Callaway Cars have been adding their distinctive Double-D tipped exhaust systems to custom-built Corvettes for almost 15 years. The company is now offering this exhaust to any owner of a C5 or C6 Corvette. This C5 package (PN 208.50.4800) includes polished, CNC mandrel-bent, 2.75-inch, stainless-steel tubing that flows into their signature Double-D tipped outlets. The exhaust retails for $1,095 and is delivered with instructions and parts for easy installation. One of the unique features of the Double-D is the elimination of interior exhaust resonance. Callaway engineers spent a lot of time trying to eliminate this common exhaust annoyance, and they succeeded.
We first heard this system on Callaway's Z06 development car. From the rear, the exhaust produces a hearty note, but inside the car is very quiet. Corvette Fever decided to install a Double-D on our project C5 to see if we could duplicate the same results. We wondered if Callaway Cars would be willing to part with one of their systems for this test, and, fortunately, they agreed. Next, we needed a facility to pre- and post-test our project car. We wanted to determine if we gained any power with the Double-D installation. MTI Racing in Marietta, Georgia, agreed to install and dyno test the exhaust for us. When MTI Racing owner Reese Cox called to tell us the system had arrived, we headed to Marietta.
Our '00 C5 was already equipped with an aftermarket exhaust system. We were curious if the Double-D's would provide more power. Reese put the car on his dynojet for our base run and pulled a respectable 429.1 hp and 408.4 lb-ft of torque. This was a pretty strong performance for a LS-1 equipped with a MTI Racing head and cam package. Next, we unpacked the Callaway exhaust and all of the parts were laid out, ready for installation. The car was put on the lift and MTI technicians Mike Cooper, Paul Smith Jr., and Chris Ivester began unbolting the old exhaust. This took about 15 minutes to complete. because we had to stop the team for photos, installation took a little more time . Still, everything was secured and ready for startup in about 45 minutes. Before installation, we pre-painted the optional tip surround panel. The painted panel was secured with tough double-stick tape provided by Callaway and really finished off the project. Reese inspected the finished installation and gave the team's work the thumbs up.
Back on the dyno, the car pulled 436.8 hp and 414.5 lb-ft of torque. We were pleased with the performance gain. When the car was at idle, the exhaust produced a very authoritative rumble. Next, we had to roadtest our new system. The car was very quiet inside, even when we pushed the throttle, and we did not experience any resonance inside the car. The MTI team all agreed they liked the sound this system produced compared to the former system installed on this car.
The Double-D exhaust can be purchased and installed by MTI Racing. If MTI Racing is not convenient, call Callaway Cars to get the name of your nearest authorized Callaway dealer. Overall, this installation was a homerun. our project car sounds better, has more power, and, hey, its got Double-D tips! CF