gunmetalgtir said:
Yeah I remember the test, what I meant was if anyone had tried using a different brand of replacement filter then tried testing it again to see if it was any better than the filter that HKS supply? Cause I buy the replacement filters from elsewhere when I need to change it because HKS charge a fortune for them!
All foam based filters are crap. The problem with foam is that you can't make the density small enough to trap dirt particles and flow well at the same time. That's why you see the 'multi layer' filters, like the Pipercross range etc... Adding that particle retention coating just makes things worse as, it get's sucked in too !
So effectively, you get a compromise of poor particle retention and average flow properties. With that in mind, calling an HKS element a 'performance air filter' is an oxymoron !
I had the Apexi unit (GTiR specific) and found, after I changed to a Blitz SUS package that it was quite restrictive.
I did some reading and found that it wasn't down to the construction of the Apexi filter but, it's size. The Blitz is a much larger unit and the theory goes that the larger the surface area the filter has, the smaller the pressure drop across it. So, the better the flow characteristics.
Not that I'd recommend the Blitz SUS kit either as, it's very poor at the filtering part.
I keep meaning to do it and haven't got round to it yet but, I want to replace the Blitz cone with a K&N or preferably Green cone of equal or greater size. They flow very well and also have much better particle retention properties than any other filter on the market.
Basically, it seems that you can't beat the cotton gauze for an air filter material !
Paul