| The subject of air filters has been covered many times on here so here`s my bit.
having run my 998s with standard filters for some time i then fitted the original JHP undertank "sausage" type filter, results were a better throttle response ans engine pick up.
I then changed to the very large K & N style undertank filters. the result was masive in terme of response & pick up but now I have the occasional spit back or stall after a high speed run????
I shall now fit a power commander and have it set up on a dyne, probably Ryno Dyno in croydon in the early part of next year.
Hereare the two JHP filters I hva used | 
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