Hi all, does anybody have thoughts on the fitment of a K & N filter in place of the standard filter. Are there benefits over the standard filter given that it costs circa £50.00. I read conflicting results from the fitment of the K & N unit. Dave.
Same question from me really.
I’ve a Pipercross filter fitted. My snake oil suspiciousness says it shouldn’t make any real difference but my buttometer says the car is ever so slightly more responsive. Cheaper than a K&N too plus you never have to buy another filter again.
Thanks for that.
I think any power gain is negligible, maybe it helps the engine breath better if enhancing the exhaust and having the ECU remapped? I have the K&N panel filter on my MK3.5 I would say that it does improve the induction noise, you do get a slightly raspier sound when accelerating hard. After a year I removed the filter for inspection half expecting it to be pretty much spotless. Actually it was pretty grotty with leaves and dead bugs so cleaned it with the K&N kit then reinstalled.
Nice to know it should last the life of the car and there’s a bit less rubbish going in landfill as a result.
No difference at all apart from its reusable
Well, maybe it was the dense 3 degree air but my 2.0 3.5 was absolutely flying yesterday.
Back in the Summer, I fitted a Pipercross filter and opened the upstream half of the airbox by drilling holes between the ribs. It sounded fantastic but it was too much for my missus, so I cut some closed cell foam to fit between the ribs so I could have them open or closed in a moment. I have also been using Tesco Momentum to take advantage of the knock sensor to give more ignition advance.
For my last fuel stop, I treated the car to some V Power, which did feel even better. However, yesterday I went for a blast on my own but following daughters Fireblade, so I removed all the foam, going from 1 hole to all open.
I’ve never tried fully open with V power before but with just me in the car and little fuel in the tank, it sounded and felt fantastic.
All subjective of course but the next fill is going to be VPower again…
Manufacturers spec the air filter to have redundant capacity at the service interval, the OEM filter is not a restriction on performance. It’s also the best filter as far as air cleanliness. Only if you increase the need for considerably more airflow will you need to put in something different, such as fitting a turbo.
What you will get is more intake noise so it sound better/quicker. You get more benefit from working on the exhaust side.
I’ve used K&Ns for years on both car and bikes, certainly, cleaned up throttle response compared to the paper one in the box, but a new standard one might have done too. the one in there wasn’t a mazda branded one, but it didn’t look knackered and had a 2017 date on it so can’t have been in the car that long or that far looking at the service / mot data I got with the car
A chain is only as strong as its weakest link.
If the airbox is a restriction, the filter might make little difference.
Did you try just the panel filter or even no filter without the upstream half of the airbox?
It would be interesting to see what difference, if any, that might make.
It was/is a common mod on the Ducati SS to run it with no airbox lid. In fact, K&N supplied a frame to secure the filter with no lid in place.
I have just swapped the standard (new) filter in my 2.0 ND for a pipercross one. I can say that I noticed no difference whatsoever. However I feel good that I swapped it!!!
We did do a test with no airfilter at all, zero increase.
There are only losses to be made, both with power and filtration. You can practically read a book through an aftermarket filter.
A bit O/T and not really of much use, but we once took a std back box off and saw +5bhp.
Why I say it wasn’t of much use really we should have put a different one back on to see what a difference that made, but we didn’t have one at the time and time is money when you’re at the dyno. It does show what very small power figures you’re playing with though.
Back in the bad old days of £25 auction bangers my best one was a Farnham Estate Zodiac. That had an oil-bath air cleaner which looked like a dustbin occupying a large part of the engine compartment.
Removing all the mesh internals and putting some ‘fresh’ (ie ex-engine) oil in the bottom, so it just had a slight labyrinth and a sticky dust trap, put up the top speed from the needle pointing at 100 to easily going out of sight (110?), and the mpg went from 18 to 22 (it made no difference how the car was driven). I have no idea what the real speed was with the 185 x 13 SP Sports instead of the specified 6.70 x 13 cross-plys.
I could have put a Derrington branched exhaust on for much better gains, but that would have cost me more than the car did.
I did 20,000+ miles in that car with effectively no air cleaner.
999to5
As you said what probably makes a larger difference is cold dense air and good quality petrol. An empty boot and half a tank of fuel will all add up to more performance. I’m happy with the K&N but didn’t expect it to improve the performance at all. Having said that a friend of mine has a 1.8L NC and swears that fitting the K&N helped the engine to Rev more freely. Highly subjective the only change I noticed is the better sound from the front.
As I understand it (from reading many posts and articles) that unlike the NA and NB the NC intake system is pretty good and doesn’t introduce warm or turbulent air. I read BBR recommend leaving the standard NC air box alone as changing it for cones etc etc doesn’t add any power.
I read years back…the NC intake was pretty much as “ram air” as possible anyhow?
Thanks Dave
Good info thanks Dave
I fitted a K & N PS1008 to my NA at the last service. Unfortunately it seemed to cause an unexpected problem and I have reverted back to a Mazda 9A filter from MX5 Parts.
The problem seemed to be that it would allow oil to drain out of it and as the car is not used daily the valve-train would be noisy on start-up. This was a cause for concern, hence changing back to the original fitment which doesn’t seem to empty of oil, however long the car has been standing.
To check what might be happening, I let the car stand a week before removing the filter. All of the oil had drained out of it, confirming my suspicions.
It was returned to K & N for examination and they found no fault with the non-return valve or any other aspect of the filter.
K & N were most helpful and they have replaced it with a HP 1008. However, I now suspect that with the filter being horizontal, oil was seeping back through the high flow filter media, so the HP 1008 will offer no improvement.
I’m sure the K & N filter is a quality product – just not suited to my NA and I’ll be using a 9A in future.