Air filter induction kits

[Lotusevoraboy]

So I am researching air filters and induction kits at the moment. Quite shocked to see the true extent of black plastic and other restrictive boxery that constitutes the air intake system...based on that of a Toyota Rav 4 some say...with extra boxes to muffle the sound.

I wondered if anyone has either changed the stock filter for a K&N panel filter and seen any difference in noise, bhp, smoothness etc.

or..

Whether anyone has seen or used the Radium induction kit which says it adds up to 21 bhp and sounds fantastic...costs $430...about £280. Looks a quality product, has anyone had experience of ordering them from the USA, or using one?

[LogicSnap]

set aside about 2hrs and look at the "other" Lotusforum dot com, tons on there about CAI (cold Air Induction)kits inc. TDI (company based in Essex) dyno reports etc etc lots to learn on that one!