Tony @ MPH
February 29th, 2008, 04:49 PM
Still learning all this E38 and E67 stuff.
I am playing with/tuning our latest mule, a 2008 Z06. Was able to lean out fuel as expected and get that in line (it was seeing 10.9:1 and below at WOT from the factory... wow :Eyecrazy: ). Spark was a different issue.
I started tweaking and pushing the spark reducing tables like IAT and ECT (welcome to sunny Florida, where your timing will be about 10 degrees below what you command it if you leave those stables stock!). That offered some improvement but in many cases this car was only seeing 10-12* at WOT. Started bumping the spark high/low tables just like we do with LS1s and saw some improvement, which seemed proportionate to the amount of timing I put in those tables but stopped getting better after a certain point.
I pulled my hair out all night combing through all the spark tables, making sure knock was tuned where I wanted it to be, but could not figure out what was going on (I had the Dec E38 cals, so I also had no spark DMA pids to do troubleshooting).
At any rate, I just found the CFCO table. Hmmmm. This is new.
If I read correctly it sounds like spark will be ramped from CFCO to spark high/low upon launch (clutch pedal in and then out) and each time the pedal is pressed (between gears) spark will ramp from my higher values in hi/low to the lower values in CFCO.
Did I read that right? Is that why I could never see more than 16* or so at WOT at the track?
I hope that's it because I've never had so many fits trying to get a vehicle's timing advanced. :D
If that's not it, any tips? It is clear that aa modifier of some sort that I have not found yet is tweaking my timing down from what is commanded, and whatever it is, it's not in the spark folder in EFI because I have gone through that list at least 10 times....
Thanks for any input.
Tony
I am playing with/tuning our latest mule, a 2008 Z06. Was able to lean out fuel as expected and get that in line (it was seeing 10.9:1 and below at WOT from the factory... wow :Eyecrazy: ). Spark was a different issue.
I started tweaking and pushing the spark reducing tables like IAT and ECT (welcome to sunny Florida, where your timing will be about 10 degrees below what you command it if you leave those stables stock!). That offered some improvement but in many cases this car was only seeing 10-12* at WOT. Started bumping the spark high/low tables just like we do with LS1s and saw some improvement, which seemed proportionate to the amount of timing I put in those tables but stopped getting better after a certain point.
I pulled my hair out all night combing through all the spark tables, making sure knock was tuned where I wanted it to be, but could not figure out what was going on (I had the Dec E38 cals, so I also had no spark DMA pids to do troubleshooting).
At any rate, I just found the CFCO table. Hmmmm. This is new.
If I read correctly it sounds like spark will be ramped from CFCO to spark high/low upon launch (clutch pedal in and then out) and each time the pedal is pressed (between gears) spark will ramp from my higher values in hi/low to the lower values in CFCO.
Did I read that right? Is that why I could never see more than 16* or so at WOT at the track?
I hope that's it because I've never had so many fits trying to get a vehicle's timing advanced. :D
If that's not it, any tips? It is clear that aa modifier of some sort that I have not found yet is tweaking my timing down from what is commanded, and whatever it is, it's not in the spark folder in EFI because I have gone through that list at least 10 times....
Thanks for any input.
Tony