Electro valves

[Carter Shore]

As stated, the acceleration vs valve mass is the
fundamental limitation.

But as an alternative to the simple open/shut solenoid
strategy (as long as we are wishing), why not
servo-valves? 

Servo-valves under ECU control would allow control
over every aspect of the intake and exhaust function.
Control of not just valve timing, rate, and duration,
but lift as well. Implement any camshaft 'grind' by
manipulating valve opening characteristics. No
camshaft, drive, followers, lifters. The throttle
would not be needed. For idle just open valves
minimally to admit enough mixture, for WOT use
whatever gives best VE for that combination of RPM,
temp, load, etc.

Could allow very flexible engine management for
economy by shutting down cylinders not needed
(remember the Caddy V-4-6-8), perhaps rotating the
working power cycles amongst them.

Obvious benefits include power, rev limits, fuel
economy, emissions.

The F1 teams are/were reportedly using very high
pressure nitrogen gas (from an on-board storage tank)
to actuate the valves. This eliminates springs,
keepers, followers, etc.

A servo-valve system could be implemented that uses
solenoids to control the high pressure nitrogen gas. 

Cannot visualize this system for street use. But
perhaps high pressure hydraulic technology could
replace the nitrogen gas for < 8,000 RPM use. You can
get 2,000 PSI hardware anywhere. I tried some trial
calculations to confirm that it was not flatly
impossible, but do not know enough hydraulic theory or
practice to get meaningful results of max
acceleration, rate, sizing, etc.

Just another job for our trusty ECU's to handle. But
how would you implement a 'limp-home' strategy? Lot's
of eggs in one very complicated basket.
 
Thoughts anyone?

Carter

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