I have a 03 raptor. All I have done so far is put on an wb e-series, dyno jet kit and pro flow filter kit. I run it with no lid. I runs great, there are no misses or hesitation. What kind of gains would I see from a 10.75 piston and a stage 1 hot cam? And would I have to change the stock head pipe?

 

The gains in performance are considerable with the Stage 1 and 10.75:1 piston. I don't think you'll have to change your headpipe. Hope this helps you out a little!!!! XR

 

I am running a yoshi slip on , jet kit, kand n, and also hace the cam and 10.75 piston. I am running it with my lid on. I can't say I noticed a dramatic increase in horse power but it does seem to rev better and does feel like it has a few more horses. Would I do it again yes. I have three budies with similar mods who do not have the cam and piston and I am always to the top first. Hope this helps

 

More than what you saw from the pipe/filter/jet kit.

Mugsy take the lid off and you should pick up a couple more ponies and a couple bike lengths more over your friends.

 

I just worry about getting sand in my air box. Do you guys who run with your lid off have this problem. I just don't know if it is worth the risk. Maybe I will buy the screen filters that go over the holes if I drll holes in the lid of my air box

 

Yes, Sand gets in the box. I use a K&N pro design filter with flange and an outerwear over the filter. They do make outer wear covers for the box also. I've never had anything get past the K&N filter. Nada. I've never seen a foriegn object inside the boots of my quad.

 

After riding a day and a half at Glamis almost nonstop I had very little sand in my filter and airbox. The area is well protected even without the lid on.

 

I just ran my quad last week at dumont, and had a stock filter in with: 11:1 wiesco piston (670cc), stage 2 web cam, dyno jet kit, big gun exhaust. i just got a pro flow put on last nite, and am wondering how much improvement i will get

 

Did you go up on your jets?

 

185:180, i used to be 180/175 before filter, i was talking about the specs before i changed out the filters