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Timing:- Advance RPM, Retard Turbo?

Hi Guys,

Am in the process of studying the ECU workings of the 200T with the 
help of Scott M. Would like to understand the basics behind timing 
advance for RPM and retarding for preventing knocking under turbo 
boost conditions.

PURPOSE: I am in the process of going from a 2 bar "Vacuum Pipe mod" 
to a 1.95 bar ECU system on the MAC13 A (Stock boost +- 1.4 bar)
box we have here.

Q's (Might be really dumb)

1) Is there a formula or a rule that determines the amount of timing 
advance with RPM?
2) What should the initial timing setting be (x BTDC) or does the ECU 
compensate for marginal errors?
3) Where (RPM) should I change timing on my stock code for better 
performance (Assume stock boost level), especially from pull away. 
4) How much do I compensate the timing or calculate the amount of retard 
for increased turbo boost levels?

Any help, any more light on the subject, or a pointer to available 
material on the subject will be much appreciated. 


Renier Meyer
Durban South Africa.
'89 200T , MAC13A ECU, K26, Single knock sensor MC/ MB Motor.
"Occasional smoke and fuel starvation sorted out, like new again"