Shaun

When I did a lot of testing many moons ago, we found very favourable increases with changing to a K&N panel filter. Tests were re-run back to back (several times) and the results were consistant. +9bhp increase iirc (Spec C with a 3" decat on) over the OE filter. I also tested a large induction kit.... increased the top end power slightly, but lost a bit on spool, charge temps went up and had compressor surge (twin scroll turbo). Same car. Suffice to say we decided to revert back to the K&N filter and that served me well until I went power crazy.