Question about idle timing
Question about idle timing So I am trying to dial in my cam's idle, and I am reading a how to sticky that says "Make sure that your Idle Spark Advance table (both “In Drive” and “In Park”) match your High and Low Octane Table for all columns up to 1200rpm (HPT > Engine > Spark Control > Spark Advance > Idle Spark Advance (in Park, in Gear), Hi and Lo Octane)." however as you can see from the attached picture, my idle timing and high octane timing are really not close at all. Which table is supposed to match which? Thank you!!
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Joined: Aug 2010
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From: Ann Arbor, MI
You are not as far off as you think.
I checked the Airmass g/cyl at idle on my cam'ed car and it is around 0.21 which is in the red part of your table. Your are unlikely to hit the high g/cyl values at idle speeds, at least not for more than a fraction of a second.
Even the factory stock tune does not have identical values in both tables.
However, I agree that making them agree is a good idea. I would start with the stock Camaro 2002 values (which don't go below 8 degrees advance) and populate the 1200 rpm and under values with those. Populate the Idle-in-Drive, Idle-in-Park, High Octane and Low Octane tables with those values.
If you ever follow the detailed Idle Tuning directions (on the HPT Forum) that may give you better Idle advance values which should then be copied to the High Octane and Low Octane tables.
BTW - My own Idle-In-Drive table looks identical to yours. I'm suggesting the stock 2002 values for its lower conservative values.
Also, I'm not a tuning expert, certainly not like others here.
If you detail more about your car (you have 2 in your sig), the real experts here may be able to give you more accurate advise.
I checked the Airmass g/cyl at idle on my cam'ed car and it is around 0.21 which is in the red part of your table. Your are unlikely to hit the high g/cyl values at idle speeds, at least not for more than a fraction of a second.
Even the factory stock tune does not have identical values in both tables.
However, I agree that making them agree is a good idea. I would start with the stock Camaro 2002 values (which don't go below 8 degrees advance) and populate the 1200 rpm and under values with those. Populate the Idle-in-Drive, Idle-in-Park, High Octane and Low Octane tables with those values.
If you ever follow the detailed Idle Tuning directions (on the HPT Forum) that may give you better Idle advance values which should then be copied to the High Octane and Low Octane tables.
BTW - My own Idle-In-Drive table looks identical to yours. I'm suggesting the stock 2002 values for its lower conservative values.
Also, I'm not a tuning expert, certainly not like others here.
If you detail more about your car (you have 2 in your sig), the real experts here may be able to give you more accurate advise.
