Originally Posted by GBX

Anyone have real world experience w/ sport cats in our cars. I know very few run them in favor of a bypass....but I have no desire to bypass the cat. With that being the car, is a sport cat worth the money or should I stick with my OEM cat?

Originally Posted by Modena 1

What exactly is your objective?

Sound?
Power?
Speed?
Cost?

Originally Posted by GBX

Interesting. Would have expected closer to 265 wheel with these mods.

Originally Posted by cobalt

Without doing a full header additional mods cat delete your not going to see much more than what the car has from the crank transferred to the wheels. If it was easy to get to 265 RWHP you wouldn't see any 3.8 conversions which achieve 283 RWHP.

Originally Posted by Steve Weiner-Rennsport Systems

265 WHP is achievable, however one needs different cams to do that.

Originally Posted by cobalt

The car started out with 1-2% leak down and 170-175 compression. Mods are simple cup air box, K&N filter, dansk 100 cell cat, magnaflow 3" in 3" out muffler. Installed by Protosport and tuned using a proprietary chip of their design to optimize power.

here is the dyno sheet. I also dynoed my 928 GTS the same day which was previously dynoed on a dynapac with similar results the GTS showed nearly perfect factory numbers both tests. My assumption since dynos can vary is that the GTS showed similar factory results in both instances on two different occasions I also trusted both facilities which are known for their testing, therefore I must assume these results are accurate. The car pulls very strong and currently has only 60k miles. It had 50k when this was done.

Sorry had my numbers confused earlier it was 291BHP 279 torque calculated using 15% drive train loss which is standard for these cars

I am including the GTS as well which has factory numbers of 345 BHP and 369 torque it had 50k miles during this dyno pull and is in pristine condition. The dynapac actually showed the GTS to have more but the temps weren't as hot.