I am currently looking at buying a set of test pipes for my Z and the Helix pipes seem to be the cheapest (around$175). I already have the Borla Dual Exhaust and I need to know if the test pipes will make it sound too raspy. The Borla has a nice sound but it is a little quiet for me and I would like to free up some horsepower. I dont mind if its a little loud but i dont want it to sound like a rice burner.