Just wanted to know what purpose this serves. I mean if the car is tuned and it runs good why would you even need to retard the timing under boost? I have been running my setup for about a year and have had no detonation problems and my timing is set to stock. Any answers or opinions would be great.

 

you pretty much just answered your own question but retarding timing is to avoid detonation

 

Some engines can run stock timing and still not detonate under boost. I belive that if your setup is properly intercooled and you run proper octane fuel and proper heat range plugs you may not have to retard timing at all. It all depends on the engine really. Some you can get away with it, others you can't. Generally FI that's not intercooled is where you want to implement retarded timing....... generally.