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turbo_bu
May 17th, 2007, 03:14 AM
I am trying to get a better understanding of where the actual location of pilot injection is. If you log the main timing and pilot timing they do not add up to the same as the main timing table value and pilot timing table value that are in the EFI Live tune. If you calculate the duration of the pilot injection in crank angle degrees, then the pilot timing (PINJTIM) in your log is equal to the main timing (MNINJTIM) + pilot injection duration. So, can you really run a pilot into the main if the pilot timing value is something bigger than 0?

lakingslayer
May 21st, 2007, 09:18 AM
The pilot table is based on how many degrees before the main shot starts. If you have a main shot at 5 deg and a the pilot table has a 10deg timing then the pilot time will start 15deg BTDC. I'll have to look at some of my logs and see what the pilot is doing. I haven't played with it much yet.

turbo_bu
May 22nd, 2007, 03:12 AM
That is what I thought too, but from looking at the logs from EFI, it shows a higher number than say 15 deg BTDC. From my quick look, the log actually shows the pilot starting before that. The only thing I could think of is that either the log value is wrong, or the pilot timing table is actually the end of pilot injection.

lakingslayer
May 24th, 2007, 02:55 PM
Maybe the EFILive guru's can shed some light on this.
My main injection timing is 3.2 in my tune and the scan tool says 3.0deg. This is correct. My main injection after pilot D is 11.8 but the scan tool reports the pilot timing to be 18deg.

What is causing the descrepency here?

turbo_bu
May 25th, 2007, 03:06 AM
A quick check would be to find out what is the duration of the pilot injection. To do that, find out how much pilot injection you are putting and what is the associated duration in milliseconds. Now take the engine speed (RPM) and mulitply by 360 and divide by 60 ... that will put it in degrees / sec. Now multiply that by the duration (milliseconds) to get the duration in crankshaft degrees. From the condition which you reported, it should be ~ 3 degrees.

Not sure if the EFI live guys have dug into this or know if there is simply some descriptions which are being misunderstood, but I would like to know for sure before I start moving the pilot around too much.

GMPX
May 30th, 2007, 07:48 PM
Bump as a reminder to myself to look into it.....

sweetdiesel
July 21st, 2007, 04:00 AM
this might help

Pilot timing(PIINJTIM)= inj timing C + after inj timing D +(pilot pulse*rpm*3/500000)

Intel
January 19th, 2008, 05:15 AM
Bump as a reminder to myself to look into it.....

Does anyone know if this issue was resolved?

Intel
January 25th, 2008, 08:31 AM
Any thing?

abkimble
January 25th, 2008, 06:25 PM
Pilot timing depends on mm3 injected. If quantity is lower, Pilot " D " will be referenced for actual mm3. Injector on off should be considered as well.

Intel
January 28th, 2008, 03:19 AM
Which PID is actual mm3?