How do you tune an ECU without knock control

[Bruce]

Snippage for preservation of BW:

> I didn't say some was to be tolerated.

> I specifically stated condition under which light knock was
> acceptable; i.e. when it's not severe enough to strip the protective
> boundary layer from the surfaces. One also doesn't advance the
> timing until light knock is encountered; timing is advanced until
> the maximum torque is available at the crank; the advance is limited
> by the onset of knock - if that should occur.

Quick lets get a dicitionary and play games over acceptable, and tolerated.
In the above statement you revert back to ignoring bearing damage.

> The future may see
> indirect pressure measurement being used in production cars; e.g.
> piezo washers under head bolts. These allow the magnitude of
> the pressures to be determined (ref SAE 1999-01-054).

Thought that was in use already.

> Alternative technologies such as ion-current sensing are still being
> refined (Bosch: SAE 1999-01-0204) to improve knock detection by that
> method. Ion-current detection requires a "static" ignition system,
> with a coil per spark plug and favours a non-central plug location.

If you limit yourself to Bosch's logic.

> The Bosch paper also describes some criteria for knock sensing and
> nominal boundaries for pressure and knock-index.
> It should be noted however that pressure is not in itself an
> indicator of the likelihood of damage due to knock. It's the gas
> velocity that does the damage; stripping the boundary layer and
> exposing the surface of the metal to excessive temperatures.
> The magnitude of the higher-mode oscillations in-cylinder is
> therefore more significant than the primary mode due to knock.

Guess you've never seen an engine *lift* a head.

> One can exploit the knowledge of the manufacturers in acoustic
> detection (even if this is a DIY list :-)) and look at the
> _conservative_ knock bounds (in terms of magnitude at particular
> speeds and loads) as used in production engines upon which your
> beast is based.
> The bounds have to be conservative, especially on German cars
> because these can be used continuously at maximum power, possibly
> for hours on end on public roads. It's expensive to replace engines
> under warranty.

Max power for hours on end?.   So in Germany the cars are sold without any
speed limiters?.  Roads are that barren?.   That statement sure seems to
follow form with some others you've made.
Bruce

> Bernd Felsche

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