Yeah, timing is everything, that's why cam lobes/camshafts are on a path
towards eventual extinction and that has already happened in Formula 1
engines with their pneumatically operated valves. Electromagnetically
operated valves have been considered by Renault for F1 use so that
technology is under development and on its way. So eventually all valve
timing/lift-close profiles will be continuously variable and optimized over
the full range of engine operating conditions. Be a long time before it gets
to the Salt, but the rule book controversy could be even more fun than
traction control.
But why not squirt the laser beam thru the valve stem? It's possible to use
a fixed ground based, high power military laser that fires at a space-based,
survivable and maneuverable targeting mirror that reflects and steers the
laser beam towards a moving target with minimal loss of beam energy. It
wouldn't take a very powerful laser beam pulse to ignite the fuel-air
mixture by directing it towards a "mirror" spot on the piston and direct the
beam to a specific spot in the combustion chamber or ricochet the beam
around the combustion chamber if needed. So detonation needn't be a problem,
especially with variable valve timing.
Even if the laser beam is high powered, the pulse duration would be very
short so the total amount of energy deposited on the engine parts would be
low, so maybe very little damage if any---100,000 miles might be a different
story.
It's interesting that top-fuel dragster spark plugs see a power pulse of
about 3 to 4 Megawatts (say 45 amps at 80,000 volts). Continuous 3-4
Megawatts would melt the crap out of anything, but total energy delivered is
tolerable because the ignition pulse is so short. Laser ignition would be no
different.
Lance
----- Original Message -----
From: <wester6935@comcast.net>
To: "Keith Turk" <kturk@adelphia.net>; "DrMayf" <drmayf@teknett.com>; "Bryan
Savage" <b.a.savage@earthlink.net>; "List Land Speed"
<land-speed@autox.team.net>
Sent: Wednesday, February 23, 2005 11:03 AM
Subject: Re: Laser Ignition / cam profiles
> In racing ... like comedy ... timing is everything.
>
> I see this as a potential cam grinders problem. When 50% of your power
comes at what would have to be at least 1 degree after TDC, the problem and
the additional power to be gained is in the remaining burn before the
exhaust valve opens. I can imagine some wild cam lobe profiles..
>
> Wes
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