proven to have very high torque at low rpm coupled with a blower which I am putting my money on being due to the short intake length. But that is only my own assumption and thoughts. Cheers.

 

[JD Cross]

Intake tuning and efficiency is something Honda knows a great deal about.
It took some time before the NSX community came back to the OEM intake as an efficient system.
I'm sure the harmonics are much different on an engine with a supercharger spinning away between the intake and the valves.

Where did you find the data on the GruppeM/K&N intake with supercharger high torque numbers?
Why is the short intake length significant as opposed to a long intake?

 

[Jinks]

The data, I reviewed was here on prime about how a gruppe m supercharger has much higher torque at low rpm versus a ct supercharger with ct intake. For what it's worth when I asked Shad to dyno the two, he told me I would see zero difference on a dyno. So, when Shad speaks, I listen and shut up. Therefore My opinions as posted previously are still just speculation up in cyberspace. I would have liked to have dyno sheets to review myself but according to Shad, it is a waste of time. So, still there remains no specific data between the two. It remains a personal preference.
Thanks.

 

[JD Cross]

The data, I reviewed was here on prime about how a gruppe m supercharger has much higher torque at low rpm versus a ct supercharger with ct intake. For what it's worth when I asked Shad to dyno the two, he told me I would see zero difference on a dyno. So, when Shad speaks, I listen and shut up. Therefore My opinions as posted previously are still just speculation up in cyberspace. I would have liked to have dyno sheets to review myself but according to Shad, it is a waste of time. So, still there remains no specific data between the two. It remains a personal preference.
Thanks.

Does this mean that Shad is telling you there is no difference between an oem intake and a K&N intake?
One make more noise than the other and that's it?

 

[naaman]

Perhaps it has to do with a sort of "ram air" effect? Or maybe a CAI effect (if the car isn't moving, it's drawing in "still" air, so it loses the benefit of fast moving cold air)? A dyno would produce no data if that is the case. Another factor might be that the car is not dyno'd at a low enough rpm to show the difference (many times, I see dynos starting at around 3k).

 

[HDA]

My car came with it.
After a week it was in a landfill somewhere in Texas.

 

[Jinks]

Update,
Even though I feel like the k&n pulled harder in my opinion, after driving the car a bit more with the downforce scoop/ Oem intake the sound is definitely growing on me. It kind of makes a sound like a growling Panther. Kind of cool.
Too bad a car can never be measured in hp while moving. But still with the uni filter I get that hissing sound when ignition is cut as did the k&n. But I guess that will not matter soon as the ctsc will make its own noises. I'm going to keep the k&n just in case I have to drive in heavy rain if we ever get that again in California.

 

[Thanhnsx]

I would like to share my experience at Sacramento Raceway drag strip in 2010 with these filters. When running OEM my best time was 13.603. I went back a month later with a K&N (flat) dropped into the OEM box and my best time was 13.323. So IMO, the K&N is definitely better than OEM. I now have a custom CAI and it pulls much faster. But then again, every car is different.

 

[Hapa88]

I would like to share my experience at Sacramento Raceway drag strip in 2010 with these intakes. When running OEM my best time was 13.603. I went back a month later with a K&N drop in and my best time was 13.323. So IMO, the K&N is definitely better than OEM. I now have a custom CAI and it pulls much faster. But then again, every car is different.

So many variables in that comparison, it's not even funny...

 

[jwmelvin]

So many variables in that comparison, it's not even funny...

That's odd, I found it very amusing.