There was a brief discussion of that topic over @ slantsix.com recently, Tim:


http://www.slantsix.com/UBB/Forum16/HTML/006148.html


---Red

I hear you on the supercharger idea but the price of admission is high.

I've got the time and determination to tinker. Two separate sets of runners with butterflies is a neat Idea but then you can only really tune for two different RPM's. A simple tube inside tube runner design with some welding knowhow and an actuator that keys of of vacuum or Tach signal or something could be scrounged for one tenth the cost of a SC.

I'm not going for max HP in the Fury anyhow I want a nice driver with something different under the hood.

No offense meant to the SC Lobby.

_________________
It is easier to REACT,
than it is to THINK!

Middy.

The variable-length runner idea is great, except when it comes to designing it! My buddy's got a 2001 Suzuki GSX-r 1000 (motorcycle, that is); it's a 4cyl inline unit with fuel injection. It's intake is very basic and consists of 4 tubes with 4 throttle shafts. Now, this engine is designed to run from 2000rpm to 12,500 rpm (or so) and makes power throughout the rpm range. The intake has secondary throttle blades, mounted above the primaries, that open slowly throughout the rpm range, being fully open at the upper rpm range. Something like that may work for the six; just design a tube length that would allow max flow at your desired rpm, then figure out what rpm the secondary throttles need to open up at (sounds kinda scary and needs lots o' computer hacking...).

I've also seen a gm 3.1L v-6 (i think) that used a rpm-activated switch that controls a butterfly valve placed inside a split intake plenum. At low rpm, the plenum remained split/separate, and then at a higher rpm the valve opened allowing the engine to access the entire plenum volume. The switch would be easier to work, i think, as any ignition box or even factory computer has the capability to switch on or off at a given rpm...

sounds interesting, keep us posted.