Injection Timing / Pilot

Trying to understand how all things go together. Here is something I don't fully understand:
Is the Injection timing (B0908-B0910) the timing of the Pilot Injection? Injection Timing After Pilot (B0926-B0929) defines the main fuel pulse. Does it start when Pilot Injection is over?
What happens if there is no Pilot (B0748=0 -> B0721)? Is there any relationship between the Inj. Pulse and the Timing?

Thanks,
Lennart

I was wondering the same thing.

I think the Injection timing after Pilot means that the Main event happens as the Injection timing tables are set up and the Pilot happens X degrees before that defined by the Injection timing after Pilot table. I think if you remove the pilot injection it will still look at the B0720 table until you reach 2500rpms then it will switch to the B0721 table.

It seems like when the injected pulse is made larger to increase the amount of fuel the timing needs to be a larger number so the injection happens earlier BTDC. That way you can get maximum bang for the amount of fuel you supply.

My theory is:


The main injection timing is set by B0908,B0909, and B0910. The pilot injection timing is set by B0926, B0927, B0928, and B0929. The pilot injection timing is added to the main injection timing. Example: If B0910 is being used and the timing is 20 while chart B0929 is being used and that timing is 13, the pilot injection will turn on at 43 degrees and the main will turn on at 20 degrees. This is a basic explanation. Throwing in all the other tables w/ Baro, ETC, IAT, etc. complicates what I just explained.

I see I had the wrong tables. bobo has the correct tables. You can see from my sig what makes me tick...or miss.

Quote:

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Originally Posted by bobo

My theory is:


The main injection timing is set by B0908,B0909, and B0910. The pilot injection timing is set by B0926, B0927, B0928, and B0929. The pilot injection timing is added to the main injection timing. Example: If B0910 is being used and the timing is 20 while chart B0929 is being used and that timing is 13, the pilot injection will turn on at 43 degrees and the main will turn on at 20 degrees. This is a basic explanation. Throwing in all the other tables w/ Baro, ETC, IAT, etc. complicates what I just explained.

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If you could please help me out here, what is pilot injection timing and what is main injection timing?

Or for that matter, just what is pilot injection and main injection?

Quote:

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Originally Posted by Smokin LB7

If you could please help me out here, what is pilot injection timing and what is main injection timing?

Or for that matter, just what is pilot injection and main injection?

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I am wondering the same thing. I have read it sets up the pressure inside the cylinder before the main event occurs and reduces shock to the cylinder head and block.