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9.5 Knock at 40% throttle when vehicle is shifting from 2 to 3 gear

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Hi how are you guys? I hope you guys can help me, I been having this issue where my car is having a terrible knock at mid throttle (40%) and I just notice that is happening when vehicle is shifting from 2 to 3 gear with light engine load (40%) around 2300 to 3000 Rpm. I'm pretty happy how the car runs at WOT and below that that 40% Throttle I mentioned before. I have been data logging and sending this logs to my tuner that so far has been amazing, but we haven't figurate out this issue. Car is a 2008 Pontiac G8 GT fully ls2 short block build (forge pistons, forge rods, arp bolts.) Lsa supercharger 2.4 pulley 1050cc injectors, 4.5inch intake tube and ls7 style MAF sensor. Thanks in advance. I attached the data log in case u guys can see it

Attached Files

Is it a momentary knock that disappears almost at once, or continue for a second or two?

Have you tried reducing the timing at the rpm range it was shifting into?

Have you checked the manifold pressure/vacuum reference line is unkinked, and stiff enough to avoid closing up under vacuum?

I apologize in advance as I haven't opened the log file, but what kind of transmission is it? Particularly if it is a automatic transmission that uses a large ignition retard or cut, you can get a spike in knock readings on shift events due to the rapid change in cylinder pressure.

Hey gord: This knock comes ones and start decreasing, and the map is located on top of the supercharger lid, so I don't think is that. Yes, I really think that is too much timing in the tune at shifting

Hey n8b: The transmission is automatic and is call 6L80. Yeah, for sure the vehicle controls the shifting torque points by timing but my question is: This timing is just by the Ecm or the transmission has a separated table timing that has to be adjusted?

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