wr250r airbox mod

greetings I run a wr250r 2008 standard exhaust k&n air filter and flapper ect still attached I was thinking of drilling some extra air holes in the top of the air box but I am unsure of how many and what size will work best with standard set up +k&n filter do I need a foam cover over holes ect and will there be a noticeable difference or will I just spoil the air box any advice will be appreciated thanks martin

wr-blaster wrote:

greetings I run a wr250r 2008 standard exhaust k&n air filter and flapper ect still attached I was thinking of drilling some extra air holes in the top of the air box but I am unsure of how many and what size will work best with standard set up +k&n filter do I need a foam cover over holes ect and will there be a noticeable difference or will I just spoil the air box any advice will be appreciated thanks martin

Take a look at your airbox door.  It is really easy to remove it since it is just the screw and a couple of pins with circlips holding those in place.

Just remove the circlips and pull the pins and the door comes right off.  Easiest way to mod the box and very simple to return to stock.  Buddy of mine has been running his 2015 since buying it new like that and swears he gets a performance improvement - I think he just likes the extra induction noise myself.  

I would not be concerned with water entering the box since he and I have crossed many water crossing without an issue.  If you look at the intake to the engine it is actually up near the top of the box and runs uphill.