Custom airbox question

[lshobie]

Hi Guys, I just about have my sled done, I have no airbox so I have to make one which is no big deal, but I was wondering if it is possible to juts not use an airbox, run a pipe off the carb to a K and N air filter with a snow sock on it???? I can run it so it is cold air intake.

So, airbox, with filter or no airbox and just a pipe with filter?

Thanks!

[Mule]

:nod

that's what I did with mine.

/Polaris/DIY Air Intakes

[lshobie]

That's what I figured, good work!

Thanks.

[LRD]

The thing to keep in mind is the carb tuning will likely change without an air box.
Usually goes leaner. Guessing a lot of guys who think they are getting more HP without an box is because it just went 2 sizes leaner on the main jet at full throttle full RPM. Here's a link to a article that will give a clue about the complexities of tuning an air box. They can give free HP when figured out.
http://www.saltmine.org.uk/randy/airboxdesign.html

SnowTech mag used to have a real good read on airbox tuning but appears they took it down.

Good Luck

PS The first piece of Carbon Fiber I made was an air box for A 617 Rotax I put in my Phazer in the mid 90's with TMX Flatslides.

[lshobie]

Very good points, when I picked up the engine from JAWS after porting and polishing he had asked me if I was going to use an airbox - he said with the porting and without airbox I should be going up 6 jet sizes and work from there so I'll follow that advice for now as a starting point. The engine is out of a VK so they run pretty rich to begin with which is why I suspect they put 30,000 kms on them before rebuild in some cases.

[FORDpickupman]

That is a fascinating article.......

I've been thinking about building an airbox for one of my sleds that has a different engine swapped into it. Its not as simple as I thought......