I got mine at the Yamaha dealership where I purchased my Raptor. Like I said, I have the extended warranty, so I had them install it and re-jet so as not to affect my warranty. The UMI box cost $199.00. That is expensive, but worth it in my opinion. You can find aluminum air box's for cheaper if you order them from advertisements in Dirt Wheels mag, but they are all around $180.00 to $200.00. You may be able to get it with an air filter for close to that price. This will be the cheapest way to go if you don't mind and are willing to do the work yourself. To install the new air box, you must remove the rear fenders and possibly the front and gas tank. I'm not for sure about the front though. It is expensive, but makes a big difference in power and most importantly, protecting your expensive engine. I planed on keeping the stock air box, but after cleaning my filter for the third time, I noticed that the foam seal around the air filter cage was starting to come loose. This is a sure way to suck dirt into the engine. With the new air box, this problem is eliminated, as you will use a Pro Design filter, which clamps securely to the aluminum air box. The cheaper way to go is with the stock air box, and a Pro Design filter and adapter, but looking at Dyno graphs of Raptors running with this set-up, you will see that the graph is very jagged, indicating turbulence in the air box. With the larger aluminum air box, this turbulence is eliminated, and the Dyno graph is very smooth. I have also heard of people on this forum complain about not being able to get their Raptor jetted properly with the stock air box and no lid. With my UMI aluminum air box, they got my jetting perfect the first time. The throttle response is awesome and crisp. Who knows you may be able to get the same performance with the stock air box and no lid, but I like my aluminum air box [img]i/expressions/face-icon-small-happy.gif[/img]

 

I think I have narrowed it down to the CFM box or the Graydon. It looks like I can get the CFM box on ebay for $200 with the K&N and another $20 for the outerwear over the box. The cheapest I have found the Graydon is $199 for box, $50 for K&N, and $15 for outerwear.