Let's not kid ourselves, there's truly nothing like the sweet rhapsody of eight cylinders as you're rowing through the gears. And when it comes to the C5 Z06, we'll be the first to say that The General did a remarkable job with the factory pipes. Especially when you take into consideration that this was the first production exhaust to feature titanium construction. If you didn't already know, this was part of the Z06's weight reduction program. The tone is bit throatier over the standard C5, but after a bit more seat time, we started craving a system that would kick up the decibel factor slightly, better representing the stout LS6 powerplant.
In deciding on what setup to go with, it came down to several factors. We contemplated a complete exhaust system, beginning with a set of long-tube headers for all out performance; however, reality kicked in and directed us to a package that that would still allow us to pass our stringent California smog emissions. The only viable option was to upgrade to an axle-back system, keeping the factory catalytic converters in place.
As mentioned earlier, we knew we wanted something to tickle our ears, but we certainly wanted to avoid upsetting our neighbors during the occasional early morning commute. Above all, we also wanted to stay clear of any unwarranted drone. If you're not familiar with this, it's when the exhaust frequency is constant at a certain rpm; this can get a tad annoying on long drives and makes it difficult to interact with passengers.
The exhaust system that addressed all of our concerns was Granatelli Motor Sports (GMS) LS6 axle-back exhaust system. This system features a complete T-304 stainless steel construction, a straight-through muffler design for maximum flow, and quickly bolts on with minimal effort. Net gains to the rear wheels were very respectable and showed immediately on the chassis dyno, but you're going to have to read on to see those numbers. When it came to road testing, we took a 600-plus-mile round trip up to NorCal and came back with one simple verdict: we have a winner.
What We Did
Swapped out the factory exhaust for a Granatelli Motor Sports axle-back system
Gained performance and a sweet sound