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2006Cummins
September 25th, 2011, 12:13 PM
Was wondering if there are any advantages of playing with the pilot injection at all. I have 50hp injectors, so I was thinking about reducing the pilot a little to compensate for the increased fuel, and help reduce smoke. What do you guys think?

Mike

2007 5.9
September 25th, 2011, 03:13 PM
Yep...it will help.

Start with small changes

~Les

2006Cummins
September 25th, 2011, 03:56 PM
Ok. Should I start by subtracting a small percentage (5%?) thru-out the entire pilot pulse table? My injectors are roughly 18% larger than stock - so could subtract up to 18% before injection less than stock? Thanks.

Mike

2007 5.9
September 26th, 2011, 12:39 AM
Start with smoothing of the tables...rid the tables of peaks and valleys...get it more uniform and smooth.

See how that feels...then begin to take away %...you can start at 5% and go from there.

~Les

2006Cummins
September 26th, 2011, 03:26 AM
Roger that.

Mike

2006Cummins
October 1st, 2011, 03:55 AM
I smoothed out the pilot pulse graph a little and then subtracted 5%, 10%, and 15%. It runs fine, but anything over 5% will give me some white smoke if I bring the rpm's up to 2k and let off (while parked). Didn't notice much difference otherwise.

Mike

2007 5.9
October 1st, 2011, 04:30 AM
If you take out too much in the low rpm areas, it disables pilot in those areas and youll get white smoke.

~Les

AdamRRT
October 1st, 2011, 01:16 PM
Hrmm I've got a single event tune that I gives me no white smoke.

2007 5.9
October 1st, 2011, 04:25 PM
Hrmm I've got a single event tune that I gives me no white smoke.

Did you compensate main timing??

~Les

AdamRRT
October 1st, 2011, 04:44 PM
OH is that what you were saying? My bad. I thought you meant ANY single event tune. I'll STFU now. :(

2007 5.9
October 1st, 2011, 05:01 PM
I was explaining that if you take pilot away without compensating for it..you'll get white smoke.

You can do it either by removing pilot completely or take too much out. Less than 1.5-2mm3 can disable it.

~Les

AdamRRT
October 1st, 2011, 05:08 PM
Yeah I missed that. I thought you meant if you take it out at all. My apology for chiming in.

AdamRRT
October 2nd, 2011, 06:47 AM
Crap! This was the coldest morning for me to start the truck with the single even tune on. 48* F. I got white smoke for almost a full minute on startup.

I'll end up keeping some small pilot on startup and at parking lot speeds (so it doesn't sound like garbage), and fade into a single event.

olboyowl
October 2nd, 2011, 12:01 PM
did the same for me a few weeks ago. have pilot back on now. gonna start pullin it after 1500 rpm and see how it runs. got the next three days off for hunting and will play with this in between. will post results

olboyowl
October 5th, 2011, 01:29 AM
so, monday i tried phasing pilot out after 1500rpm to have it completely shut off by 1700. truck didnt like it. as soon as it hit 1600 (and got below 3mm3) it started throwing white smoke and shaking. temps were in the 40's and truck wasnt warmed up yet. i'll play with it some more when i get a chance

AdamRRT
October 5th, 2011, 01:55 AM
Dang son you revving past 1600 cold? Sounds more like you didn't compensate timing after removing it, to me. But I could be SO wrong.

olboyowl
October 5th, 2011, 02:18 AM
no, not revving at 1600 at idle cold. gave it about 2-3 minutes and took it for a drive. my bad. forgot to type that. also, timing was compensated for.

2007 5.9
October 5th, 2011, 02:39 AM
Sounds like not quite enough timing added...what is your values for timing once pilot is removed??

AdamRRT
October 5th, 2011, 04:42 AM
That's what I think too. That's what I was trying to get at, but with my limited experience I need guys like you to chime in to verify.

olboyowl
October 6th, 2011, 01:27 AM
sorry for the delay. got to trackin a deer last night and didn't have time. don't have my laptop on hand but from memory, i would say between 25-30* with the bias from 1500rpm and up. again, won't be able to verify till tomorrow and might be wrong.

MQ105
October 6th, 2011, 10:42 AM
Les, are you saying that if less than 1.5-2mm3 is commanded as pilot, the pilot event may not happen at all?



I was explaining that if you take pilot away without compensating for it..you'll get white smoke.

You can do it either by removing pilot completely or take too much out. Less than 1.5-2mm3 can disable it.

~Les

2007 5.9
October 6th, 2011, 11:54 AM
Sorry i put the wrong values in there.... anything less than 1.0-.5 has killed pilot on both my truck and sled puller.

Sorry for the misleading info.

~Les

MQ105
October 6th, 2011, 12:59 PM
The pilot doesn't happen at all if commanded volume is less than that amount?

2007 5.9
October 6th, 2011, 01:02 PM
The pilot doesn't happen at all if commanded volume is less than that amount?

This has been my experience

~Les

MQ105
October 6th, 2011, 01:10 PM
That's good to know.