Nissan 370Z Forum - 370Z K&N Dual Air Filter

Nissan 370Z Forum (http://www.the370z.com/)

- Intake/Exhaust (http://www.the370z.com/intake-exhaust/)

- - 370Z K&N Dual Air Filter (http://www.the370z.com/intake-exhaust/5660-370z-k-n-dual-air-filter.html)

Quote:

Originally Posted by Robert_Nash (Post 94105)

Even if I asked; they very likely wouldn't tell me.

Even if they told me, I probably wouldn't be allowed to tell anyone else.

If I did tell anyone else I'd probably (and appropriately) be fired.

So I think it best I shut up now. :)

I think the confusion is stemming from airflow vs charge temp. The opinion you cited only addressed airflow. While stock airflow may be adequate, it's drawing hot engine compartment air. The only intake which has showed significant improvement so far (Stillen G3) moves induction in front of the radiator, outside the engine compartment entirely.

It's not really about intake airflow for the 370z, so it misses the point.

Quote:

Originally Posted by dawankler (Post 94178)

....And Robert, in rereading your earlier posts you DID say you didn't think it'd provide appreciable performance gains unless they were in tandem with FI or extreme modifications. I guess it just depends on your price/performance ratios, but there's been a number of posters here with proven gains (10% isn't uncommon so far) by just upgrading the airflow.

Well, I likely didn't express it well but what I was trying to convey is that an engine, in otherwise stock form; doesn't really need additional air flow and/or isnt' really going to benefit from it. By extension, then, if you start opening up the exhaust side of the equation then more air flow in would likely be a good thing! :)

Quote:

Originally Posted by Robert_Nash (Post 93920)

Let me state for the record that I'm not an engineer or mechanic or anything close; my expertise is accounting, finance and IT.

BUT...

I have learned to realy on people that are engineers and mechanics when it comes to engineering/mechanical issues (and I have on numerous occasions stayed at Holiday Inn Express hotels).

SO...

I've had conversations about this very issue with both Nissan engineers and with Doug Stewart (Doug owns Crawford Z Car Service in Nashville and has made his living repairing and racing Zs and Nissan's in general for over 30 years; his shop is also were we [Nissan] takes vehicles form the heritage collection for work. I won't advertise his website here but Doug has developed many performance parts for Zs including, of course, the 350 and I can only assume he is working on parts for the 370) and as Doug's shop sells and installs intake kits he has a vested interest in encouraging their use.

So with that said and after that long introduction...what Doug and Nissan engineers have told me is what I mentioned above; that the air box set-up on the 350/370 is more than adequate to feed the engine all the air it can handle in anything near stock form and using a low restriction air filter is as much of an increase in air flow as the engine can use/need.

Certainly, if you are going to start dong major modifications that will give the enging a greate need/ability for air then that's a different equaiton but putting an intake on the stock engine does not get you anything; at least not enough of anythign to justify the expense.

Now; I've nothign against intake kits and they do add a nice look to the engine and most people, including me, think they give the intake a nice "sound" but if you are lookinf for a measurable HP/Tq increase it seems that there are better ways to spend your money.

Disclaimer: nothing I've said above should be construed as offering mechanical advice nor is it the official position of Nissan North America or Nissan Motor Limited; no warranty is either expressed or implied...you sould should consult professionals in your area who can evaluate your specific circumstances...Live Long and Prosper!!!

Well, they've worked on nothing but Nissan's for thirty years, and Nissan's are all they work on. I'd accept their word , before a lot of other companies! A friend of mine who lives in Clarksville, took off his intake, and went back to stock. He stated that the sound was great, but no performance benefit.

Quote:

Originally Posted by 2bits (Post 94179)

Incorrect. The stock system is sealed to the thru ports at the Radiator support. ALL air is ingested from outside the engine bay, just like the Stillens. IAT (intake air temps) run only 8-10 degrees higher than ambient at steady cruise, so the Stock box is pretty well designed to start with..

Quote:

Originally Posted by Modshack (Post 94208)

Cool, I stand corrected. However, I'm a bit puzzled at the G3's success now.

Quote:

Originally Posted by 2bits (Post 94221)

Cool, I stand corrected. However, I'm a bit puzzled at the G3's success now.

I can't speak for Stillen, but from what I've read they've done a fair amount of research into the long tube design. There's some increased (very smooth) flow, Lottsa filtration area, and relatively cool air from in front of the radiator. In addition, the MAF signal is probably altered slightly as the tube ID's are slightly different than stock, resulting in a slight leaning and more power. There are lots of factors, one of which is that most Dynos seem to have been done with the nose off. which enhances the end result some. I've been building airboxes for Audi's for 8 years now so I've got a little experience messing with them. Some of it's science, some of it's luck, some of it's a sympatico relationship between engine designs and the CAI's that work well on them..

Mine was done with the nose on, just for the record. ;) +14.7whp on Forged's Dyno Dynamics.

Quote:

Originally Posted by Modshack (Post 94208)

Yes...that that the air is taken as you describe is one of the reasons cited to me as to why intake systems, at least generally, don't give much benefit in the 350/370.

Thanks for stating it so clearly! :)

Quote:

Originally Posted by Josh@STILLEN (Post 93925)

While Nissan has definitely built a great platform, there are gains to be had from aftermarket products, including the intake system, our Gen 3 Intake having notable success in increasing horsepower, and making a noticeable improvement in acceleration along with transforming the sound from the intake, especially at high RPMs.

A quick search of the forums for dyno results on the Gen 3 Intake should give you some independent results from forum members here, some of whom have spent a small fortune for the good of the boards documenting their installs and resulting performance gains.

On the K&N side, we've been using these filters with our intake systems since the beginning, and sold countless panel filters, and have had exactly ZERO problems related to MAFs, oil, etc. K&N has been hit with a myriad of claims, most of which can be attributed to 'internet rumor', so much so that they set up a division and research arm within the company to attempt to combat these (largely unsubstantiated) internet claims.

Also keep in mind that normal cleaning procedures for panel filters is 50,000 miles, and conical filters used with air intakes is 50,000-100,000. We recommend 50,000 miles between cleanings. Even if gains are minimal on a panel filter, the convenience of not purchasing paper filters more than offsets the cost of the K&N, and in actuality, probably the Gen 3 Intakes if you consider the life of the vehicle.

And please allow me to add to this that if by chance some oil does get on the MAF wire. Just buy a $3.00 can of either MAF cleaner at NAPA or a can of electronic circuit board cleaner and spray the wire IN-SITU and let it dry naturally by air thoroughly . It takes all of 10 minutes to "wash" the oil off and everything will be back to normal.

Is there a wideband showing a/f ratio for these stillen graphs? It could be leaning it out like modshack said. I know from experience that the s/c Cobras can get very lean with the addition of a cai, and in some instances require a retune to be safe.

Quote:

Originally Posted by tstrick9 (Post 94554)

http://www.the370z.com/intake-exhaus...-vid-dyno.html

The second dyno graph shows A/F.

Modshack, since you do alot of intakes and have had your bumber off to do your diy intake air duct thing, would doing your diy mod and drop ins be just about as benificial as an aftermarket cai?

Quote:

Originally Posted by Zsteve (Post 222300)

Modshack, since you do alot of intakes and have had your bumber off to do your diy intake air duct thing, would doing your diy mod and drop ins be just about as benificial as an aftermarket cai?

Fang vents to the stock box should work fine...Drop ins are of minimal value though..

Quote:

Originally Posted by FricFrac (Post 93298)

...or get the Stillen G3 intakes for the best of both worlds ;)

:iagree: well worth the money and the performance gains isn't bad.

Quote:

Originally Posted by Triple's (Post 222771)

:iagree: well worth the money and the performance gains isn't bad.

I can't see putting on a Stillen G3 intake without also buying at the same time a less restrictive exhaust in order and a required custom tune to get the full benefit of the intake. I can think of alot of better things to throw away $3000 on that will not depreciate the moment it goes on the car.:rolleyes: