With one over-axle pipe slipped into a muffler, the first muffler-pipe assembly can hang in place without tightening its clamp at all; time to put in the other side! An assistant will be useful here to help guide the over-axle pipe in without disturbing any of the electrical and other connections overhead. It'll be important to adjust the positioning of these pipes before final tightening such that adequate space is kept between the exhaust and all other parts of the car (particularly meltable ones). | 
The Corsa Xo-pipe (XO stands for "crossover") is now slipped onto the front of the over-axle pipes. This step will definitely take an assistant (and probably a transmission jack too), as getting both over-axle pipes to slide completely into the XO-pipe can be tricky. Use the trans jack to hold the XO-pipe nearly level, and with the assistant simultaneously pushing the over-axle pipes forward and keeping them aligned, hit the front of the XO-pipe with a mallet and wooden board. Have the assistant watch and tell you when they're in all the way. | 
With its front portion loosely connected to the cat pipes, the rear of the XO-pipe attaches to the stock GM springy hangars at the front of the transmission. Compare this photo to the one of the stock system, and you'll see how CORSA's larger 3-inch tubing more fully occupies the tunnel, yet is tucked up just as high and doesn't even come close to interfering with anything. CORSA's engineers did their homework, and it sure helps that this space was designed with the Z06's factory 3-inch tubing in mind! |
Now adjust all pipes before tightening any clamps, being especially wary of the angle and position of the over-axle pipes (once again, there are small hoses and electrical plugs up there). To tighten the clamps where the over-axle pipes meet the mufflers, you'll need to snake a long extension through the Corvette's aluminum subframe. Note that these mufflers are canted upward toward the front, which helps straighten the exhaust path. | 
With everything else tight, secure the nuts at the rear of the cat pipes. You can see here how the Corsa system adapts to the stock 2.5-inch pipes, yet immediately opens up to its full size before flowing into the "X." A little birdie told me Gmhtp might be installing a set of long-tube headers with 3-inch collectors in the near future; we expect this Corsa system to adapt easily to them. | 
We're almost done! Start the car up, then raise it while it's running to check for any exhaust leaks; retighten all clamps as necessary (band-style clamps need a lot of torque to seal). Aside from the stainless steel construction and 3-inch tubing size, the most visible difference underneath the car is CORSA's XO-pipe, which stands in contrast to the factory's H-pipe design. CORSA says this style of pipe helps balance exhaust flow side-to-side and reduces exhaust popping on deceleration, thereby improving both sound and power. |
Whether you prefer four or just two, you'll have to agree Corsa's 4-inch Pro-Series tips add a bunch of style without being gaudy-and the shiny mufflers look good too. As to the sound, we were delighted to find a deep rumble that becomes very sophisticated under power, yet is not intrusively loud. And as promised, Corsa's system showed no sign of interior resonance at highway cruise, with the only hiccup in sound quality being a slight drone at idle (presumably due to the cavernous size of the 3-inch pipes; we'll bet this goes away after we install a set of long-tube headers). | 
East Coast Supercharging's outdoor Dynojet was the chosen site of our dynamometer testing. Located in central New Jersey, these guys work almost exclusively with Corvettes and cater to customers from around the country, from builds mild to wild. They hold and continually break their own records for the world's fastest supercharged C5, among other accomplishments. | 
When the smoke cleared, the Corsa exhaust showed its worth: a gain of 13.2 horses and 9.2 lb-ft at the tires, bringing grand totals to 359.3 and 350.5, respectively. That's one heck of a gain for a cat-back exhaust, and with its virtually limitless flow capability, the Corsa system will prove quite an asset as our future engine mods help us gain more and more ground on the Z06! |