Background: Silverado SS, 799 heads with light port work, 226/229 573/582 112lsa, br7ef plugs gapped at .035.
So i finished the install got the truck running and started tuning. I followed the idle tuning for cam here: http://www.silveradoss.com/forums/to...sing-hptuners/
Since i didn't have it all done to go till 2am i left LTFT on so i could have a safer drive to work. Shut them off on the way home to log. MAP was unplugged so i didn't have any usable histograms. From there got a few logs, and used the AFR error % to start dialing in VE.
Then i let it cool down and went back out 3 hours later and its about 26* out. It cranks and started then stalled when i put it in reverse. Now nothing!!!!
Attached is the last running tune. I do not have any logs. Also attached are some mods i made to try and get it starting. Never had to tune for cold weather, the only other GM tuning i've done was on a roadster so it only saw warm weather.
I tried adjusting Cranking VE up then down unsure of which to do, then did some quick reading and saw that cold weather causes engines to run rich since the air is more condensed. So i reduced VE. From there i increased Cranking Timing 3*. Then lastly i increased Start up Airflow by .265 to .794 below 68*
One thought is the BR7EF plugs are not good for this cold. When i started the truck last night it had been sitting in the garage with a heater infront, then this morning we had some warmer weather and it was above freezing.
Silverado SS Idle and VE tuning 3215_Last running.hptSilverado SS Idle and VE tuning 3215_Cold start mods.hpt