20 Mar
2001
20 Mar
'01
11:10 a.m.
Mike Ford wrote:
[snip]
Highway mpg hasn't changed much,
because getting a correct mixture at a constant cruise speed isn't nearly
as hard of a job and carbs did just fine. The achievement is to get low
emissions and good mpg during short trips around town, while the engine is
still cold etc.
It's clearly the case that modern engine management does wonders for
emissions,
as well as for reliability -- the forest of vacuum lines, delay valves and
motors has, in most modern engines, simply vanished. That said, a
sophisticated
engine management system clearly _can_ make a difference when it comes to
highway
mpg, because when steady state is achieved for even a short period of time
the
system can lean the hell out of the mixture. This, in fact, rather than
emissions,
was the reason the Porsche finally went to liquid cooling; the Motronic
system
could happily lean the mixture to the point where the cylinder head
temperatures
became untenable...
Chris
Who ripped out the injection and is running 50MM PMOs on his -- and
(currently) hating it...
--
Chris Kennedy
chris(a)mainecoon.com
http://www.mainecoon.com
PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97