Has anyone ever modified there air box the way that Cumminz did in a early post and seem results, I'm thinking about putting in a K&N or similiar filter. I got a 2000 5.9

 

I have the cone type of K&N so I don't thik it would work for me as it also gets air from under the hood.

 

Did you see any results mpg, or power????

 

I can't really say

My Pop ( previous owner ) installed the K&N before I got the truck. he said he swears that he lost abut 1 mpg, but that he felt like the truck had a little more pick up so he left it on. Of course this was back when diesel fuel was a little over a dollar.

 

I'm using an Amsoil cone style filter in place of the stock airbox. When I made the change, I didn't see any change in mpg and no noticable change in power by the extremely accurate seat of the pants dyno. But, I certainly did start hearing the turbo spin up sooner than it did with the stock setup.

Opening up the exhuast recently did more for power (again, no change in mpg) although it could be the combination intake/exhaust that is doing that rather than either one individually.