I finally got around to getting my 2bular exhaust system installed on my Evora. I decided to have VSA Motorsports do the install, rather than do it myself. They have done the installs before, and know the routine, so they could do in a couple days what would take me a week. Thanks to Alan, Sergio, and Stephan for their expertise, and attention to detail !
Aside from some minor adjusting, the system install was straight forward, but time consuming. It took 2 full days, start to finish. Extending the O2 sensor harnesses was easy, but took a long time to figure out the routing and required lengths. The 2 Post Cat sensors, which had to be extended, were lengthened about 3-4 feet, to allow a neat routing along the rear sub frame. They were mounted using adel clamps, screwed into rivnuts placed in holes that were already in the sub frame. See Photos.
The weight difference between the Stock Manifolds-Downtube- Cat and Stock Muffler to the 2bular Headers-Downtube-Metallic Cat and Lotus Sport Muffler was 19.74 lbs., of which 13.5 lbs was the difference in the mufflers.
The sound of the 2bular system and Lotus Sport Muffler is amazing ! It has a soft rumble at idle, and has a full, but not excessively loud tone on easy acceleration. The more throttle you give it, the more robust it gets, and under full acceleration it sounds serious. The good news is that cruising at 70-75 MPH in 5th or 6th gear, at 2,500 RPM, you can barely hear the exhaust note. It is definitely not objectionable for conversation or listening to the radio. However, as soon as you accelerate at all, or load it going up a hill using more throttle, the sound picks up.
I did Dyno runs with the completely stock exhaust just before the install, and will repeat them on the same Dyno with the new exhaust system after a few hundred miles to allow the ECU to adjust. The good news is that it NEVER threw a CEL after the installation. I'll post the before and after Dyno results here, after I get them.