I just had the Akrapovic mid-section (X-pipe and high-flow cats) installed with the stock rear section. EF1 Motorsports in Signal Hill, CA, did the install, with Chasen from Dynotech handling the dyno pulls before and after. [Thanks, guys!]
I didn't get the image from the "After" dyno runs, yet, so I apologize for the minor tease. I will post those as soon as I receive them. Experts feel free to chime in about the "Before" traces.
UPDATE: I've added the "After" dyno runs and the comparison plot. The modification netted me 14.5 HP and 12.1 lb-ft of torque.
I'm still deciding on what rear section to get, so the car has not been tuned to fully take advantage of the new installation.
The car now has a racier (not ricey-er) sound at higher throttle openings, but there is no drone that I can hear at any RPM or throttle opening. It just sounds a little more aggressive overall, both inside and out. My memory of the full Akra system was of a quieter sound than this setup overall, which is a bit of a surprise. Anyone out there have just the Akra axle-back that thinks it is
quieter than stock?