Track Times Took A Hit!

[slowfive0]

Not off topic at all. Discussion and learning for all hopefully. Krambo or some of the others could explain it much better then me, but basically what I did was map my run from the time I went 100% open on the throttle until I closed it. In between those points, I would look at the spark map ---- rpm point vs. the cyl air mass (basically the air the engine is ingesting) and evaluate the timing at every one of those points. The latter points of the chart where the blower is going full tilt and rpm is climbing is pretty easy, but the other points were more challenging as they populate different cells all over the map.

 

Ideally, if you could sit on a dyno and run the engine to XXX rpms and hold it there at different loads and add/remove timing to maximize power in those given cells, then move on to next cell, etc, would be ideal. AWD introduces some problems with that-lol!

 

Just try to start with a good map and make sure you're not knocking all over the place. Make sure your fueling is right (not just WOT). In general, make sure your tune is pretty much cleaned up. Also, make sure your timing map doesn't have big gaps; i.e. going from 16 - 25 in the next cell. Try to keep everything gradual. The smoothing feature helps a lot here. Once you have a nice timing map (and tune is safe---no Knocking) as a base, take it to the track or a desolate area and make some hits in at least 2nd if not 3rd and start to tweak your table. Don't add more then 2 degrees at a time. Don't make too many changes at one time, then go retest. Look at your mph increase or decrease and see if your changes helped. If they did try another degree or two. Do this until you see no more increase in mph gain or you see knock. Usually, you'll find a sweet spot and you want to back off a couple degrees before that. Basically, where you seen best performance and not any further above that. Once you get the upper ranges of your map dialed in closer, start to work on other areas like where your launching at and the transition from that part of the map down into the heavy load areas near the bottom. The logging software is your friend and makes it pretty easy to isolate what cell is being utilized. You will have to modify multiple cells at times as the rpm or load value will be in between two cells. In those cases, the computer is just averaging between cells. On the street, I will make a small hit (say a dead stop to just past the 3rd gear shift) and look at the time at the bottom of log file. I'll take that time and compare it the next log (after making another change) and see if it improved or not. Works pretty well. Not very hard because I'm awd. If I was dealing with tire spin, I would probably just get going at XX mph and then wack it. Whatever you do, just be consistent and make small changes. Best to make one change at a time and evaluate your results.

 

I'll be glad to help you out where I can. I'm still have a ton to learn as well. My fuel trims are off around 5-7% and I would like to get them closer to 2-3% but that is another day....lol

 

Your truck is going to rip when you get it dialed in.

 

I wont get your post off topic, but we need to hit the track.

But where you said you did the off idle spots to WOT? Idle good, WOT good, in between not so good

I am watching the weather.

Edited September 26, 2011 by slowfive0 (see edit history)