EFI tuning - Where are all the good resources?

Big Block 88 said:
The timing question is actually quite simple. Increase timing tell piston cracks and then back it off a bit
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I can see it now...one of them will have the tables max out at 45°...or whatever the max efilive will allow it to go lol....

FWIW i dyno at 32° on stock injectors. Race and pull with 30. Not sure what the norm is for cummins though.
 
The software isn't bad to understand once you get a basic understanding of what does what. I know for teh DMAX you don't simply change it from say 100MM3 of fuel max to 150MM3 of fuel. The ECM has internal limits to only send out 100MM3 of fuel, but you can change your pulsewidths essentially doing thesame thing. Also by being able to change your pulsewidths at different RPM's and pressures, you can actually tune it to hold rail pressure better by being it to make it not get alot of pulsewidth until the rail pressure is built up and by setting it up so that if your rail pressure drops so does your pulsewidth essentially helping you to hold as much rail pressure as your system can supply. And if you compare 10 different tuners, you will find 10 different ways of accomplishing the same goal. There is alot left to the tuners interpetation as to how you want it to come in and or where you want it to come in. And with the ability to change timing for both the main and pilot charge independantly at fine increments, making a turbo light off is greatly improved. I know I am one of those guys who takes a small up in fuel and sits down and tweaks it until I feel I have gotten the max out of it, then I will use that and build up from there until I got to where I wanted to be at. I have a PPE 6 that somebody gave me to try and that thing fuels with a HUGE amount of fuel, but yet I have a simple 40% over tune that runs almost as strong without all of the lag and blinding clouds of smoke. Head over to the DMAX forums and see what others are doing, and look at some of the tune files in teh libraries and see what they did to get there. Then look at the guys who push the envelope and say 40 degrees of timing with a 3500 pulsewidth on 60 over sticks with a dual CP3 set-up, and then see the aftermath. The CUMMINS tuning is starting over, but at least there are some general guides to follow from others.
 
What do you bet in a year they are going to be regretting helping once the cr's start dominating LOL :poke:
 
I thing I have been wondering is when you increase the hole size of the injector aren't you injecting more volume of fuel than the software says you are? How do you accurately tell how much fuel volume you are injecting with modified injectors?
 
Yeah for sure, and if you can't modify the mathematical parts of the ecm then it comes down to tweaking the tables to do what you want, and the actual values of the table become less relevant.

For example with the larger nozzles, the off boost volume becomes too much....so you tweak that area of the injector conversion table down......now we've put a hell yeah set of compounds on and our fuel on boost is still to low....so you tweak that part of the table up all via pulse width.

Were as on a true stand alone, my injector conversion table accurately represents my injectors, and start out the calibration with a max fuel amount of my choosing and limit down with calculations.

Sounds like you could load your favorite smarty setting and then pull it with efi and tweak it right.......
 
Joesixpack said:
Yeah for sure, and if you can't modify the mathematical parts of the ecm then it comes down to tweaking the tables to do what you want, and the actual values of the table become less relevant.

For example with the larger nozzles, the off boost volume becomes too much....so you tweak that area of the injector conversion table down......now we've put a hell yeah set of compounds on and our fuel on boost is still to low....so you tweak that part of the table up all via pulse width.

Were as on a true stand alone, my injector conversion table accurately represents my injectors, and start out the calibration with a max fuel amount of my choosing and limit down with calculations.
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I can't speak for how it will work on the Cummins, but on a Duramax, you adjust your pulse width table to the maximum amount your CP3 will keep up with or the maximum amount you want to run. For example, on my stock LBZ injectors, I can run over 3000 uS (microseconds) and still maintain 26k PSI of rail pressure, but if I were to put some 40% over injectors in my engine, I would have to drop the pulse width down closer to 2400 uS to maintain rail pressure.

To control smoke on a Duramax, there is a table that references the MAF sensor, and you can adjust how much fuel the truck can use at a given air quantity and engine RPM. I assume there is something similar in the Cummins ECM that references the MAP sensor.

There is really no advantage to the ECM knowing the actual fuel quantity. I like to think of it as more of a reference number. The only "problem" with adjusting the pulse width table is the truck's fuel mileage display typically becomes even more inaccurate.
Joesixpack said:
Sounds like you could load your favorite smarty setting and then pull it with efi and tweak it right.......
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When it comes to custom tuning software, that is about the biggest ethical no-no there is. It is highly frowned upon in the Duramax community, and I'm sure anyone trying this with their Cummins will receive little to no help from any experienced tuners.
 
thanks Chris and Josh that's kinda what I was thinking. Using the number for a reference, with OS like efilive.
 
JoshH said:
There is really no advantage to the ECM knowing the actual fuel quantity.


When it comes to custom tuning software, that is about the biggest ethical no-no there is. It is highly frowned upon in the Duramax community, and I'm sure anyone trying this with their Cummins will receive little to no help from any experienced tuners.
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Its a HUGE advantage from a calibration standpoint, in simple raw calculation you know the smoke limits via air fuel ratio, plunk in your calibrated injector data and bingo, no smoke from simple calculated air-fuel ratio. (Running a stand alone) Most that work tuning in OEM or after market stand alone's would tell you modifying the injector calibration table to do what you want is the a$$ backwards way of doing it.........BUT thats what you have to work with with a hacked ecu and it does work well!


AND....I see absolutely NO moral issue with buddy loading up his smarty tune that he payed for.....then pulling it with a efi tool that he payed for, and then tuning it specifically for his vehicle.

I see one "tuner" already posted a table from a "box"........
 
joefarmer said:
I have to wonder if Efilive is making Marco/Bob pucker a little?
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Ha, I think thats a safe bet.

Bob's a great guy and has helped me, but I can tell you now when EFI comes out I'll be off the smarty wagon. With a single charger and elevation I really need better tuning to keep the smoke down. If I don't go standalone before that point. They're both great guys and I wish them well, but box tuning just isn't for me!
 
Joesixpack said:
Its a HUGE advantage from a calibration standpoint, in simple raw calculation you know the smoke limits via air fuel ratio, plunk in your calibrated injector data and bingo, no smoke from simple calculated air-fuel ratio. (Running a stand alone) Most that work tuning in OEM or after market stand alone's would tell you modifying the injector calibration table to do what you want is the a$$ backwards way of doing it.........BUT thats what you have to work with with a hacked ecu and it does work well!
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It might be easier, but I wouldn't say it would work any better. In order to populate the table, you would need to know exactly what pulse width to run at every pressure to achieve your desired fuel quantity. You would need to get this info in a chart from your injector manufacturer/shop. Say you have injectors that flow 240 mm3. You just take that chart and enter the 20 mm3 data in the 10 mm3 spot, enter the 40 mm3 data in the 20 mm3 spot, 60 mm3 in the 30 mm3 spot, so on and so forth until you get to 240 mm3 in the 120 mm3 spot. Then you have successfully rescaled the pulse width table to the new "fuel quantities".

However, the fact of the matter is, I have never bought, seen, or heard of a set of injectors that break down all that info in a chart like that. I have heard of some that come with flow data, but I don't think it is as detailed as you would need to properly populate a pulse with table with 100% accuracy. As you said, doing in the method that is used in a hacked ECM does work, and it works very well.
Joesixpack said:
AND....I see absolutely NO moral issue with buddy loading up his smarty tune that he payed for.....then pulling it with a efi tool that he payed for, and then tuning it specifically for his vehicle.

I see one "tuner" already posted a table from a "box"........
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It's fine as long as he never sells the tuner he modifies. The problem comes when someone downloads their Smarty/PPE/Bully Dog/Whatever tune, make changes to get it how they want it, then they say, "I don't need this thing anymore", and they sell it on the forum or eBay or Craigslist or whatever. Most won't stop using the tunes they modified after the sale. I'm just letting you guys know it is a pretty stick subject in the Duramax world.
 
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Id have to say efi cummins will be sweet and once again us cummins ppl will say so long d max and we will kick there ass all over again if you know how to tune that is....
 
JoshH said:
It might be easier, but I wouldn't say it would work any better. In order to populate the table, you would need to know exactly what pulse width to run at every pressure to achieve your desired fuel quantity. You would need to get this info in a chart from your injector manufacturer/shop. Say you have injectors that flow 240 mm3. You just take that chart and enter the 20 mm3 data in the 10 mm3 spot, enter the 40 mm3 data in the 20 mm3 spot, 60 mm3 in the 30 mm3 spot, so on and so forth until you get to 240 mm3 in the 120 mm3 spot. Then you have successfully rescaled the pulse width table to the new "fuel quantities".

However, the fact of the matter is, I have never bought, seen, or heard of a set of injectors that break down all that info in a chart like that. I have heard of some that come with flow data, but I don't think it is as detailed as you would need to properly populate a pulse with table with 100% accuracy. As you said, doing in the method that is used in a hacked ECM does work, and it works very well.
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Do you enter in every pulse width for every pressure?? No of course not, you populate a table be it 16X16, 20X20 and extrapolate.

I can guarantee you its 100 times better when you have calibrated data PROVIDED you are running a standalone and have complete control. Actually I'd still like the data even modifying the stock tables, it would still be less jerking off in the dark.

Seems to me my injectors were tested at 8 pressure points, but it was more than enough to get a great calibration right off the bat.

I see Exergy is giving out flow data, Bosch did mine.
 
Joesixpack said:
Do you enter in every pulse width for every pressure?? No of course not, you populate a table be it 16X16, 20X20 and extrapolate.

I can guarantee you its 100 times better when you have calibrated data PROVIDED you are running a standalone and have complete control. Actually I'd still like the data even modifying the stock tables, it would still be less jerking off in the dark.

Seems to me my injectors were tested at 8 pressure points, but it was more than enough to get a great calibration right off the bat.

I see Exergy is giving out flow data, Bosch did mine.
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I don't doubt you at all. I'm sure it is 100 times easier to tune when you have really good injector flow data, but I have never had that advantage. I've never seen any of the flow injector flow sheets. When you say they tested them at 8 different pressures, did they use the same pulse width at all the pressures or did they keep the fuel quantity the same and change up the pulse width or both?
 
Pressure along the vertical axis, uS along the horizontal. The stock injector was a pretty gradual slowly rising line, my modified injectors blast off at 45% angle. The steeper we can get that line the more we can inject in the short window at high RPM.
 
Joe,

All your calculations for mm3 flow values are assuming the psi at the tip of the injector match the actual rail psi sensor reading for each injection event. That's a bull**** theory right from the start if I've ever heard one.
 
Bobo said:
Joe,

All your calculations for mm3 flow values are assuming the psi at the tip of the injector match the actual rail psi sensor reading for each injection event. That's a bull**** theory right from the start if I've ever heard one.
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LOL....you want to tell me you incorporate pressure wave dynamics in your calibration and some how you measure that.

For emmisions, yes....to me deadly accurate on small pilot events you need to take into account the pressure sine that results from the valve event.

For our crude hot roding please.....and for that matter, once we hog out our injectors forget about ever being that accurate on the pilot shot again.
 
Joesixpack said:
LOL....you want to tell me you incorporate pressure wave dynamics in your calibration and some how you measure that.

For emmisions, yes....to me deadly accurate on small pilot events you need to take into account the pressure sine that results from the valve event.

For our crude hot roding please.....and for that matter, once we hog out our injectors forget about ever being that accurate on the pilot shot again.
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It's not "calibrated data" if you're just guessing. A mm3 value in the ECM is a calculated value derived from sensor inputs from the driver compared to sensor outputs from the drivetrain and motor. The calculated value used by the ECM is only a reference point to get the engine to respond to driver inputs, but it is calibrated for control based on factory specifications. There is no reason this value needs to be derived from "calibrated data" as long as the values the ECM's calculated mm3 value is refrencing are "calibrated" to reflect the increased actual fuel flow numbers or desired fuel flow numbers. A factory calilibrated computer might never desire flow above 100mm3, but I can make it flow 150mm3 by increasing the parameters the commanded 100mm3 value references to get 100mm3 of factory calibrated fuel. The ECM does not need to know an actual flow value, because I have control of all the values the commanded flow value has control over.
 
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