When you take the lid off the top of your airbox (4 screws from the top) you'll see what's called a shelf (flat piece of plastic) with 2 large diameter holes in it going downward. The plastic shelf has a couple of tabs that hold it in place in the airbox, if you pry the shelf off you will find 2 cones attached to the bottom of the shelf, this all comes out as one unit. With the shelf and cones removes this is called gutting the airbox. when you now look down the airbox, at the bottom towards the front is where the airbox joins to the throats of the throttle bodies. By removing the shelf and cones there is now less restriction of air to the throttle bodies. From everything I've heard there is not much if any advantage to gutting the airbox on a stock 600, the airbox is adequate to feed the engine all the air it can handle. If you start doing mods like a pipe to make it breath better than there may be some advantage to letting more air in......but remember more air means you need more fuel.......not a cheap endeavor on an EFI sled......not enough fuel means very quick lean out/melt down.......
Ive had mine gutted for many years and never had a problem. the stock programing is so rich the plugs are still darker than id like them to be. the only thing i realy noticed was more noise from the intake
ive got a 99zl 500 efi my box had a sort of baffle if u will i took that out also where the air comes in from the vents above your feet it goes to the box then has to go up and over a wall i cut both those walls out one from each side of box the engine will only suck in as much air as it can so if they are being restrictive then the engine isnt gettin wat it could be getting i hav SLP twins, twin DIY jaws cans, boondocker cntrol box, black magic chip and soon reeds the box will help me alot becuz its gunna breathe better but itll only help u so much
its a cheap and easy mod so y not do it wont hurt anything
that was the very first thing that i did and the cone with the shelf thing is for carbed models the efis have a baffle like thing
Snowpussy...I didn't realize Cat used a resonator box inside the airbox on the smaller sleds.....not cones......but they used it on both the EFI and the carb versions.....the 800 and 900 twins (carbed and EFI) used cones, funnels, or air silencers......whatever term you want to use (Cat actually calls them air silencing funnels)......but they are commonly referred to as cones......
Point is gutting the airbox is simply removing all that stuff. I've seen that airbox mod you're talking about........lots of guys with the big bores use that little trick to get more cold air to the engine........did you put another filter anywhere when you did that mod??
my sled didnt have any filters in it so i did not bother putting any back in nor did i add any anywhere else
(im a little on the cheap side) lol
i am kinda thinkin bout takin the box out and just putting filters on the throttle bodies and mounting a peice of sheet metal to seperate engine area from filter area to act as heat shield/ air flow director so shes not suck warm air
i mite make a complete box that i can still mount the rubber (T.bodies-airbox) on and open up that air vent used by the original box and ill make seperate mounts for the ECU and coil and make a new hole for the air sensor itll take some work but itll give more room for fuel lines and cables and i could move the steering column forward a bit too