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A question of timing?

Posted: January 11th, 2012, 6:28 am
by skiptownmcat
I have been slowly advancing ignition timing in the base table and am now getting close to some of the max values, should I adjust the max values as well? Perhaps 3-6k, 1.6 load upwards? or just across the whole table?
Am I right in thinking that it starts at the base value and increases to the max value as you accelerate?

Re: A question of timing?

Posted: January 11th, 2012, 8:12 am
by Rich990
from what i read elsewhere on here it starts at the base and increases to the max value, if/when if picks up knock it then pulls back.

I could be/ am probably wrong.

Re: A question of timing?

Posted: January 11th, 2012, 10:50 am
by Steve @ VersaTune
As far as I can tell from looking at the code, it increases towards max timing under steady state operation. Under acceleration, it will likely only use the base table. Be careful tuning timing aggressively during cold weather. When things heat up, it may start knocking. You may want to increase the high BAT/ECT timing retard to compensate.

Re: A question of timing?

Posted: January 11th, 2012, 12:19 pm
by skiptownmcat
11c ambient temps today, will probably be around the same till April. It's also around half way between summer and winter temps so should not be too bad when things heat up.
I might just increase the last 3 lines in the max table half a degree and the 2+ line by a full one and see how that goes.

Re: A question of timing?

Posted: January 13th, 2012, 4:25 pm
by skiptownmcat
Steve @ VersaTune wrote:As far as I can tell from looking at the code, it increases towards max timing under steady state operation. Under acceleration, it will likely only use the base table. Be careful tuning timing aggressively during cold weather. When things heat up, it may start knocking. You may want to increase the high BAT/ECT timing retard to compensate.
What if the base values exceed the max values?

Re: A question of timing?

Posted: January 13th, 2012, 4:33 pm
by Steve @ VersaTune
I believe it starts high and goes down towards the "Max" value.

The Max name may be a bit of a misnomer in this scenario.

Re: A question of timing?

Posted: January 13th, 2012, 4:46 pm
by skiptownmcat
It does at the lower loads, but at the higher loads max is more than base.

Re: A question of timing?

Posted: January 13th, 2012, 5:16 pm
by Steve @ VersaTune
Right. I was referring to the scenario you described above.

Re: A question of timing?

Posted: January 13th, 2012, 5:33 pm
by skiptownmcat
Hmm, so if there's no knock with the base I could put the max value the same?

Re: A question of timing?

Posted: January 13th, 2012, 5:35 pm
by Steve @ VersaTune
Do you not want it to increase under steady state operation when no knock is present?