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**Gregski** · 02-22-2020, 01:39 PM

Timing

Example: Let's assume at 2,200 RPM the PCM calculates the Cylinder Airmass as 0.44 grams, according to this table that calls for 29* of timing advance. However the MAF and or the VE Table were not calibrated and are off, so the actual Cylinder Airmass should be 0.48 grams, now the correct timing should be 26* degrees. That's three degrees off, it could mean the difference between a smooth running engine or engine knock occurring. In higher RPM ranges under higher load, such a discrepancy can easily rob you of some power, and this was only a difference of one cell, imaging being two or three cells off.

02-22-2020, 01:39 PM	#284
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,810	Re: HP Tuners Tutorials - Timing Timing Example: Let's assume at 2,200 RPM the PCM calculates the Cylinder Airmass as 0.44 grams, according to this table that calls for 29* of timing advance. However the MAF and or the VE Table were not calibrated and are off, so the actual Cylinder Airmass should be 0.48 grams, now the correct timing should be 26* degrees. That's three degrees off, it could mean the difference between a smooth running engine or engine knock occurring. In higher RPM ranges under higher load, such a discrepancy can easily rob you of some power, and this was only a difference of one cell, imaging being two or three cells off. Attached Images Last edited by Gregski; 02-24-2020 at 05:17 PM.