[s-cars] S6 pinging woes - the continuation

[Taka Mizutani]

A normal combustion event that occurs early is "normal?"

What world do you live in? That is completely illogical.

Now you're nitpicking a very fine point because they're both basically the
same thing, just of a greater magnitude.

Taka


On Tue, Jul 28, 2009 at 2:21 PM, Brett Dikeman <brett.dikeman at gmail.com>wrote:

> On Tue, Jul 28, 2009 at 12:50 PM, Taka Mizutani<t44tqtro at gmail.com> wrote:
> > You've just contradicted yourself, Brett- if the fuel/air charge ignites
> > prematurely, you get a large increase in cylinder pressure, which causes
> all
> > sorts of bad things to happen to the engine.
>
> Again:
>
> PRE ignition is a NORMAL combustion event that occurs EARLY.  Because
> it occurs EARLY, the combustion chamber is under less compression, so
> flame front speed is lower...most likely max pressure and temperature
> are lower than a normal combustion event at full compression.
> Preignition is bad because of how the force generated from combustion
> is applied.
>
> DETONATION is an ABNORMAL combustion event where multiple ignition
> points or spontaneous combustion of the entire fuel-air charge occurs,
> resulting in pressures that are double or more from normal maximums.
> An exaggerated example: compare the difference between a cup of gas on
> the floor of a room burning, and the same cup of gas, vaporized in the
> room for a stochiometric mix.  One sets off the smoke detector.  The
> other blows the room apart.
>
> -B
>