Tried disabling M6 spark smoothing, forcing it open loop rich and lean, added and took timing out nothing seems to really affect it. zerod out all the throttle crackers and followers to see if airflow from there was contributing to it, nothing seemed to change it

Any other ideas? Its a 427, with an unknown cam, and a no name throttle body. Before straightening out other stuff on tune cust said he doesnt remember it bucking that bad, but flash the original program in it still does it

Timing real jerking when it starts doing it (timing from where frame 310) but when I held timing constant with controls it was way worse (locked timing log)

Only other thing Im thinking is SD, if maf reading is erratic enough to do that, but the gms/cyl value isn moving around mor ethan .02 which wouldnt make it read in wildly different areas of timing table. Maybe burst knock pulling it out when it does that

Files/logs posted on http://www.hptuners.com/forum/showth...187#post398187

 

I'm no tuning expert, but that's how my car acted with a broken injector o ring causing a vacuum leak.