PDA

View Full Version : Pilot Inections..off or on??



lubeman1969
August 24th, 2009, 03:00 PM
Can you guys chime in and tell me what are the benefits and or disadvantages of turning off your pilots? I have read some threads on it here and other places and cant quite get ahold of what Im looking to answer. I do understand it will be louder and possibly run rougher than normal. But, is it bad for your injectors? Someone also mentioned that post injection on the LBZ is useless?? Help me understand better...easy...Im new to this tuning stuff!!

DmaxHawk
August 24th, 2009, 03:06 PM
Dont think it would be bad for the injectors its just opening for one less interval. Post injection is used mainly for emissions. IIRC It is designed to reduces nox gasses. I have noticed that the truck sounds a little throatier with the post injection disabled.

lubeman1969
August 24th, 2009, 03:11 PM
Ok...thinking back, arent there only 2 tables for post injection?? Would I just zero these out? As far as emissions go, that means it will smell more at idle if I turn off the post injection? A mileage tune I downloaded off of DP has the P.I. turned off and I wondered what benefit this would be to mileage.

DmaxHawk
August 24th, 2009, 03:13 PM
Thats correct just zero them out. I havent noticed any more smell. Yes it would benefit mileage a bit. Since it is used after the expansion, it is basically wasting fuel.

lubeman1969
August 24th, 2009, 03:20 PM
Ok I'll do that..sounds like you have yours turned off already. If you have a minute when tooling around, will you list the table #'s for me...and are there others to change or only the ones dealing with post injection? Sorry to ask so many questions...Im so anxious to get more knowledgeable with this programming. I usually get head over heels with anything for my vehicles!!

DmaxHawk
August 24th, 2009, 03:23 PM
Tables are B9301 and B9302. Asking questions is always welcomed here, its a great way to learn new things

lubeman1969
August 24th, 2009, 03:29 PM
Would you do anything with B9201 and B9202? (post inj. #1 quantity and coolant adjust?)

DmaxHawk
August 24th, 2009, 03:30 PM
Negative, since they are already zeroed out

lubeman1969
August 24th, 2009, 03:31 PM
Cool...thanks Dmaxhawk...I will try this tomorrow! Signing off for dream land!! Take care man!

DmaxHawk
August 24th, 2009, 03:32 PM
Let me know how it goes. You too man

LBZoom
August 30th, 2009, 04:46 PM
Yes I too have disabled all post injections as they are a waste of fuel in the sense that they don't produce much in the way of power and I'm not concerned with the birth defects it will cause in the state of California lmao. I lowered my pilot injections down to 1.0mm3 across the board to save a little fuel but I didn't shut them down completely bc it sounds rough at idle and I like it kinda quiet, also it had a somewhat funky throttle response in my opinion. I was new to EFI about a year or a little more ago so anything I can do to help let me know!

justin123
September 2nd, 2009, 01:53 PM
i have no pilots or post injections on my LBZ and been that way for a while runs perfect and great just noiser at idle and i think it sounds better going up the road too from the exhaust but i have 5 inch stacks so u might not notice the exhaust sound if u got side exit but i do seem to get better mileage.. but u have to do some timing work when disabling pilots b/c the pilots preheat the cylnders and w/o them it will run like crap unless u advance the timeing. i just done a stock tune w/o pilots for a lmm waiting for him to test it out but my LBZ runs awsome. PM me if u have any questions later man

maxxflip
October 3rd, 2009, 04:54 AM
i have no pilots or post injections on my LBZ and been that way for a while runs perfect and great just noiser at idle and i think it sounds better going up the road too from the exhaust but i have 5 inch stacks so u might not notice the exhaust sound if u got side exit but i do seem to get better mileage.. but u have to do some timing work when disabling pilots b/c the pilots preheat the cylnders and w/o them it will run like crap unless u advance the timeing. i just done a stock tune w/o pilots for a lmm waiting for him to test it out but my LBZ runs awsome. PM me if u have any questions later man

still trying to get this no pilot tune into my truck and test it out
just been really busy the last little while and since my truck is my money maker the tow tune hasnt left it in over a month:) thanks justin ill let you guys know how it does as soon as i slow down a bit :cheers:

hondarider552
October 11th, 2009, 09:24 AM
so just set B9301 and B9302 all to 0 and done ?? seems too easy?

JoshH
October 11th, 2009, 01:23 PM
The best way to adjust pilot and post injection is with the max number of injection pulse table in the fuel pressure folder.

terryr85
October 12th, 2009, 01:38 PM
Ive tried turning off both pilot and post injections and doing nothing with timing and it runs like crap. Real rough idle

0well
October 13th, 2009, 01:59 AM
Josh, If I understand you correctly to remove post injection I would reduce the total number of injection pulses in the fuel pressure folder from 5 to 2?

bballer182
October 14th, 2009, 11:27 AM
Josh, If I understand you correctly to remove post injection I would reduce the total number of injection pulses in the fuel pressure folder from 5 to 2?

Yeah you can do that. But there is no way to know for sure that the post injections are the ones that are goin bye bye. so to know for sure set the injection tables to zero. I'm sure there is a table somewhere in the OS code that has the injection event in order of priority, but we don't have access to it. or it might not even be a table and it's hard coded into the OS.

justin123
October 15th, 2009, 02:20 PM
Ive tried turning off both pilot and post injections and doing nothing with timing and it runs like crap. Real rough idle

you have to advance timing or it will run like crap

bballer182
October 16th, 2009, 01:19 AM
you have to advance timing or it will run like crap

in timing table A

JoshH
October 19th, 2009, 04:59 AM
Yeah you can do that. But there is no way to know for sure that the post injections are the ones that are goin bye bye. so to know for sure set the injection tables to zero. I'm sure there is a table somewhere in the OS code that has the injection event in order of priority, but we don't have access to it. or it might not even be a table and it's hard coded into the OS.
Sure there is. Just log post and pilot injection. I tried the zero out tables method, but the injections were still active. When I used the max number of injection pulses table, the post and pilot injections shut off. This was on an LMM.

bballer182
October 19th, 2009, 11:03 AM
Sure there is. Just log post and pilot injection. I tried the zero out tables method, but the injections were still active. When I used the max number of injection pulses table, the post and pilot injections shut off. This was on an LMM.

Well i was referring if you use another value other than 1. If i had to guess i would guess that if you use 2 or 3 that the post injections would be the first to go the the ecm would pick off pilot #2 then pilot #1 last.

killerbee
October 20th, 2009, 01:44 AM
Sure there is. Just log post and pilot injection. I tried the zero out tables method, but the injections were still active. When I used the max number of injection pulses table, the post and pilot injections shut off. This was on an LMM.

I am asking because I don't know. If anyone knows, what is "volts" on the B1021 axis, refering to?

My (LMM) table begins at 1400 rpm. Any insight to the lower rpm's?

bballer182
October 20th, 2009, 11:03 AM
I am asking because I don't know. If anyone knows, what is "volts" on the B1021 axis, refering to?

My (LMM) table begins at 1400 rpm. Any insight to the lower rpm's?

The number of injection events is based on the voltage because if there is not enough voltage the injector open and close times are obviously slower, hence, the table. Lower voltage = less number of injection events the injectors are capable of.

There are similar tables in gas tunes as well.

dunno about the rpm break point though...

killerbee
October 20th, 2009, 11:08 AM
voltage of what? I am ignorant on matter of injection control.

bballer182
October 20th, 2009, 11:21 AM
voltage of what? I am ignorant on matter of injection control.

It's either battery voltage or voltage supply to the ecm.

SAE.VPWR is the pid that displays voltage supply to the ECM. I cranked out a TON (literally) of cal_links for Ross that are going to be released on the new public release of 7.5. and that was one of the links i added along with ALL of the DSP tables, 20 or so for the LBZ/LMM and 15 or so that are LMM specific. I attached it if you want it before the next release. It's nothing secret or anything.

And it only took me 2 hours! :shock::shock:



EDIT: just upped a new version i just added 20 LMM tables. Final version all tables in LBZ and LMM has links now.