I just made a DIY video for the TS Pro 1 Secondary Cat Bypass Pipes. Same process and directions for Fabspeed and NHP secondary cat bypass pipes. All of them claim 7-8whp and 25 lbs. of weight savings.
I got a mechanic to torch off the 14 melted and rusted bolts for $50, then I drove it home and did the install. Even with the bolts cut off, everything was still stuck together so a hammer was needed to loosen everything.
I did the install in the cold rain because I couldn't wait. It took me just over 1 hour. When I finally test drove the car this morning on my way to work, it was SNOWING. It snowed for 20 minutes, then rained for the rest of my commute so I did not get to test out the acceleration increase yet. But the sound was definitely noticeable.
I just went out to record the exhaust sound in a parking garage to avoid the rain.
Porsche Boxster 986 Test Pipes DIY - YouTube