exhaust system idea

[Clarence L.Snyder]

> Wasn't the original question about the concept of a variable back pressure
> exhaust system?  I think the idea is great, low to mid rpm gets more
> backpressure, then as rpm's increase, backpressure decreases to none.
> That's where the open pipe idea came from.
> 
> If this idea were coupled with a variable valve timing setup, it would allow
> the best performance through all rpm ranges.  Of course, it's all shooting
> from the hip theories!
Kinda like the RAVE valve on a SkiDoo 2 stroke