I now know why the LS1 guys can get email tunes so easily compared to the old mail order OBDI stuff. The new stuff just works that much better. I swapped from a very mild LT4 cam to a Comp custom grind 206/210* cam on a 110* LSA and didn't touch a thing on the tune, twisted the key. it fired right up as I pedaled it lightly until it hit closed loop and quiclkly started to learn fuel trims. I unplugged the MAF, ran my 33 miles to work. I used the HP Tuners program and my Excel spread sheet to adjust the VE tables, reflashed the ECM. Repeated this procedure about 3 more times. Hooked the MAF sensor back up. Rescaled my MAF tables from long term fuel trims. My LM1 wideband now says that I am dead on my AFR targets of 12.6:1. Running nearly a full point leaner than stock, I had to tweak the spark tables to eliminate some mild knock retard I was seeing on 87 octane running with a 195*F thermostat. I have since disabled the P0128 code and returned to my 180*F thermostat. I bumped the timing back up to 28* from 24* after filling the tank with premium a couple of times. On the dyno I was only able to find 7 RWHP and 12 ft/lbs of torque more than my datalog tuning. I find it very comforting to know that had I not hit the dyno, I would have been within 2-3% of my maximum power potential. I think a few more tweaks on 93 octane gasoline with a 180*F thermostat will crest 300 RWHP. I know it will make over 300 RWHP after my Doug Thorley Tri-Ys go on.
https://www.youtube.com/watch?v=hbIKimA_0i4
https://www.youtube.com/watch?v=qyiJPB4HcXc
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