Hehe, this thread is old, and you guys are cute.
Compressor surge occurs on the compressor side of the turbo, but can happen for a number of reasons. One of the more notable reasons is the wrong compressor wheel in the wrong compressor housing. Another contributing cause is running too small of a turbine wheel, and trying to spool a large compressor wheel up too quickly. I can get much more technical, but I don't think this thread warrants it. In all seriousness, if you don't know what compressor surge is, you probably have not even come close to a level where you have to worry about it happening. A good majority of the turbos available on the market for DSM's are sized correctly so compressor surge is a very unlikely gremlin.
Regards,