Dear denizens of the Forum: I've fished around in the archives for this information, but it does not seem to succumb readily to my queries. I would like to know if anyone has measured the before and after HP and torque of different exhaust system changes. Not the sounds (yes, there's the excellent sticky with the sound files, and I think they would benefit greatly from being played back on the FGT MacIntosh, rather than my Apple MacIntosh), but the numbers behind the soundtracks.
I hope some of you with the data will post the HP and torque curves or tables for your cars before you made an exhaust system change, and after, with no other simultaneous changes. Yeah you would have to be pretty mechanically anally retentive to dyno the car several times as you make changes, but I'm hoping one or more of you are kinda like me in that department.
An example of this data would be the data of a dyno run before the FRPP/Borla muffler is installed, and immediately after, on the same dyno, and preferably on the same day. Is there any performance difference? Another example would be the data from changing from stock to a header exhaust system.
Given my past experience with engines and modifications, I suspect that the performance differences are pretty small, if any, for the FRPP muffler or the X-pipe, and probably not significant even for the long header system. I suspect this because with supercharging on the intake side, the efficiency of the exhaust in extracting all burned gases is not as great as in a non-supercharged engine. However, since the long header system eliminates the cats, I would expect to see more effect on performance, but probably not a big difference.
I'd love to be proven wrong (which would give me an excuse to buy a Borla muffler or even headers), so let's collect all the data we have and publish it here for future reference.
We could also add data on other changes, such as modified tuning tables.
Torrie and GT Guys, if you're reading this message, please jump in, as your experience tuning these cars has given you a lot of insight and experience with what changes have what effects.
I will be happy to collect everyone's inputs and assemble them into some consolidated table for the moderators to post as a sticky.
Thanks in advance, Pete K
I hope some of you with the data will post the HP and torque curves or tables for your cars before you made an exhaust system change, and after, with no other simultaneous changes. Yeah you would have to be pretty mechanically anally retentive to dyno the car several times as you make changes, but I'm hoping one or more of you are kinda like me in that department.
An example of this data would be the data of a dyno run before the FRPP/Borla muffler is installed, and immediately after, on the same dyno, and preferably on the same day. Is there any performance difference? Another example would be the data from changing from stock to a header exhaust system.
Given my past experience with engines and modifications, I suspect that the performance differences are pretty small, if any, for the FRPP muffler or the X-pipe, and probably not significant even for the long header system. I suspect this because with supercharging on the intake side, the efficiency of the exhaust in extracting all burned gases is not as great as in a non-supercharged engine. However, since the long header system eliminates the cats, I would expect to see more effect on performance, but probably not a big difference.
I'd love to be proven wrong (which would give me an excuse to buy a Borla muffler or even headers), so let's collect all the data we have and publish it here for future reference.
We could also add data on other changes, such as modified tuning tables.
Torrie and GT Guys, if you're reading this message, please jump in, as your experience tuning these cars has given you a lot of insight and experience with what changes have what effects.
I will be happy to collect everyone's inputs and assemble them into some consolidated table for the moderators to post as a sticky.
Thanks in advance, Pete K