K&N Airfilter - Have one long term, any issues?

I did some acceleration runs with and without a filter. The filter was a new paper one. I did not detect any differences. I changed the filter on the LC when needed and that depended on the state of the tracks etc. Sand and dust were the worst. Paper filters are changed at specific service intervals because Mr and Mrs Joe Blog wouldn't know what they were or were or what they looked like. Suzuki et al need to cater for these people and so they stipulate a filter change even if they may appear to be useable. Better to change it than to have an irate owner demanding a new engine.

Roger

It's entirely possible to use fluid dynamics software to redesign the inlet system of a naturally aspirated vehicle to provide some amount more power than a factory system. What is never going to happen is any detectable increase in power as a result of simply replacing the filtering medium in the standard tract. Unless you add forced induction.

To clarify the situation.
The purpose of the test was not to increase power but to check if a paper element reduced it. My experience indicated that it did not. This serious of tests also proved ( at least to me ) that no air filter would increase power.

Roger

wrote:

It's entirely possible to use fluid dynamics software to redesign the inlet system of a naturally aspirated vehicle to provide some amount more power than a factory system. What is never going to happen is any detectable increase in power as a result of simply replacing the filtering medium in the standard tract. Unless you add forced induction.

Indeed

Dyno tests I've seen would suggest an element swap is in the range of about 0.5hp gain +-

But a redesigned induction setup could yield upto 15-17bhp or maybe slightly more*


*This would depend on the factory setup and type of engine. Larger displacement low tuned engines will often result with good gains. Small displacement more highly tuned engines less so.

Just been reading how this has progressed, interesting to read the yes / no experiences.
What is ROI, Google suggests Return on Investment?


For me the Return on Investment  (if that's what it stands for) will be 3 years from now as I tend not to sell my vehicles and my Jimny is a keeper.  I  have successful use these devices on other vehicles I own, so I only had concerns myself about possible MAF issues.
They obviously aren't for everyone, but when it arrives and gets fitted, the departing paper filter will be the last one I send to landfill which is enough for me.

They are also a bit of a god send on vehicles that ECP/Halfords don't support due to age, not the Jimny (just yet), but the only source for discontinued paper filters can be car shows or expensive club reproduction items.

So looking forward to the increase performance, better mpg

---

.  Only joking, I've got ladders fitted to max out the performance 

​​​​​​