Improvements to stock airbox?

[bbutler455]

I am keeping my 82 Katana stock in appearance (with the exception of the Yoshi exhaust. I have a KN stock filter replacement. What improvements to the stock air-box should I make? The carbs are getting dyno-jets.

[salty_monk]

You might be able to remove the lid or drill some strategic holes in it... but it will probably just make it hard to tune.

K&N Inbox & Dynojet kit works fine in my experience.

Dan

[sharpy]

You could bolt a huge K&N filter to the back of the carb intake box. You just have to weld some hooks onto ure battery box and use rubbber bands (tube cut offs work) to hold the battery down. But on a kat the air box sticks out a little near the brake reseviour.

[Nessism]

Common hot rod trick from back in the day was to remove the airbox lid. This mod kept the low speed flow pretty similar to stock but flowed better at high rpm. Because of the way the airbox flowed you can get away with keeping most of the stock jetting except for the mains - 122.5's with the rest of the jetting stock when running a street header.

[bbutler455]

You might be able to remove the lid or drill some strategic holes in it... but it will probably just make it hard to tune.

K&N Inbox & Dynojet kit works fine in my experience.

Dan

What is a K&N Inbox? pod filters?

[spyug]

Interesting thread.

On my Kat project I am missing the filter box to the airbox. I also have airbox hoses that have hardened so I'm doing some customising.

So far I picked up a small donut shaped Fram filter and built an adapter to place it where the stock box would be.

As the tubes from the airbox to carbs are on back order and cost $19 apiece I decided to try and make something myself. Today I found a rubber hose that will fit the box and the mouths of the carbs. Tonight I'm going to try and fab them up.

I'll post some pics when I can.

Good luck with it.

Cheers,
Spyug

[boingk]

Modifications to the stock airbox have pretty much been covered, apart from perhaps adding some reverse taper inlets. The theory behind these is that the narrow tip collecting the air, coupled with the larger end entering the airbox, has the effect of smoothing the turbulent airflow and creating denser air in the airbox. The net effect is potentially higher horsepower due to more even carburation, caused by denser air with less turbulence.

So yeah. Whack some reverse tapers on that sucker.

- boingk

[bbutler455]

Modifications to the stock airbox have pretty much been covered, apart from perhaps adding some reverse taper inlets. The theory behind these is that the narrow tip collecting the air, coupled with the larger end entering the airbox, has the effect of smoothing the turbulent airflow and creating denser air in the airbox. The net effect is potentially higher horsepower due to more even carburation, caused by denser air with less turbulence.

So yeah. Whack some reverse tapers on that sucker.

- boingk

Wouldn't you want the small end of the cone towards the carb?

[piester]

If the smaller end was toward the carbs it would create more turbulance. Facing them away disperses the air more evenly at a slower pace. Less turbulance and it will also prevent cross winds from affecting the way the bike runs. Or is it effecting