I have looked and looked and looked but cannot seem to find much info on this?
Does anyone with ACTUAL experience know what kind of timing curve these RATS like?
When tuning all my LSXs I would run 22+ degrees, sometimes up to 28*, as long as I wasnt seeing any decrease in power or any knock retard. This isnt an LS1/LS2/LS3, so I am kind of out of my element here.
What about AFR curve? I used to richen up just a little at peak torque, so if I was running, say 13 AFR flat across all RPMS, I would set it to be richer at like 4500 RPM, by a small amount. Like 12.75 or so. Then smooth that in. BUT! BUT: this engine makes peak torque wayyyy down low, so I am wondering if I should follow the same principal, richen it up a tad down low, and lean it out up top slightly? Right now it is set to 12.76 AFR across the board until I get the timing thing worked out.
Back to the spark: I noticed that I did have to tweak a few modifier/adder/correction tables to even get the 15* from the stock timing advance tables....I was just looking at my last log, and I had a momentary dip down to 9* at WOT @3000 RPM..? Im digging around trying to figure out why. ECT wasnt high, IAT wasnt really high. I have YET to see any KR logged in any of my 15 or so runs.
The IAT Spark Advance Correction table is set to pull quite a bit of timing with IATs relatively low, so I got rid of most of the IAT Correction below 130* IAT temps. That seems to allow me to get the timing I wanted to command at the Main Spark Advance table. The ECT Spark Advance Correction table is set to pull 1-2* when it hits 212-221*..I left those alone(Im usually around 19x* ECT) and will opt for a lower temperature thermostat (180* probably)to keep it from hitting those cells for sure. Hopefully it will bring down my IATs a tad as well. I will be installing that thermostat later on today after I finish putting the rear end back together lol...been waiting for my shiny new rear diff. cover & gasket to come in.
In the future, I do plan on moving the air intake/filter etc in an attempt to lower IATs. I will likely get with something NOT metal so it will help insulate the heat from the incoming air.
So what say you?
#1 what timing curves have you have experience with?
#2 did you have to change anything else to realize the full timing in the High/Low octane tables?
#3 how did you set up your PE EQ Ratio table?
Thanks guys. I am open to criticism!
attached is my base tune, set up for Open Loop/SD until I dial in the VE and timing all the way.
2001 Silverado 2500 HD 8.1L - Stage 4 Tune - SD Tuning Mode Setup - 12th.hpt