Pilot Injection!! Can it be turned off??? Anyone know?

Big Swole

Big Swole

MegaInterceptor
Joined
Jun 28, 2007
Messages
16,950
Jeff and I have been doing some brain storming about my extreme rattle / clatter at low rpm / low boost!!

On the 04.5 trucks we have pilot injection events.....When you couple that with large injectors (my 3.3's) and Dual cp3's, We assume that it makes that pilot injection event pretty dang large!!

With my cut pistons, large injectors, duals, and then you add the Smarty and Mp8 to the mix.....We think that my truck has Stupid crazy timing right off idle..

We believe that if we could turn OFF the pilot injection event that my rattle / clatter would go away and my HG and cylinder walls will love me for it!!!! lol



Does ANYBODY know if it can be turned off.....Has Marco / Bob or Any other programmer company experimented with this.......

I did speak to one company the other day the guy I spoke with believes it can be done but I would have to pay for a custom tune and would possilby have to order Several units to be sold!! Not something I can afford!!

Is the Bosch Stand Alone controler the ONLY way this could be acheaved???
 
Marco tried it and said he lost like 100hp on the dyno, not sure if it could be something that could turned on up in the rpm range or not.
 
I bet Marco can, the got rid of the 3rd event and found that it lost power.
 
yep, Marco found it and disabled it with the outcome the others mentioned. I major loss in power.
 
You know, I remember Don saying he could give you a tune for a pressure controller, that could lower rail during low map conditions.....I'd say its worth a try. Like a mp8 that would go below zero....

Adjustabilty would be key....just like a mp8 only down with the pressure.

Ideally it would have 2 knobs, low setting low boost, high setting high boost....


Not sure of a % that this would work.....you trick the ecu into lower rail, and it will have to compensate with duration..... BUT I think it only compensate with main event duration, not pilot quantity.

Worth a try......you know the chance of getting a custom tune.....LOL


That rattle/knock 100% comes from lower compression, it showed up after I started tweeking rods. (lowered compression due to a shorter rod)
The ecu starts the pilot when there should be enough heat, and when there isn't....it lights off hard instead of controlled, when the cylinder temp reaches auto-ignition.
 
Its not the third event that needs to be turned off, its adjustment of the pilot injection. (more late)

And for that matter compensation with the main event.
 
see Swole.... my wife was right, it's the " magic " rattle and without it.... you have no go go. Just pretend your truck is now a all out racer and that's what they sound like:rules:
 
I suspect there's something in the programming that can not be changed. Yes, macro can turn off the 1st and 3rd. However, can he move the 2nd around enough? Why? P-pumps run fine with one event. VP44's run fine with one event.

So, if you have for a normal map on a CR:

|----|--------------------|----|

And you remove the extra events do you have this to play with?:

| |--------------------| |

or the entire range?

|------------------------------|

I suspect we only get the middle ground and with in a defined range of that middle ground, other wise, Macro could program in a later pilot or an earlier main and the truck would run like a VP44 or 12 valve truck.

Or the guy is keeping quite and/or the technology for the trucks he sponsors.

I know nothing technical about the cummins ecm and what restrictions it operates within, and Macro/bob have never corrected my theories. So. Would someone shed some light on the topic here?
 
The pilot injection helps spool the turbos. The dmax guys have tried that with efi live and they said it hurt spoolup somewhat.
 
Joesixpack said:
You know, I remember Don saying he could give you a tune for a pressure controller, that could lower rail during low map conditions.....I'd say its worth a try. Like a mp8 that would go below zero....

Adjustabilty would be key....just like a mp8 only down with the pressure.

Ideally it would have 2 knobs, low setting low boost, high setting high boost....


Not sure of a % that this would work.....you trick the ecu into lower rail, and it will have to compensate with duration..... BUT I think it only compensate with main event duration, not pilot quantity.

Worth a try......you know the chance of getting a custom tune.....LOL


That rattle/knock 100% comes from lower compression, it showed up after I started tweeking rods. (lowered compression due to a shorter rod)
The ecu starts the pilot when there should be enough heat, and when there isn't....it lights off hard instead of controlled, when the cylinder temp reaches auto-ignition.
Click to expand...


Yeah, I've been in contact with Don and he's shed some light on a few issues....I've been waiting on my RP gauge to come in. It's been on Back order...Don wants me to wait until I get the gauge on it so I can let him know what's it doing......He has said wether or not he'll hook me up with the custom box or not......He already done so much for me, I hate to bug him too much....But if it'll help, I really hope I get the chance to try one...

Well Dang!! If it's 100% from my lower'd compression, I almost wish I could go back in time on my build...I probably still cut them a little but no where near as much as I did.......But your theory makes total since though.....I guess decompressing a 12V and vp trucks works great and thats why Jeff's done if for so long, but these dam 3rd gen trucks with the 3 injection events a Total different animal!!

Any other idea's on how to fix this for me??????....I might try a 12v injector washer to try to lower my injector in the bowl a bit....I'm just not sure about how well the crossover tubes will seal up....Once I get my gauge, maybe Don will let me try his pressure box........I just don't want to have to REBUILD my whole engine again to get rid of it!!!!!!!:bang
 
You know, when I first me Jeff a long while ago....He was talking about an idea of having someone write a program for the CR's that has only 1 injection event...I bet we may see more power, Better mileage, and the old school sound from these CR's

I wonder if anyone will ever do it...Or if they have, what were the results??
 
triton said:
see Swole.... my wife was right, it's the " magic " rattle and without it.... you have no go go. Just pretend your truck is now a all out racer and that's what they sound like:rules:
Click to expand...



I can learn to live with the rattle I guess but what I won't be able to stand is the possible damage from it!!! Cylinder wall damage and Blowing HG's from the stupid timing that it's creating.....

But, I'd much rather have my smooth sounding engine back so it doesn't sound like it's coming apart while driving around town....I like people fearing my truck, but not from them thinking that thier about to get a rod slung out into the side of thier car!!!!:bang
 
Hey Swole
Is this issue your having a potential bad thing or just an annoying rattle you need to get use to?
 
nrussell said:
Hey Swole
Is this issue your having a potential bad thing or just an annoying rattle you need to get use to?
Click to expand...


Hey man!! Haven't heard / seen ya in a while!!

Well, honestly I don't really know it'll cause issues / damage but in theory it should!!!!

I just want to get it fixed as much as possible for both reason's!! To prevent future damage and to feel better about driving my truck!! I've said before that it really makes me NOT wanna drive it cause it sounds so bad!! It's down right embarrasing!!:bang

At the track, I won't give a chit, but on the street......UGH!!!!!
 
How low did you guys go with compression? I just did a 15:1 motor that had hardly any noises out of the normal for a set of 5.1's
 
I don't think its a bad as it sounds, yours rattle goes away under full load and boost right?

I'm not poo-pooing lower compression either....just we need our electronics to deal with it....
 
I thought you guys might be at the suncoast redneck nationals, but i guess not. I need Jeff to install my cam and springs. I have a job in the virgin islands in the middle of march and will probably drop it off before i leave. See if jeff will put different pistons in from the bottom while it's still in the frame, just an idea. i believe he replaced the rings on my pistons that way. you guys did a great job on that install too, sucks about the rattle though!
 
lmills said:
How low did you guys go with compression? I just did a 15:1 motor that had hardly any noises out of the normal for a set of 5.1's
Click to expand...


We cut a hundred thousandths off the top !!!!

I never really realized how much it really was until now...I'm realy not sure on what that make my actual compression ratio!! You have any clue....???

Jeff says the hundred is normal for a 12v build but that due to the larger bowl and less piston top of a late CR piston, that it really doesn't lower it as much as a 12v.....

Don did mention a while back when I First got my build done that " maybe a larger set of injectors would help".........How would going larger on my injectors help cure this noise???? If so, then GREAT!!!!! more power and less noise!!! I'll take it!!!!
 
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Joesixpack said:
I don't think its a bad as it sounds, yours rattle goes away under full load and boost right?

I'm not poo-pooing lower compression either....just we need our electronics to deal with it....
Click to expand...



OH yeah!!! around 8-10 psi of boost (on it's way up) it almost completely goes away!!!


It's ok...I respect ALL opinions here..I'm the one trying to learn from all you guys!! Thanks for any help and opinion's!!!

Your totally right!! The programming just needs to evlolve somemore..... I guess I need to save for a Bosch Stand-Alone!!! HA!!!!!:bang
 
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