Throttle lag during quick WOT upshifts, Stage 4 Cam NA C6 Z06
Hi fellow tuners,
I'm experiencing serious throttle lag during quick WOT upshifts on a 2007 NA Heads Cam C6 Z06. The C6 Z06 runs flawless except for this issue. I've tuned dozens of C6 setups (including another Heads Cam 2008 C6Z which didn't have this issue) and I've only experienced this throttle lag issue twice, the previously being a big cam NA 2008 C6 LS3 manual which was a failed attempt in solving it, but I would like to solve it for this C6Z. Looking for advice on other experienced tuners that have hit a wall with this issue on similar setups and have found solutions, before I start playing with TQ management settings. Latest tune attached, along with a stock same year reference tune.
Is there a particular time in the log that was the most prevalent? Looking at the couple WOT-shift-WOT spots I saw it looks like the TPS is following the accel pedal, and spark is not dipping at throttle re-apply. If the pedal and spark are actually behaving like they should (and appear to be unless I'm missing other points) then the only one I'm not clear on is fueling. Is the Wideband signal an actual serial measurement? Looking at the spike where EQ commanded goes from .84 back to 1.0 during the shift and comparing to the sensor? reading there is a bit of a delay before the fuel gets to the sensor again at WOT apply. This delay is all relative though, maybe just the time it takes for the combustion to reach the sensor, but wondering if maybe clutch fuel cutoff is active? and maybe letting the intake runners, valve, etc all evaporate dry and requiring a bigger transient shot of fuel to re-wet?
My apologies, the log provided doesn't probably show the issue (i was driving, final pulls, not really pushing for fast shifts). The issue was noted by customer aftwerwards when really pushing some quick shifts at WOT. I'll try to provide a fresh log showing issue once I get vehicle back today to troubleshoot. I wanted some experienced tuners with Heads Cam NA C6Z's to chime in on TQ management settings and/or TB settings if possible.
Note: Driveability and everything else i got it on point.
Will be key to see if it is pulling throttle blade position or pulling timing. If it's pulling timing, then check if the TQmgmt spark channel is showing a retard amount which will confirm if it is TQ management or not - as a starting point.
Closing out this topic. Lag was found to be a combination of driving technique by customer and a few throttle based TM settings that were still enabled.
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