<E36><M42>advancing ignition questions

[Tony_Estrada@xxxxxxxx]

When manufacturers build cars, they set the ignition timing X degrees past
TDC to allow the car to use gas with a "low" octane rating.
In cars with standard distributors/mechanical ignition I am able to advance
the ignition timing closer to TDC+1 to improve low end power  (but I have
to use high octane gas to avoid pre-detonation - not a problem)

In my 93 318i, the ignition is computer controlled.  Questions:
- - How can I modify the ignition timing?
- - Is the ignition timing that the computer computes the optimum for the gas
type that I am using
- - Does the computer advances the timing until the knock sensor kicks in,
then retards a fraction from there?
- - Is the computer constantly checking for optimum timing advance (like the
vacumm advance in mechanical dist)?
_____________
Tony Estrada
Iris Associates

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