TMA- timing advance. As long as the ECU sees no knock it will advance timing during the pull. The big drop at 3100 RPM's is normal. The ECU pulls timing as full boost hits then advance. Advance in timing=more power.
Originally posted by turbolarry TMA- timing advance. As long as the ECU sees no knock it will advance timing during the pull. The big drop at 3100 RPM's is normal. The ECU pulls timing as full boost hits then advance. Advance in timing=more power.
Cool, I figured it was something to do with timing... but couldn't figure out what the "M" was for in TMA
Keith
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EVO 11.53 @ 123.37, Black WRX Wagon 13.62 @ 99.24
So you Start with 20 move to 7 then start creeping back up? Is that normal, It doesn't seem efficent... why not just keep it at 20 if it senses knock bring it down a few degrees at a time...
I don't remember my DSM taking so long to get up to 20+ degrees of timing.
Do EVO's have adjustable timing like 1st gen DSM's? I know my datalogging was right around 20-22 degrees with about 13 pounds of boost and it kept right around 19-24 when I ran a 13.6 with that PSI...
When I got it tuned for 20 psi it start right around 23 and came down to about 19.
I know DSM's if they see knock the knock meter wont get reset until you let off throttle 100% then get back on.... is it true for EVO's as well?
So you Start with 20 move to 7 then start creeping back up? Is that normal, It doesn't seem efficent... why not just keep it at 20 if it senses knock bring it down a few degrees at a time...
I don't remember my DSM taking so long to get up to 20+ degrees of timing.
Do EVO's have adjustable timing like 1st gen DSM's? I know my datalogging was right around 20-22 degrees with about 13 pounds of boost and it kept right around 19-24 when I ran a 13.6 with that PSI...
When I got it tuned for 20 psi it start right around 23 and came down to about 19.
I know DSM's if they see knock the knock meter wont get reset until you let off throttle 100% then get back on.... is it true for EVO's as well?
Higher compression, and a higher stock boost pressure = more conservative stock timing curve... perfectly normal. The timing starts high and tapers down as you move towards your peak torque (peak torque = peak cylinder pressure) and after peak torque it ramps back up to give good power.
Keith
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EVO 11.53 @ 123.37, Black WRX Wagon 13.62 @ 99.24
If you mean base timing, no. It's more like a 2g, electronicly controlled.
I don't know what you mean by reset knock meter?
Hey Larry,
I know with the 1G cars (not sure about 2G cars) the ECU learned over time if you had a knock problem and would put in a long term knock correction factor into the timing curve. One of the things Todd Day did with his ECU mods was to make this factor "re-set" to the highest value on every startup instead of keeping a more conservative knock curve if some family memeber put 87 octane in your tank.... it had to re-learn every time, but it also gave you max power on every startup, as long as you were running good gas all the time it was a great modification. As far as the instantanious knock correction on the EVO's, it decays away over a short period of time even if you don't go to zero throttle if I remember correctly. Don't quote me on that though
Keith
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EVO 11.53 @ 123.37, Black WRX Wagon 13.62 @ 99.24
Do you fellas know how I would monitor knock from the ECU?
I am trying to build a custom map and cannot for the life of me find a way to read knock.
Log your ignition timing advance during a WOT third gear pull. As long as the ECU does not detect knock, it will steadily advance the timing. If there's flat spots, or pulled timing, your knocking.
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