Modded/Stock air-box vs Hi-Flow air filter.

[scootnewb]

After reading a comment from another member, I plan on putting the air box back on and modding it instead of using the uni-flow to see if it performs better.  

I figure many of you have already run tests and could give some feedback.

Please discuss

Thanks

[Rune 75]

Performance is the same but less noise with stock air-box.

[V90Performance]

I find it easier to tune with the stock air box.

[scootnewb]

Thanks everyone. It looks like I will go with the airbox.

[cagiva4ever]

this job requires determination. the Stock AirBox needs fine tuning Via:

-Air intake hole adjuster.
-inside airbox is a short tube/pipe. it exist at least in 2 diff lenghts. Via its lenght and Velocity flow optimicing shape, the AirMass amount and velocity is adjusted/tuned. Stock tube is symmetrical in shape, varies only by lenght. by DIY making a replacement pipe that is lenght and shape formed, Velocity is increased-> more Torg more speed, better throttle response.....
- stock foam panel can be replaced with a Aftermarket foam panel "cut into size" , thickness and flow rate can be chosen.

-4th modd is to verify that AirBox has Moisture drain hole at rearend bottom. if no hole, then it needs to be made.


"Hi-Flow" open air filers do not have any of above functions. no Helmolz resonance, no stability, no pre-filling of airmass. no variable velocity.
"Hi-Flow" filters they only have Turbulence in a negative meaning...



it aint job for lazy people, best settings wont be found on 1st try. do it half ars* and its FAIL.


Also, on some 139QMB CVK's the spring over throttle slide is too stiff, at least it was on early 2000 until 2005 era, PD18J models. things havent changed much since on Present time... During back then, Trick was to Shorthen the spring by ~2 coils/rounds. it then let the Slide open more Linear, less Jerking......