[r33_RGSport]

@gotstocks , thank you for the mention.

mach250 , full exhaust system will not give you much gain by itself.
But, with a tune and catless downpipe, you will wake up the beast.
Dinan is one of the good brand, most don't like it due to mild tune at premium price.
While RaceChip, is a cheaper product and have similar or more power gain.
I've got a few customers, not G30 in particular, that switched from Dinan to RaceChip.

But regardless the tune, catless downpipe itself will give you a good gain.
Just be aware of the CEL.
There are solutions out there, just can't mention about it. EPA, DOT, and CARB been actively cracking down on it.