I was told the stockers were good up to 14psi, 15 under some conditions, I had the EBC set for 12.5 peak when I first noticed the detonation (I'm reasonably sure that's what it is), so I turned off the EBC thinking that would lower it back down even more. I havn't checked the peak boost with the thing turned off yet, of course I probably wont at least for a little while since I only hit peak boost under WOT and thats when the detonation occurs.