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Author Topic: Air Box  (Read 1178 times)


  • Bob's Your Uncle
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Re: Air Box
« Reply #15 on: July 12, 2011, 06:13:43 pm »
Ya thats 'em. Makes sense. I always wondered why people trusted those things, I guess they are ok with a bit of wear!

[ok since I've officially put this off topic..]
I thought about creating a positive pressure situation on my air box by wrapping a 1/2 circle around the back of the filter and then I was thinking that the air would sort of be forced into the back of the filter. I'm probably not describing this well...

So like in this pic, on the back side, put some sort of cover that would direct more air into the filter. It could attach to the two metal sides and have a snorkel/venturi-type doohicky on the top and bottom to catch and force air into the element as I rode.

I just whipped this up in photoshop..

Would it work?
« Last Edit: July 12, 2011, 06:32:37 pm by Sub »


  • Grand Gearhead
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Re: Air Box
« Reply #16 on: July 12, 2011, 06:33:37 pm »
Your idea might work and it might not.

An old engineering slogan says, "Common sense does not make for good engineering."

Air doesn't always behave like common sense would think it would.
Increasing velocity for instance reduces pressure so directing some fast moving air past the outside of the filter could actually reduce its ability to suck fresh air into it.

Without knowing exactly how much air was being sucked thru the filter you really don't know how large the accumulator would have to be to keep it from restricting the airflow at the rear.

It basically boils down to things that look like they would improve things (like airflow) often have the opposite effect.  That's why big companies spend millions on testing ideas before they are used or rejected.

« Last Edit: July 12, 2011, 06:36:06 pm by Arizoni »
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Ducati Scotty

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Re: Air Box
« Reply #17 on: July 12, 2011, 07:07:41 pm »
+1.  Just leave it ;)


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Re: Air Box
« Reply #18 on: July 13, 2011, 02:57:21 pm »
As Arizoni sez, You can't for more air though the filter. The best place for a filter to be is in a big box that supplies the volume of air that the filter and engine require without forcing the issue. If you try to force more in,as Arizoni sez, it just dams the flow. I'm not sure if the Enfield is the best setup as it comes, but without a flow meter and other measuring devices, dynos, etc, you'll never know.
I've seen one setup that used a K&N that is longer than the one you're showing on a much straighter tube running into the injector. It looks like a better setup,  but I haven't seen dyno run data on it yet.   
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