"Today I pushed it again and now it seems to make a wierd noise exactly at about 5500RPM. Seems to be coming from the drivers side, I think. It sounds a bit like when you let the air out a balloon when your squeezing the hole bit with your fingers, and only starts at about 5500RPM and get louder as the revs rise"
thats the strangest explanation detonation Ive ever heard
what was the knock reading?
either that or your getting some comp surge ?