Low Smoke/ Smokeless Power?

[2006Cummins]

One of the main reasons I got EFIlive was to reduce or eliminate smoke. I have been working on making tunes that will have decent drivability, make good power, and DON'T SMOKE. So far, I have not been too successful. I am looking for some input from those who have succeeded with this. I know that it depends on turbo, injectors, truck has to be in good mechanical condition, etc., but I am looking for some general guidelines as far as tuning is concerned. I know that too much duration or pressure too early, not enough boost or timing on the top end, etc., will cause smoke. What I am looking for is something like "use the least amount of timing and duration down low with a small amount of post injection until the turbo spools-up, then ramp up duration while slowly adding pressure and timing, and eliminate pilot injection above 2600rpm, bla bla bla." I have been playing with increasing/decreasing timing, pressure, and duration over the past few weeks, as well as working with the boost limiter. I have excluded post injection completely, and reduced pilot some. If the exhaust is clean during normal acceleration usually I cant get very good response, and if I get it to where it is responsive, I have a slight haze under moderate acceleration. What I would like is 600-625hp with only a moderate haze on the top end. With the bully dog, and quadzilla xzt box that I was running, I had no smoke on moderate acceleration with good response, but way too much smoke with anything beyond that (at full boost and high rpms it was ok), and made 621hp.

Mike

[icemanjc1]

What's all done (mods) to your truck?

[2006Cummins]

64/71/13ss turbo, Volant CAI, ATS intake and exhaust Manifolds, DDP 50hp nozzles, 4" exhaust, 100gph lift pump, Floor-It Stage 3 CP3, Banks CAC.

Mike

[TexasCummins]

Subscribed.

[2007 5.9]

Timing and low mm3 duration is critical to smoke control. Keep the timing low until turbo is spooled and then increase timing...also keep the duration low until power is needed then add duration back in. When i started to mess with duration, my truck would barely run then I added duration until I saw smoke then backed off.

Its really a trial and error thing for smoke control...

[DoghouseDiesel]

Just to expand on what Les said, when you're messing with the duration, you'll know when you've brought it too low. What will happen is the ECM will simply command higher mm3's to meet the duration needs to keep the motor idling smooth. This is your start point.

Bring the duration down until you see the mm3's begin to rise and note the duration values.

Can't really give you a set value as each truck and set of injectors is a little different. But, for example, on my truck, it likes to idle with a duration around 750 - 775 and under daily driving boost conditions (15 psi or less) if I see duration above 1800, I get smoke (or at least a haze). My normal daily driving range is in the 30mm3 - 70mm3 range so those are the areas I concentrate on as far as smoke control.

But yes, low timing moves the injection event later in the cycle and retains more heat to spin the turbo and get it moving. Higher timing produces more power, but is slower to get the turbo going and produces more smoke.

It is quite a bit of trial and error.

[2006Cummins]

This is the kind of info that I am looking for.:) Thanks for the input. Any other thoughts would also be appreciated. I have really been cutting back on low/mid-range duration, but I think I'm going to really neuter it this time.

Mike

[CIDRAUGHN]

I have had real good luck with what was stated above, keeping the duration low until boost comes up, keeping timing low until it is spooled, and also the most luck I have had is the F0502 table, boost limiting the fuel. Im spooling a BEP S466 66/87/1.00 with 110% injectors with nothing more than a minor haze with foot on the floor from 1500 rpm up. Using the JoshH timing calculator helped considerably on power, and smoke, but I found I needed to lower timing a few degrees on the top end to get more power. When using F0502, knowing when your turbo will light is essential, and yours will light much sooner than mine. I should also mention mine is a 6 speed as well. The tune I have now pulls hard from 2000 RPM all the way to 4000+.

I should also add, F0502 is tricky, 14.7 psi is atmospheric pressure, and reads 0 psi on your boost gauge. Once I figured that out, through logging, it was amazing how I could control the smoke.

That being said, I have had zero luck out of the E2567 Equvalence Ratio limiting table. I make changes to it and nothing happens. Could have something to do with not having stock injectors though.

I havent been able to achieve max power with no smoke, but this is a little more difficult with my setup. I do have a tune that I am confident will make 700 hp with a haze and nothing more.

Good luck with your tuning! Its fun, and truly awesome to be able to use some big power without blacking out the highway behind you.

[AdamRRT]

So much of that table is under 100kPa. Am I correct that all that is wasted table? We technically should start it at 100kPa?

[FUBAR]

I rescale mine for more real world numbers. But that doesn't help much either due to the limited capabilities of our MAP sensor. But I don't need that much fuel limiting once I start seeing high boost numbers either. Basically
I've got mine setup kinda like an on / off switch.

[AdamRRT]

Care to post a screenshot or shoot me an email, FUBAR?
Hey sorry I missed your call. I was updating my iPhone software and didn't see you had called till like 12:15am. Sorry bro.

[CIDRAUGHN]

Yeah, mine is similar to Fubars, or atleast from the sounds of it. At the RPM the turbo will light, and at the boost level that will take off pretty fast, I start giving it higher fuel, and full fuel shortly thereafter. I havent rescaled it because I have found no real reason to. Like Fubar said, I dont really have a reason to control or limit fuel in a higher boost application (15-20+ psi).

On another note, I think one reason the table goes so far below atmospheric pressure could be the fact that these motors were offered in non turbo form for different applications. Without a turbo, there would be times when the MAP would read less than atmospheric pressure as the motor created a negative pressure in the intake. That's purely a guess though.

[FUBAR]

Care to post a screenshot or shoot me an email, FUBAR?
Hey sorry I missed your call. I was updating my iPhone software and didn't see you had called till like 12:15am. Sorry bro.

I would......if I could ever get back into civilization to be able to use my laptop on the Internet!!!!! ?!$&@!!!

[AdamRRT]

Take a cellphone pic and email it son! Or MMS it if you gotta.
I've never messed with that table, trying to control with the actual duration table instead. But I've decided limiters are there for a reason, and makes life easier.

[2006Cummins]

Subtracted 25% duration from 50mpa and 15mm3 on up and had just a very slight haze under mid-range/mild acceleration. Subtracted another 10% and the haze is gone, but it feels like it struggles to maintain 65-70mph, but acceleration is fine. Added 5% (-30% total) - will see what happens today. I have the boost limiter maxed out for right now, and once I get the haze under constant acceleration taken care of, I plan on taking care of the off-boost smoke with the boost limiter. The pressure table that I am using right now is just a smoothed out stock table.

Mike

[2006Cummins]

So, I'm at about -25% duration down-low, and -17% on the mid/upper-end. I also pulled a little pressure. Now, from what I can tell, I'm smoke free from idle to 3500rpm's under lite/normal acceleration. I still need to work on moderate/heavy acceleration, as well as wot. I'm happy with the progress!

Mike