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**Gregski** · 03-15-2020, 12:45 PM

Idle Tuning - Base Timing

so just to regroup our goal is to keep adding Base Timing in the In Park table under Idle Spark Advance section in the VCM Editor until the Intake Manifold Absolute Pressure (kPa) stops decreasing, whilst keeping an eye on the Engine Coolant Temp, yes this is time consuming and yes you add 2° and have to write the changes to the PCM and then log some data and then add another 2° and log some more data, rinse lather repeat, [really makes you question that mail order PCM tune don't it? ha ha - sorry couldn't resist]

Here you see we bumped the timing from 19° to 21° and saw no change, the kPa was at 38 and stayed at 38, that's ok, let's keep going for a little bit more

Top Tip: we will take baby steps and add in 2° increments though you could bump it to say 25° and see if the pressure drops, if it don't you could save yourself some time knowing you were already at as low as it was gonna git

03-15-2020, 12:45 PM	#368
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,810	Re: HP Tuners Tutorials - Idle Tuning Idle Tuning - Base Timing so just to regroup our goal is to keep adding Base Timing in the In Park table under Idle Spark Advance section in the VCM Editor until the Intake Manifold Absolute Pressure (kPa) stops decreasing, whilst keeping an eye on the Engine Coolant Temp, yes this is time consuming and yes you add 2° and have to write the changes to the PCM and then log some data and then add another 2° and log some more data, rinse lather repeat, [really makes you question that mail order PCM tune don't it? ha ha - sorry couldn't resist] Here you see we bumped the timing from 19° to 21° and saw no change, the kPa was at 38 and stayed at 38, that's ok, let's keep going for a little bit more Top Tip: we will take baby steps and add in 2° increments though you could bump it to say 25° and see if the pressure drops, if it don't you could save yourself some time knowing you were already at as low as it was gonna git Attached Images Last edited by Gregski; 03-15-2020 at 06:41 PM.