Intake resonance supercharging help

Hi guys,

I am not making as much low-end torque as I'd like to, due to minimal back-pressure in the exhaust.

To at least partially counter that effect, I thought of making my intake longer. I already have a home-made K&N conversion, using 3" copper plumbing pipe. I need to know how to figure out what engine speed the supercharging effect from the intake's resonance, given a length and diameter. Does anybody know the math for this?

Going back to a more-restrictive exhaust, or camming/stroking the motor, is not presently an option.

Thanks!

There's a lot to it. What you are looking for is called the Helmholtz resonance. This search gave a lot of good results: http://www.google.com/search?hl=en&lr=&q="helmholtz+resonance"+intake

That, and there's another live post going around about it - http://www.naxja.org/forum/showpost.php?p=553378&postcount=1

I only found that AFTER I posted, of course, cuz I'm too lazy to search first and ask questions later.....

But thanks!