NYT article - GM cylinder dropping

[Marteney, Steven J.]

Hope it's a bit more sophisticated than that.  Shortening the lifters means
both valves are closed (non-OHC engine) which equals massive pumping losses.
(Try pulling one plug wire and then go check your mileage.)  Seems like they
meant to say it "telescopes" the intake lifter but expands the exhaust
lifter so the exhaust valve stays open all the time.  Don't think you'd want
to leave BOTH valves open all the time.  Although, may create an interesting
EGR effect.  :-)

Steve

-----Original Message-----
From: Bob Valentine [mailto:bob at tecmark.com]
Sent: Wednesday, May 30, 2001 3:30 AM
To: gmecm at diy-efi.org
Subject: NYT article - GM cylinder dropping


Not exactly EFI related, but GM related.

New York Times, Business section, 5/29/01 article says GM is in concept
with a new version of the 1981 "4-6-8" motor in trucks which alternates
between 8 and 4, no 6 due to vibrational problems.    Says a 8 to 10%
increaes in fuel efficiency.

"In the new version, an electronically controlled hydraulic system, which
uses ordinary engine oil, is used to alter the lifters...   The lifters
shorten themselves by telescoping, thus closing off the valves".  

-> Bob Valentine
-> bob at tecmark.com
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