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Ignition tables contain the base ignition timing for low and high speed cams. Note that additional compensations are applied to the base ignition timing and the final ignition timing may be different from the base table values.
EGR Ignition Tables
The indices are RPM and EGR(%). This table affects partial throttle ignition timing when EGR is between 12 and 25 percent. At full throttle, when EGR is between 0 and 3 percent, changes made in the first two columns have little effect. For full throttle ignition changes alter the Knock Ignition Limit tables.
Individual cylinder ignition trim
Individual cylinder ignition trim adjusts the ignition timing for each cylinder. This table should only be adjusted if an exhaust gas temperature gauge is used to determine the correct ignition timing for each cylinder.
Air temperature compensation
This compensates the ignition timing by air temperature. Two tables are used - for low and medium to high load. The cross-over point between the tables is approximately 40 kPa manifold pressure. Positive values in the tables retard ignition; negative values advance ignition.
The ECU normally applies any IAT based ignition retard to the knock ignition limit tables. This means that any IAT ignition retard only reduces ignition timing when the knock ignition limit is close to the MBT ignition timing. If you want to apply the IAT retard to ignition advance regardless of the knock ignition limit, then uncheck the 'Ignition IAT retard applied to ignition knock limit' option and check the 'Ignition IAT retard applied to ignition advance' option. Note that only one of these options should be checked a time.
Coolant temperature compensation
This table retards the ignition when the coolant temperature is below normal operating temperatures. Two tables are used - one for low load (below approx 40 kPa manifold pressure), and one for high load. Positive values in the tables retard ignition; negative values advance ignition.
This table retards the ignition when the coolant temperature is higher than normal (overheating). Two tables are used - one for low load (below approx 40 kPa manifold pressure), and one for high load. Positive values in the tables retard ignition; negative values advance ignition.
When cold the ECU retards the ignition to increase the catalytic converter temperature. For race vehicles without a catalytic converter this may be disabled.
Throttle tip in retard
These tables determines the amount of ignition retard upon throttle tip in.
Ignition retard rpm compensation
Sets the amount of ignition retard by engine speed. A higher value is more ignition retard.
Ignition retard throttle compensation
Sets the amount of ignition retard by throttle position. A higher value is more ignition retard.
Ignition retard gear compensation
Sets the amount of ignition retard by gear. A lower value is less retard, a higher value is more ignition retard.
This table allows the ignition timing to be altered by gear. Positive values will advance, negative values will retard. Note that the ignition timing is change for all load and rpm values in each gear.
For gear compensation to be applied, if available, select 'Ignition IAT retard applied to ignition advance' from the 'Ignition' -> 'Air temperature compensation' section.
This table sets the base ignition when cranking the engine by coolant temperature.