will an helix downpipe mate to an stock exhaust? and what is the outcome of doing so?

 

yes, it will mate and sound wise its only a bit louder than stock. Power wise you wont notice much gain unless you do the uppipe also.

 

then take it to the next step and tune it with cobb accessport for more power

 

are you sure a 3in to stock?

 

ummm i dont think it will.. flat flange dp to a donut flange midpipe....
UNLESS you get a shorty downpipe that takes off only one cat it could work.

 

it'll match up. Did on my car (maybe we put a gasket in there too?) Anyways, I know we put it on my car and didnt have to custom fab anything. It wont be louder really, but will rumble and "blub blub" a little more