Have heard alot of people say the stock filters are not the greatest, would that be a good start and what brand do you recommend? Would I have to rejet it then?

 

I would recommend a k&n, you wouldnt have to rejet it. I would start with an aftermarket pipe.

 

Take $90 of the $200 and get a Pro Flow air filter conversion kit--it's the best mod you can do for a Warrior (in my opinion). In the kit you get a aluminum billet adapter that fits into the slot where the stock filter normally slides into, but has an o-ring that fits between the adapter and box to completely seal out dust when held into place by two screws (you have to drill two holes in the filter box as the screws hold the adapter in place from the outside in). The kit also comes with a foam air filter, but you can always buy a K&N that will fit onto the adapter if that's your preference.

You can also drill 6-8 one inch holes into the airbox cover and install filter vent plugs into the holes for added air flow, keep in mind though that any mod to increase air flow into the engine will lean out the mixture--when I did both I went up two sizes on the main until settling on a 155.

 

After you get the filter kit....IF your son doesnt already have them.....get him a decent pair of riding boots....

 

2000_Warrior_350
Where did you get the plugs for the holes you drilled in the lid?? The Pro-Flow is something i have been thinking about doing, just seemed like alot of money for not that much of a mod, I guess I will have to re-think that one.

 

You can get the plugs from just about any aftermarket vendor. I didn't use the plugs myself--I went with a Poweroll vented lid instead, which has two 1x3" (or so) slots along the right side for added airflow. I like the fact that the lid is clear so you can see the air filter, and the vented lid supposedly passes as much air as a system with no lid.