Variable Restrictiveness Exhaust - Meet Mr Helmholz

[Tom Sharpe]

All well states... If you missed it, go thru your trash and read it again!

Robert Harris wrote:

> To review the basics  A Helmholtz resonant intake consists of a largish
> diameter intake pipe, a resonating volume (plenum) and individual cylinder
> runners.  The individual cylinder runners are length/diameter tuned to the
> highest power rpm desired and the helmholz resonator extends the rpm range
> downward.
>
> Reverse it.  Individual cylinder runners, resonating volume ( collector ) and
> a largish tunable pipe.  Size the exhaust cylinder runners for the high rpm
> diameter and length.  Fire them into a collector and then out a pipe.
>
>  or using a vacuum
> headlight actuator to vary the length of a slippy pipe stub coupled to the
> collector.

Robert, I really like the slippy pipes... could you figure out the length from the
sound produced? Sort of a knock sensor approach...

or use lookup tables like fuel, spark, exhaust position??  Just trying to simplify
the process..

Do we need a stepper motor headlight actuator....  Tom S