Ok, I found this post on here from a guy who dyno'd his 2001 "s".
He found a
5.3 hp gain and 2.7 torque gain.
He owns his own dyno and has great credentials. "
I am an engineer, tuner and enthusiast, and have designed parts for NSXs, S2000s, and even factory supported FWD drag race teams. My race program involved many secured world records...but I digress."
Finally: Dyno charts of de-snorked 986S!!!
Now, the dyno doesn't test the car under true driving conditions and wind speeds @ 50mph. So take the info as you want. I am still searching for the truth, as I know its out there!
Most the claims of loss of mpg came from the 987 not the 986.
exerpt "
Wow..this is so sad...so much happened on the board while I spent more time beating my poor S on the dyno today. I have repeated the results on 17...yes 17 passes with and without the "snork". The data remains the same. For what it is worth, this mod produces 4.6~5.5whp at high rpms. Whew!"
I am not trying to blindly support my decision. If i am wrong I would be the first to admit it. I just don't take some other guys response of "it felt like i loss power" as a scientific conclusion.