Air box versus K & N air filter

[Rickracer]

Yes, it will lean the motor out a bit,

 

[CoyCaller]

What do you know, Rick was right. I pulled the stock muffler off and ran the engine without it. It runs awesome. I cut the muffler off and welded on a pipe and we are in business.

THANKS RICK!!!

Sorry about the hijacking of the thread.

 

[anderkart]

Now you'll probably wanna take some new plug readings to see if your jetted right.

 

[CoyCaller]

As long as it runs for the kids it will be fine. If it was my dirt oval racing kart I would probably do that.

 

[Kenny_McCormic]

I've used both K&N and Uni (each corectly cleaned and oiled) on a very dusty dirt oval kart track and found equal amounts of dirt residue stuck to my carbs bore that had obviously passed right through each of these filter brands.

If your serious about making either one of these filters work way better I'd suggest using a prefilter (or outerwear) sock that fits over the filter: http://www.outerwearsracing.com/ They truly help both of these filter brands to work way better.

Was it a dual layer uni?

 

[anderkart]

Mine's the black Uni with a removable red outer layer only covering the sides.

 

[NJOHC]

I see someone earlier in this thread mentioned drilling holes in the airbox. Hopefully you are not doing this between the filter and the carb because the results will not be good. Dirt and engines do not mix well.

I meant on the cover so more air got to the filter. Not below the filter on its way down to the carb. lol If I did that where we ride Id be lucky if it lasted 30 mins! haha

 

[CoyCaller]

I was hoping that is what you meant. lol

 

[brendonv]

I meant on the cover so more air got to the filter. Not below the filter on its way down to the carb. lol If I did that where we ride Id be lucky if it lasted 30 mins! haha

Ive tried this before and it does nothing. Those stock filters can only suck in so much air. Drilling more holes doesnt do anything. The people at honda and the like are not silly. They put in enough holes so it gets the most amount of air flow it can for that filter. Maybe if u run ungoverned it may help a tiny tiny bit in the higher rpm range but not noticeable unless u dyno it.