34 replies to this topic

[etrusco]

I used to do hundreds of miles a year on a pretty extreme track only MX-5 turbo, pushing some 240HP at wheels. Every time I took engine apart I would find grime and dirt all over my throttle body butterfly, using a K&N cone filter. After changing back to a stock filter inside an RX-7 box, The dirt was no longer present after the same amount of miles, circuit and time of year. Did u ever try any testing comparison K&N vs OEM? Maybe that would be a revelation for you Of course Ferari supply aftermarket exhaust after passing homologation, but like I already said It does not hinder engine longevity. I started saying that some particular filters have been tested against OEM and looked very bad, contradicting all advertizing claims made by K&N, then there are people that don't want to believe the independent test results, and want to keep using such filters, be my guest, free world.

[LazyDonkey]

So just to confirm these are tests that were carried out on a highly tuned turbo-charged mx5? Great, that will be of great insight to the guy who started this thread who owns a lightly stressed "astra spec rep wagon" 2.2 VX220.

Edited by LazyDonkey, 03 April 2006 - 03:04 PM.

[LazyDonkey]

Should point out i'm not actually looking for a fight merely trying to reduce some of the hysteria surrounding the "fitting a cotton panel filter will destroy your engine in minutes" faction.

[2-20]

There are interesting pictures on this link.
Stock and KN filters seen by a binocular.

HERE




For sure, the KN is more free flowing per square inch.

But the standard filter has more surface:

[etrusco]

Should point out i'm not actually looking for a fight merely trying to reduce some of the hysteria surrounding the "fitting a cotton panel filter will destroy your engine in minutes" faction. 

Hysteria?! I imagine you'll be having tea and biscuits after your dealership calls you about your premature loss of compression due to badly worn piston rings and valve seats...

By the way LAzyDonkey, I've given you my motivation for ditching my K&N panel, then cone filters from my cars and justified it with my personal experience with these filters, along with several links of exhaustive testing (Some very scientific) reporting detailed results.
What about you? I still haven't read why you believe they're so good...
Please don't paraphrase the "tuner magazine" blah blah about, deep macho burbling noises, impressive 5-10 HP gains across the rev band etc., I would like to know your reason for thinking it's the nirvana of air filters.
Oh, yeah forgot yours came with the car when you bought it, so someone already did the work and made the decision to install it for you.

Edited by etrusco, 03 April 2006 - 11:41 PM.

[2-20]

I suggest to read this interesting article (not VX related but ...)
And then to conduct your own pressure drop tests.

Read this

[etrusco]

Nice reading 2-20, I had to contend with many of these issues on my MX-5. Airflow is fluid dynamics, it's measurable,quantifiable and no black art, or esoteric stuff and it applies to every engine N/A or turbo. FLUID DYNAMICS WITH ABRASIVE MEDIUM IN IT, IS CALLED "EXTRUDE HONING"

Edited by etrusco, 04 April 2006 - 01:08 AM.

[LazyDonkey]

Oh dear its all getting a bit personal. For the record my original post was to correct one inaccuracy (AMM failure) and to point out that your chosen route (freeing up the air box) was not without its critics. I have never and will never state that the K&N is the nirvana of filters. As I stated in my advice to TedJ, the K&N makes a lovely noise but doesn't contribute greatly towards Bhp......the original point of this thread. I'm not an expert in filters nor engines, but if Courtenay and Rouche says the K&N is ok, then that's good enough for me. I think I'll be ok with the fact you think I'm an idiot for keeping it on

Edited by LazyDonkey, 04 April 2006 - 07:44 AM.

[etrusco]

I'm not an expert in filters nor engines, but if Courtenay and Rouche says the K&N is ok, then that's good enough for me.

I think I'll be ok with the fact you think I'm an idiot for keeping it on

That's all I wanted to know...thanks for being honest
Comforting to know that you are not an engineer or tech. When one fcuks up something obvious and he's an expert in the field people call him an idiot.
When the layman fcuks up, he's just clueless, and can hardly be blamed.
Lazy, I don't think you're an idiot at all, on the contrary, I think you're very brave!
Nothing personal, Lazy, but since I spent lots of dough and free time modyfying cars with moderate results, I'm always interested in learning something new and open to new ideas.
That's why with K&N been there done that.
I sincerely hope your car lasts very long with none a problem!

[R1 nur]

Oh and remember that Vaux / Lotus supplied a "aftermarket" panel filter on the VXR220.

I do not want to get involved in the argument, but Iwould just like to point out that there was an optional (?) recall for the VXR - to swap the panel filter back to the same one as fitted to the VXT.

[etrusco]

R1nur, welcome to this friendly exchange of ideas I am interested by your comment on the panel filter recall, care to elaborate, or if u have more info, links, to go deeper in the issue? Thanks

[cheeky_chops]

virtually every VXR AMM went pop - anything from 100 to 10000 miles

[R1 nur]

I am interested by your comment on the panel filter recall, care to elaborate, or if u have more info, links, to go deeper in the issue?

I had a VXR. Late one friday on my way down the M1 heading for Dover and a weekend jaunt to Germany the AMM blew on my car. The car was driveable but I did not want to take it to Germany.

Anyway I took the car to my dealer in Warwick - and was told the AMM issue was known to Vauxhall and they would be following some directive or other and replacing the filter with the standard paper item.

If I find a link I will post it here.

[R1 nur]

If I find a link I will post it here.

No detail. No help sorry.

LINK

[LazyDonkey]

This failing only affects the turbo and the rubbish AMM though.