"Bryan WIlkinson jr." wrote:

----------  Forwarded Message  ----------

Subject: Re: [Europa Forum]: Mo Gas o No Mo Gas
Date: Mon, 23 Sep 2002 19:37:00 -0700
From: Peter van Schoonhoven <pvans@pacifier.com>
To: forum@europaclub.org.uk

Hi Graham,
Thanks for your comments. Remember that "Lycontinentals" have a
fixed  ignition timing position but it is reasonably well optimized
 for cruise power settings, of say 2500 rpm or so. The difference
 between 700 and 2500 rpm is not so great as the difference between
 idle and cruise on a Rotax.

I agree it would be wonderful to have electronic ignition and fuel
 metering like all modern cars have, but the small volume of
 production will never allow them to amortize the R&D costs, so we
 just keep on like in the 1930's.  These days, Lycoming and
 Continental derive the majority of their business from
 remanufacturing engines, or selling a few new ones to owners who are
 replacing old engines in certificated aircraft. Those have to be
 just like they were, just to meet the regs.

Of course, every now and then a plan hatches for something really new
 and better, like the Porsche engine in the Mooney of the late
 seventies, but history shows us that few pilots will buy them, and
 today, I bet all that were sold have been convereterd to Lycomings.

Best regards,
Peter

Very clearly put , Peter. However I am slightly puzzled by your
reference to tickover. At 2700 rpm I would have thought that two
plugs in a Lyconental were necessary to compensate for the slow
burning plus the effect of the lack of ignition advance with the
magnetos. Apart from the fact that one of the mags will fail
sometime, of course.
Higher EGTs with mags compared to electronic would also confirm
this. A pity the Rotax doesn't have ignition timing  variable with
rpm. IMHO, maybe the would be less wear and tear on the props.
Experience with the electronic systems with proper advance with rpm
seems to confirm this bit of guesswork. Any comment?

Graham

 
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