Today i modified the air filter housing on my 2004 ka and what a difference it's made, No drilling was involved and looks standard from outside. K&N panel filter next. Not bad for 10 mins work.

What was the modification then?

Done some detailing and a bit more modifying today, Getting a k&n panel filter next week to finish it off.

Sorry for the delay in replying, Only attempt this if you are competent with a hack saw and have a replacement air box. ( i accept no liability ). First remove the air box from the car and then remove the resonator from the top of the air box ( it just pulls off). Cover the hole that's left with fibre glass or duck tape ( or just leave as it is....Just makes more induction noise ). Now un-clip the two sections of the air box, you want the section with the flute like bit in it. Now cut the flute like at the wider bit just before it narrows, only cut it to half way through and separate the top from the bottom bit. You leave the bottom bit in place as that's the bit that holds the cool air duct in place............That's it job done! Just add K&N panel filter if you wish.