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**Gregski** · 02-28-2020, 09:35 AM

Timing - Burst Knock Retard

Burst Knock Retard (pronounced: Predictive or Preventive Knock Retard) is a means of pulling timing out before a knock even happens based on an abrupt throttle change resulting in a sudden drop in cylinder airmass.

the Burst Knock settings are found under

Engine \ Spark \ Retard tab \ Burst Knock Retard section

How big of a cylinder airmass change needs to happen before the PCM can take preventive action is defined in the Enable Delta Cyl Air table (delta meaning change or difference) if you were to upgrade to a bigger cam, you most likely would increase the numbers in this table to make it more tolerant and less reactive ie less sensitive.

So for example once the PCM sees a 0.020 grams change at say 2,000 RPM it will consult the vs. RPM table to find out how much timing to pull out, and from what we can see at 2,000 RPM it will pull out 6 degrees of timing.

So that's how that works. For beginners and stock(ish) engines we leave these tables alone. If you pinky promise to only put high octane 91+ in your tank and want to add a bit of gitty up into your truck engine you can experiment with increasing the numbers in the first table Enable Delta Cyl Air in the lower RPM range say 1200 RPM and under.

02-28-2020, 09:35 AM	#303
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,810	Re: HP Tuners Tutorials - Timing Timing - Burst Knock Retard Burst Knock Retard (pronounced: Predictive or Preventive Knock Retard) is a means of pulling timing out before a knock even happens based on an abrupt throttle change resulting in a sudden drop in cylinder airmass. the Burst Knock settings are found under Engine \ Spark \ Retard tab \ Burst Knock Retard section How big of a cylinder airmass change needs to happen before the PCM can take preventive action is defined in the Enable Delta Cyl Air table (delta meaning change or difference) if you were to upgrade to a bigger cam, you most likely would increase the numbers in this table to make it more tolerant and less reactive ie less sensitive. So for example once the PCM sees a 0.020 grams change at say 2,000 RPM it will consult the vs. RPM table to find out how much timing to pull out, and from what we can see at 2,000 RPM it will pull out 6 degrees of timing. So that's how that works. For beginners and stock(ish) engines we leave these tables alone. If you pinky promise to only put high octane 91+ in your tank and want to add a bit of gitty up into your truck engine you can experiment with increasing the numbers in the first table Enable Delta Cyl Air in the lower RPM range say 1200 RPM and under. Attached Images Last edited by Gregski; 02-28-2020 at 09:51 AM.