TxRLX

The K&N website does not list an air filter for the RLX so I contacted them only to be told that there was not enough demand right now. Has anyone found a quality hi flow air filter that will work on our model?

CFoote

Personally, I'm not a fan of K&N filters on cars with Mass Air Flow sensors. After a while the oil can actually accumulate on the wire in the MAF sensor and it can cause all sorts of problems.

justnspace

iTrader: (1)

Also, Acura engineers their intake systems pretty well. they have not left any HP on the table.

in their past cars, like the TL and RL, it is in fact a cold air intake system which draws from the bumper.
the OEM air filter, in past cars like the TL and RL, outflows the throttle body at WOT.
it would be silly of them not to implement the same kind tricks found in their previous cars.

this means you are not achieving anything extra by going to a K&N filter.

TxRLX

I've used K & N drop in filters in my last 3 cars and never had a MAF problem. You're right though, if you over oil them when cleaning then they can "bleed" on to the MAF wire and throw a code. However, the difference in performance is noticeable, the engine breathes better and I will only spend about $55 for a K&N vs $150. for an OEM or Fram over the life of the car. But in the end, the car is for my wife who will not notice the difference so it shouldn't really matter I guess. Thanks for letting me vent.

BWPaterson

I too have always used K&N air filters and also registered my desire for one for RLX with manufacturer. Hope they finally make one.

George Knighton

I suppose that as always it will remain a matter of opinion whether one or two HP is worth a possible degradation in air filtering.

There's almost always something that can be done, but people assume that the car won't stop improvements after a certain point because the car might believe that something is wrong and not maximize the extra air it's getting by richening the fuel mixture and advancing the spark further.

Were you around far enough back to remember the Mugen intake design for the B Motors in the DC2 ITR?

A completely stock B Motor realized gains, better gains than anybody else's intake, because the (very expensive!) Mugen intake was able to pressurize the air a little bit when the car was moving. This gave the driver the impression that he had quite a bit more power from like 45 mph because of his perception of much better throttle response.

But even removing the "perception" issue and whether there is a way to quantify it, owners of those cars way back then were able to demonstrate gains on dyno tests with B Motor DC2 ITR that and no other changes made to their stock motors, and without the car moving to lend the throttle body response to the driver's perceptions.

The performance of this intake was demonstrably good enough that when people built their B Motor configurations with other improvements, the Mugen intake remained the famously most popular idea to use for your B Motor builds.

As the life of the motor carried on, other people were able to produce intakes that appeared to capitalize on power and provide the perception that the power was usable by being able to pressurize the air at speed enough that the driver's perception was that his car was stronger.

But a lot of this perception was just because the throttle responded better at higher speeds in higher gears, mostly simply because of the pressurized air.

George Knighton

What I meant by this is that in modern cars, to some extent that we do not know for sure because it varies depending on how it is programmed, the same computer system that degrades power when necessary to be able to handle bad quality fuel, or to be able to handle occasions that the owner can only find 87 octane instead of 91 octane, will be able to detect when something has changed that will allow it to give you more power.

For example it's entirely possible that continued use of 93 octane will eventually give your car a little more power than you would have with the continued use of 91 octane.

It's possible, but not certain.

And this same system could detect when you have better airflow, and it might very well richen the mixture and advance the spark to give you more power, while remaining active enough to intervene if it notices detonation.

This is why people could detect an increase in power, safe power, when just slapping a Mugen intake on a B Motor DC2 ITR. The car would notice the air flow, and to a small extent richen the mixture and advance the spark to take advantage of it.

You're not talking huge gains here, but in those days it was a 10 HP difference that was easy to document without making other changes.

That was probably a fairly unique thing.

In those days companies like Mugen were treated like they were a part of Honda sort of like what HPD is now. Spoon and ComptechUSA were treated similarly. Ichishima's crazy, by the way. In a good way, but crazy. :-)

Maybe it's possible that the 2014 J35Y4 will respond to 93 octane, and maybe it would respond to a change in air flow over an extended period as it adapts itself automatically.

But I suspect that in 2014 we will see more limited gains than those we used to see, primarily because Honda is paranoid about its CAFE and emissions standards and I don't think that programmers and engineers would allow so much modification these days. What used to be a 10 HP difference back in the B Motors days might very well be a 3 HP difference in the 2014 DI J Motor days, which makes it far less an economically feasible, far less a reasonable thing to be doing.

As usual, however, this is just one dumb old man's opinion.