well it has both pros and cons.however dont take there to be gospel as these are my oppinion based on what i kno
if you gut the stock cat it will(obviously) give greater free flow of air as yu have removed a restriction in the system, however as the cat widen out it will cause a disruption in the air.so basicly what im trying to say is that it will work, however it will not give as good results as a de-cat that is uniform in diameter all the way through
darren