Have a new '11 Mustang 3.7, and put a BAMA 87 performance tune in it this past Monday. Drove it for a couple days and noticed some knock in the 5500-7000 rpm range. I contacted BAMA and they sent a revised tune, and I data logged the new one. I got a knock retard spike of -4.99 a couple times. So the sent me a new tune again that I have not logged yet. What I am wondering is have I damaged the motor from a few days of driving it with knock happening? This has me pretty worried. I called my Ford dealer saying I must have gotten bad gas and its knocking in the upper rpm's and they said basically dont worry about it.