stage 3 air box mods

seems like everyones freaking out about air boxes and intakes and such all the sudden. well my bmc filter took a shit on me so ive been shopping around for the different air filter options and this is what ive come up with:

bullshit kn (minimal filter area results in no increased flow)


shit bmc that is marginally bigger, but will fall apart after a few years


the oem (plenty of area, but restrictive paper media)


and then the newcomer the pipercross
im liking it so far (use of all available area, higher flowing foam media>paper/cotton gauze, and lifetime warranty if it takes a bmc shit on me)

 

Also after taking a verbal beating from norcal boy for years, my therapist has suggested I look into different velocity stack options as to no longer upset him lol. So far, my favorite choice is the 2001-2002 R6 velocity stacks. That generation R6 came with 38mm throttle bodies (2mm larger than ours) so they basically sit flush with our airbox, instead of sliding in and reducing diameter. They are also staggered like ours so you can keep the short front / tall rear set up that the Honda engineers came up with. They are overal a little shorter and wider than ours, which i like, because this means the air filter will not literally sit on top of the stacks (an obvious oversight of the bmc and maybe why the kn is so short). Any ways I wound up trimming a little off the bottom of the R6 stacks, as I had already rounded off the entries to the throttle bodies on the bottom of the air box, so the R6 stacks were actually a little too narrow. I then epoxied them to bottom of the air box in their appropriate locations and sanded it down to ensure that everything was perfectly smooth/flush.

 

so after having driven on this set up for the past week or so, i can say that it feels pretty good. seems like a big midrange improvement, with maybe a little more on the bottom and top aswell. i would like to get it tuned to this set up, and then im sure it would really improve. hopefully ill have the pipercross shortly. and try and get everything really dialled in.

 

we should meet at Gilberts one day, its right under a bridge on the way to the Keys.

I had a 91 and a 93 Nighthawk back in the day. :rip: for both of them. My 93 made 73 hp at the rear wheel...

 

That's actually pretty damn good for a nighthawk. I actually don't live in the keys anymore. I am going to school in Orlando now.

 

No I didn't cut anything out. The BMC just literally fell apart inside my airbox.
But I wasn't judging on the overal area of the filter after its unfolded.
I was judging on the area of the opening of air filter, which is tiny on the kn.

You are right though. The kn has 26 pleats vs. 24 on the BMC.
I don't think that would increase flow at all though.
Maybe filtering capacity though.

 

Not mine but looks awesome, and I would love to have it.

 

That's sharp!

 

I got my piper cross today. Looks of good quality. It was a little hard to fit, but it went in with some finess. A couple of the pros:
It used all available space.
It weighed almost nothing.
It is curved upwards, giving much more space for the velocity stacks than both kn and BMC, which both sit on the velocity stacks.
The cons:
$93
Difficult fit.

 

The red side faces downwards
The black side faces upwards

 

Very nice.

Yeah, noticed the high price as well...

 

It probably wouldn't make much more power than a regular desnorkeled deflappered lid on a stock bike anyways.
but I bet it would help on a more involved build.

 

And why would that be?

 

Temperature of the air charge?

Pulling fresh cool air (higher density) from in front of the engine thru the snorkle versus pulling warmed up air off of the front bank that collects under the fuel tank.

But it looks cool!

 

I read your link, but that was for modern car air boxes with one throttle body and mass air flow sensors. It has absolutely nothing to do with individual throttle bodies and velocity stacks. You do not need an air box with itb. All the tuning is done in the velocity stacks. The air box is there to dampin noise, that's it. I have ridden the bike with no filter and air box cover and it actually felt a little stronger. There was no loss in power anywhere. An air box lid is not going to affect the speed of the air throught the velocity stacks and ports in the cylinder heads. The only way we could lose bottom end torque would be if we inlarged the throttle bodies themselves to a point that they were no longer efficient ,put fairly aggressive cams in the bike, over ported the cylinder heads, ran too large exhaust primaries in the header, or got to carried away with modifications with out compensating for them with a power commander. Think rc45. It comes with 45mm throttle bodies rescricted to 40mm with smaller velocity stacks. Proper airspeed is maintained in the velocity stacks. If you fit larger ones with out race kitting the engine, you will lose power, but if you run an open airbox with the same stacks you will make power.