SD2 tuning

[good2win22]

So I'm a bit confused but that's not hard to do.  Apparently there are 4 different ways to to get a target air fuel ratio at idle on parameter 2.


Set to 9.7 to turn on closed loop and use a target a/f from the PL AFR table.
Set to 9.8 to turn off closed loop, but still use a target a/f from the PL AFR table.
Set to 9.9 to turn off closed loop, and use a target a/f preset in the chip.
Set to 10.0 and higher and this will be your target a/f.


Which is preferred/best method?  I noticed on the PL screen that when the chip was installed it was set at 98 but there was no AFR correction data when the engine was running. I then changed it to 13.5 and I got an AFR correction data.

[Steve Wood]

I don't think there is a preferred or best...but, I would start off with the last option and set it about 13.5 and see if it idled smoothly in gear at that point

[good2win22]

It's set at 13.5 now.  Idle is smooth. Doesn't die or stumble in gear.  I did adjust the injector offset to get the a/f correction closer to 0. Went for a little drive and there is a lean spike when accelerating.  Guess I'll work that parameter and the cruise parameter next. 


If what I understand is true, then the 97 means I would adjust the a/f correction via the VE table with the help of the sensor information feeding their data back to the ECM and the 98 would not show an a/f correction because it doesn't care what the sensor info is. 

[good2win22]

I think I have a little better understanding now.  Adjust the parameters in the blm grid and the chip adjusts the tables. And if you're feeling froggy, you can go into the tables and adjust as you see fit.


I can easily see how you could completely destroy an engine without any idea of knowing what you're doing. Lots of options does get overwhelming at times.


Now I need to understand how each parameter interacts with the other.  Also it would be nice to have a second person to enter info while driving.  I do like the ability to see results instantaneousl y.

[Steve Wood]

I did not upgrade from 1 to 2 when Eric asked me if I wanted to.  I don't seem to want to focus on one thing anymore, but, that is my understanding  as to how it works.

It should be pretty close on the defaults and I would not make radical changes.  At the 10.0 sec range, I don't really think it will be any faster than a well tuned regular chip no matter what the xfi shills claim...On the other hand, it's fun and the not too expensive

[good2win22]

Drove the car to the UTI block party up north of Dallas yesterday.  Went up and back and a trip over to Kellers drive in. A little over 300 miles total. A few observations:


Letting the presets in the chip handle the cruise fuel makes for a really steady wideband and narrow band reading. However, a/f correction still wants to pull fuel and the black on the end of the exhaust confirm the richness.   Not exactly certian how to address this for cruise unless I go into the tables. Don't think I'm ready for that just yet.

[TexasT]

Back the fuel pressure down a bit maybe? Just have to remember to crank it back up when you need it.

[Scoobum]

Jason, I'm no help with this...but I'm curious what the AF reading is at cruise.

[nocooler]

Think of it like an excel spread sheet
RPM on one axis and vacuum/pressure on the other. The cells are fueling.
The AFR and NB is going to be consistent as you are sitting in one or 2 cells for cruise. As the rpm and pressure is are staying steady.

[larrym]

Keep posting Jason I'm really leaning this way.


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[good2win22]

Rich,
The fuel pressure needs to remain set at 43. If not then the tables won't work as their supposed to and the correction will be more or less at any given condition. I believe that this is why setting up the warmed up idle is so important. Once the corrections are made at idle, the rest of the tables will reflect those settings except at WOT. There you have to be on top of the game or damage will occur


Brad,
With the cruise fuel parameter set at 97, this lets the chip decide the AFR. This is something I don't have a good grasp on. I don't understand exactly what variable, IAT, tps, map, speed or combination of them, decide what AFR to pick.  Cruising last nightbetweeen 65-75, the target AFR would go from 13.7 to 14.5 depending on where the pedal was at, i.e.  Going down a hill, go up a hill and on level ground. I can input a target AFR of say 14.5 for cruise fuel but then the chip tries to make that the target AFR at all cruise conditions which may not be ideal.


As far as I can tell, there is no learning mode in the chip.  You are the educator.  Sticking with the defaults may be the best bet after getting the idle correct.


I can say this, drivability is much much better with this chip than it was on the 5.7 with my engine combo. 

[Scoobum]

I'm at the bottom of my game...so this ain't the chip for me.

[larrym]

Isn't load one of the parameters that is used to calculate fueling


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[larrym]

Load is calculated by MAP and RPM in SD and maf and rpm in stock set ups?


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[Steve Wood]

Yep