A good history of the Chevrolet Vega:
http://h-body.org/library/vegabob/vega-history-complete.html
"Vega's most unique feature was its 2.3 Liter (140CID) OHC four-cylinder
engine. Unlike previous GM aluminum engines, the Vega block did not have
cylinder liners. GM Research Labs had been working on a sleeveless
aluminum block since the late 50's. The incentive was cost. Getting rid
of those liners on a four-cylinder block would save $8, which was a lot
of money back then. This involved a joint venture between the GM labs,
Reynolds Metal Company, and Sealed Power Corporation. Reynolds came up
with an alloy called A-390, composed of 77 percent aluminum, 17 percent
silicon, 4 percent copper, 1 percent iron, and traces of phosphorus,
zinc, manganese, and titanium. The A-390 alloy was suitable for faster
production diecasting. These qualities made the Vega block less
expensive and easier to manufacture than other aluminum engines! A
process of etching the cylinder block walls exposing the silicone
particles insured a wear surface stronger than steel. Sealed Power
developed special chrome-plated piston rings for this engine that were
"blunted to prevent scuffing. The large bore, long stroke design
provided good torque and lower engine RPM for reduced wear. A cast iron
cylinder head was chosen for low cost and structural integrity, and an
overhead cam was specified. GM decreed, at the 11th hour, every engine
then under development would be required to run on unleaded fuel. This
meant dropping the Vega's proposed compression ratio from 9.5:1 to
8.0:1. This took a bite out of horespower, and made expensive stellite
valves mandatory. 90 HP. L11 option -110 HP...
...Vega Vices, including the least loved powerplant -Early versions of the
2.3 engine were judged rough and noisy. Most however, felt Vega's style
and handling more than made up for it. Although proven reliable, if
engine was allowed to overheat, expansion could cause scuffing of the
cylinder walls, damaging the engine block.
Chevy dealers usually replaced complete engine blocks due to high oil
consumption, assuming block was the cause, when it usually was due to
leaking valve stem seals which beacame brittle with age. This is how
Vega got its "disposable motor" reputation. Chevy dealers didn't help by
not properly diagnosing and servicing it. On '76 engines, Long-life
valve stem seals decreased oil consumption by 50%."
David Riker
davriker@pacbell.net
http://home.pacbell.net/davriker/
http://community.webshots.com/user/fool4mg
----- Original Message -----
From <KrkLH at cs.com>
To: <spridgets@autox.team.net>
Sent: Thursday, November 24, 2005 3:23 PM
Subject: Re: GM going down, no LBC - Now Vega
>I recall the almuminum cylnder bored early designs - what were they
>thinking?
> Has there ever been a successful engine that ran on aluminum cylnder
> bores -
> historically? Did they have something that they could look at that set
> some
> kind of precident for doing such an unconventional thing?
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