Pilot Injection Tuning

[wdino73]

I've got a couple of thought about Pilot Injection please don't burn me at the stake for these thoughts,,
Alot of people including myself turn off the pilot after 2000rpm an 70 or 80mm3,
I've notice in the stock tune they began cutting it back some from 1.0 to as low as 0.797 at 2600rpms an at 25mm3, what about going in the table were the stock tune starts cutting it back an subtract the % of your injectors over, say mines 45% overs so in theory u would still be adding pilot at the high rpms but your telling the tune to allow for the bigger injectors, which will take the low to 0.438
Is this a stupid thought or is it genius???:rofl:
All positive input is appreciated..

 

[THEFERMANATOR]

Also keep in mind that pilot cuts off once you drop below a set point(.938 IIRC stock), so even though it shows a value it doesn't meen it's active.

Check out the parameters tab under pilot injection and you'll find that there are several limiters that work with pilot injection.

 

[wdino73]

Also keep in mind that pilot cuts off once you drop below a set point(.938 IIRC stock), so even though it shows a value it doesn't meen it's active.

Check out the parameters tab under pilot injection and you'll find that there are several limiters that work with pilot injection.

If I put in the new lower value, then u would have a new bottom or does it work that away???? Cause the lower limit is -0.200

 

[THEFERMANATOR]

You can go into the parameters and lower what the minumum amount is and then lower the main table. The problem comes in with injector lag. The injector will have a certain amount of delay in it when opening, so if you make the injection event to short it won't inject any fuel. You have to have a certain amount of injection time in order for it to be able to inject any fuel rather than just sending a an electrical pulse that won't do anything at the injector.

 

[Mike_S]

You can go into the parameters and lower what the minumum amount is and then lower the main table. The problem comes in with injector lag. The injector will have a certain amount of delay in it when opening, so if you make the injection event to short it won't inject any fuel. You have to have a certain amount of injection time in order for it to be able to inject any fuel rather than just sending a an electrical pulse that won't do anything at the injector.

Exactly. The minimum pulse width, or minimum injection amount is there to save unnecessary ECM (or FICM?) processing load. There is no sense in processing, timing, and delivering a pulse signal to the injectors that is shorter than the time it takes for the injector to even open.

Also, something to think about, On Jakes truck we dialed back the pilot pulse width to account for larger injectors...and ended up bringing it back up. The results were not great with the larger nozzles and "stock" (compensated) injection amounts. The cylinder burn was not hot enough and we ended up with excessive cold-smoke poor throttle response and some clag.

 

[TrentNell]

I rarely change pilot other than reducing the pulse width tables a bit for larger injectors , unless i am getting noise ( clatter ) , and of course turning it off under WOT .

 

[SSchmi5519]

I rarely change pilot other than reducing the pulse width tables a bit for larger injectors , unless i am getting noise ( clatter ) , and of course turning it off under WOT .

Theres a key pilot table that needs to be looked at when running BIG injectors...besides pulse.

 

[TrentNell]

Theres a key pilot table that needs to be looked at when running BIG injectors...besides pulse.

I was referring to the size injector's Dino is running ,there not monster sticks.

 

[wdino73]

yeah I got baby sticks
I was trying to learn something thought I would ask, I remember what u showed me on the pilot pw Trent, I was just doing some playing an thought I would ask about this, not alot of info on pilot,,,, Thanks for your responses :thumb: