MattS
May 11th, 2012, 09:04 AM
I am not sure if this should be in the e67 forum or forced induction. I put i here becuse the E67 supports 2.5 bar with out mods. I am working on a 07 monte carlo turbocharged 5.3 and an auto 4t65e trans. When the boost pressure comes up quickly at higher boost levels (above 16 psig @ 85 kPa baro) a bunch of timing is pulled around 4100-4800 rpm, just like burst knock. I have logged all the knock retards and burst knock pids when it pulls timing and it looks fine. I have been over this tune too many times to count trying to find the problem. It almost seems like the car is hitting a limint in the torque model for the tranmsission but all of the torque limits are maxed out. The problem does show up at max torque only when I am over 600 lb ft to the ground. I have attached one of the logs and the tune. Look at frame 222-292 on the log. To finish getting what i needed for turbo sizing on the dyno I just set B5157 to the timing I needed to run. Any help would be great