Gasoline octane ratings indicate the temperature at which the gasoline
will self ignite - that's without a spark plug. The HIGHER that
temperature is the higher the engine's compression ratio can be without
preigniting the fuel, a/k/a "pinging".
Preignition occurs before the piston reaches the very top of its stroke
so the too early explosion is against the still rising piston i.e. the
engine is working against itself. On hot summer days you may
occasionally hear a bit of pinging, even with 92 octane due to the
engine's somewhat higher than normal temperature. In the winter you may
get by with medium grade fuel.
On Thu, 17 Jul 2003 04:03:44 GMT, "Chris O'Malley"
Here a bunch of URLs to read for you:
One way is:
There is a link called "Groups" where you can search archives of all
groups. If you just want to search alt.auto.mercedes, specify that
group at Google. Or use the following URL:
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