Originally Posted by icmfamous2
retarding timing I need someone to explain it.... how does it effect a tune??
You need to explain better what you're asking. If you mean retarding timing due to knock that is the ecu reducing the degree at which the spark fires in accordance to top dead center of the piston. This is done in an effort to degree potential knock. If you are seeing large values of feed back knock or fine learn knock correction your ecu is seeing (actually hearing) detonation coming from a cylinder and is pulling timing in an effort to stop it, and save your engine for going boom.
This doesn't effect the tune at all, it's part of the tune that is a fail safe for a huge variety of external stimuli that could result in knock events. The tuner has the option of setting knock protection to specific ranges of load/rpm in order to provide safe guards. A google search on this topic will yeild countless articles writen about the nature of tuning, subaru knock protection, and timing; so start reading if you'd really like to learn.