I have been working on a good smokeless tune for a while now, and have made some progress, but am still not happy with the results. On my latest tune I have reduced the commanded mm3 in the lower rpm's, reduced the main duration table by 10%, reduced the pilot table by 10%, eliminated post injection, reduced pressure by 3%, set timing at 50%, and regulated the boost limiter out to 17psig. At this point I still have what I call the "pigpen effect" (like the kid with the cloud of dust following him on charley brown). This is even during moderate acceleration, or high rpm and low load.

I can make the truck not smoke to some degree, but it cant get out of it's own way until it builds a fair amount of boost - then it goes ok, but still smokes some. Or, I can make it decent to drive, but then I get the pigpen effect. I have gone as far as reducing main duration 35%, pilot duration 15%, pressure 10%, reduced commanded mm3 quit a bit in the low/mid rpm's, and adjusted the boost limiter to make it driveable. I have tried running more pressure and less duration, less pressure and more duration, less pressure and duration, more and less timing, more and less pilot duration, tweaking the boost limiter, etc. Admittedly, the boost limiter is the only limiter I am using. The reason for this is that I have found some of the limiters to have little/no effect, and it is easier to keep track of what just the boost limiter is doing, as opposed to try to figure out what each limiter is trying to do at what point.

What I would like to do is to use the boost limiter, or whatever, to limit acceleration smoke, but still be able to "get some" right when I floor it.

Thinking back, when running just the bully dog tuner (with injectors) - on any setting, I would have some acceleration smoke. With the quadzilla pressure box installed it would really clean up the acceleration smoke - to almost clean on moderate accel, and the truck would be more responsive. This makes me wonder exactly what the pressure box was doing. I know that pressure boxes obviously add pressure - which I have tried, but also act as a "boost builder" and keep from setting an over boost code. If it is adding more pressure (fuel quantity), and allowing a little more fuel earlier (more fuel), then I would think that it would smoke more - not less. The box must scale the amount of pressure to boost in a way that I am not seeing how to do using efilive.

Anyone have any thoughts on this?

Mike