LB7: Tuning Out Pilot Injection

[WisconsinHick1]

Has anyone built a tune that doesn't have pilot injection? What would need to be done to achive this? I am looking at trying it for my street truck to see if that is part of my tuning issues I have been having.

Thanks in advance for any direction.

 

[PureHybrid]

It would probably idle like sheet and sound awful lol, but I'm sure its been done. I would assume just zero out the qty and compensation tables, more timing on main inj. Might be a lot easier with a roadrunner ecm since you have an lb7 IMO.

 

[02greysixer]

I think Ferm tried it in his suburban conversion and said it sounded like a 7.3 p.s. maybe he'll see this and share how he did it

 

[pizza pig]

pretty sure a lot of tunes out there have pilot shut off at WOT once at certain RPM. correct me if im wrong.

 

[PureHybrid]

Yes, but I'll jump on a limb and say that's not what he wants to know.

 

[WisconsinHick1]

Yeah I'm looking for information on it being shut off completely. Where do I need to add or take away timing or pulse. I know of a couple pullers that have tunes without pilot.

 

[onebaddmaxxx]

Timing seems to be the biggest factor, but have seen sometimes where main pulse is changed at idle along with pilot pulse and cause a small lope to it from fueling heavy. I wouldn't disable it except after 2800rpm (WOT as thats the only place it needs to be disabled then base all your fueling off of main injection pulse and 1 timing table. (for ease of tuning and a little more fuel pressure from not having multiple injection events.

On your truck (I think its an lb7/lly) You would go into the pilot injection tab, then go to injection quantity. Turn the 2800+ rpms and 80mm3 section and on to 0. Iv seen a few trucks pick up some rail psi

 

[PureHybrid]

Hell turn that crap off at 2200, we're trying to make power!

 

[onebaddmaxxx]

Na....Too noisey. rattles . lol

 

[THEFERMANATOR]

Yep, it rattles just a bit. And not to mention the blue smoke. I ended up cranking the rail pressure up to 80 at idle to clear out most of the hazing, and timing had to go up to around 8 degrees at idle. Made her sound like she was eating rocks, but it was the only way to get it to idle without smoking blue HEAVILY! It still puffed blue anytime I stabbed the throttle, and I personally thought it made it laggy. I had mine on a DSP2 so I could shut it off at will(never could get it to work on a DSP5 because the DSP pilot injection timing tables don't work), and the BURB just turned lazy whenever I flipped it ov er to the pilot less tune. I do turn pilot off around 2400 or so now to help with upper end spool, but under low engine loads pilot really helps to keep it cleaned up, and responsive.

Heres the LB7 eating rocks, you can hear the difference right at the end where I turn pilot back on.
http://www.youtube.com/watch?v=HcZh05Y76M8

 

[THEFERMANATOR]

Hell turn that crap off at 2200, we're trying to make power!

That's fine and dandy until your loaded up with the family, travel trailer in tow, heading into the mountains, and the pilot kicks off at 2200 and the wife goes balistic because she can't sleep over the extra rattle. So it gets turned off at 2500 so it stays on until I start getting into the power.

 

[WisconsinHick1]

Well then I might have to leave it. it's only a street toy but I don't want it loud and annoying.

Also might have to cut the pilot out at 2400 but I have an S475 with100% injectors and might need some more pilot up to 2600 where my converter stalls to.

 

[Dmax87]

What would be the benefit of turning pilot off at higher rpms?

 

[PureHybrid]

That's fine and dandy until your loaded up with the family, travel trailer in tow, heading into the mountains, and the pilot kicks off at 2200 and the wife goes balistic because she can't sleep over the extra rattle. So it gets turned off at 2500 so it stays on until I start getting into the power.

Not just at 2200, but anything over 80mm3 AND 2200. You won't notice the noise when its making a decent amount of boost.

 

[paint94979]

More god damn power

 

[Dmax87]

Does tuning pilot out at higher rpm allow for more main pulse to be added or am I thinking wrong here?

 

[onebaddmaxxx]

Your right.

 

[Harbin_22]

I have noticed lower EGTs with pilot on in the high RPMs, but you can maintain better RP with it turned off. It is off in all my tunes above 2400 I think

 

[Harbin_22]

You will get a bigger main pulse but with pilot on you get couple hundred pulse from the pilot than a little smaller main pulse to get the similar amount of fuel

 

[gmc502]

could someone show the newbie tuners a screen shot of just how your turning the pilot pulse off?
I'm pretty sure I know how but would like to check it out first.