Stillen Exhaust with Berk HFCs

2bits

Do we know roughly how much of that 37whp was the berk, and how much was the cat-back?

370Z Engine (VQ37VHR) > 370z.com > 370z.com - Magazine

"Past the catalytic converters the exhaust merges into a single exhaust feeding to a larger transversely mounted muffler with twin outlets. As a note to tuners when we examined the car closely on a lift, we noted that the exhaust from the catalytic converters rearward is exceedingly small in diameter for an engine of this displacement and power output. It is almost as if Nissan wanted to artificially limit the power output of the engine for some reason by choking off the exhaust. We feel that a larger diameter, less restrictive exhaust may free up quite a few horsepower from the 370Z's motor."

I'm hoping that the cat-back accounts for most of your gain, since that represents a pretty easy and cheap bolt-on compared to installing hfc's and/or headers. I hear the latter is a PITA on these Z's. Awesome article, btw.