Formula for Air intake

[zerodegreec]

We are building a air intake for our drag truck. Anyone know of the formula for calculating an air intake?

we found an online calculator but it keeps resetting and is putting the values back to default.

http://www.revtronix.com/techinfo/calculators/airintake.php

Or specs are:
6.3liter
6100rpm
efficency is 150% (turbo charged)

We will be running 80" of tubing to get to our turbo (rear mount)

I would like to have the formula but cant findit anywhere...

[Azumanga Davo]

A good place to ask would be the guys at FastDoorslammers.com, as they are Pro Mod drivers and tech guys who would have the best idea. ;)