I havent had any knock problems that i'm aware of but I've only looked on the controller twice since i've had it, I live 5-6 hours from a tuner and work a 7 day roster so I havent had it tuned since i've had it but it feels like it is straining at the moment when I start to get above 5500rpms so I've been cautious over the last couple of months. I would appreciate any info on checking psi as the turbo set up is pretty new to me. I didnt start it for about 6 months straight and the battery was so flat it was thrown out, I am also wondering whether it is possible in a case like mine that the memory battery in the apex ecu could restore to default if no power was run through it for a long period of time like that.