My 991.2 S/X51 with SC and PSE is catless, and all the sounds it makes are awesome. That's the way I hear it, and that's what many others tell me. It's way more than noticeable with PSE turned on. Many Porsche folks have asked what I've done to make it sound so good, so it can't be bad.
I'm sure it would be even better with headers etc, but I'm satisfied. On a Mustang dyno pull, it measured 470 Hp, for a 20 Hp gain

 

good solid numbers there! Mustangs also usually read lower iirc

 

Thanks. That makes sense and does coincide with what we heard - 3500 rpm increase in sound (not in sport mode), louder all around with sport mode button pressed.

Sound on this exhaust is really nice. Perfect rumble at idle, aggressive when you give it the beans, quiet when going easy. My wife would never even know it's changed as she never sees >3000 rpm!

 

Yes, considering exhaust and 200 cell cat options. Imagine if my car didn't sound like my Dyson, with all that power?

 

Hi John, just curious. Is the exhaust going on closed valve by default when turning off the car?

im asking cuz when i get home i always open the valve to make it quieter but when i start the car it seems to be on closed valves most of the time which is super loud lol

I love the exhaust but it’s sometimes confusing to know when the valves are open or closed even while driving

 

The real power potential on these cars is in the headers and software. Will you gain some performance out of the rear exhaust alone? Sure, probably about 10hp but it won't light your pants on fire. Ours should give you more than most, we're the only ones that designed our system to have the exhaust with valves open flow through the primary path of the X-Pipe via full 2.5" piping out to the exhaust tips

Dyson haha, that can be fixed : ) It was great chatting with you, and I look forward to hearing your thoughts once you meet up with Varun (Large Puppy here in RL) and hear it in person!

Alright so a couple things here. Firstly, everything you're saying sound completely backwards haha. When the valves are open the exhaust is loud, when the valves are closed the exhuast is quiet. I expect this is because the valve controller key fob buttons sometimes sync wrong with the control unit, and we haven't figured out a way to reverse that yet. Just consider the buttons on the key fob a Left and Right button and determine which closes and opens the valves. Or, you can sync them to the Homelink garage door buttons and have you existing Homelink buttons control the valves. Simply open your manual and follow the instructions on setting up the buttons with a garage door opener, it's the same process : )

As for the valves themselves...they are default OPEN via spring pressure. When the valves are open vacuum has to be pulled on the valves to override that spring pressure to close them by sending a signal to a vacuum solenoid to pull vacuum on the valves (by the PSE programming or our key fob buttons if you haven't synced the signals with your homelink). When you start the car the valves will be open until vacuum is built in the system, which can happen very quickly. Now, I had a customer of mine try something once. He turned the key into the power position without starting the car, he then hit the valves closed button on the key fob/homelink, and then started the car. Apparently when the car was turned on the signal was sent to the vacuum solenoid to pull vacuum on the valves, and while the engine cranked over it built enough vacuum to close the valves by the time it was running. Therefore, he started the car with valves closed. I haven't tried this before myself, but it's something you can try and it may work

Best regards,
John Gaydos

 

Hi John, thank you very much for the clarification , yes my key fob is programmed in reverse then cuz locked button makes the exhaust loud & unlocked button makes it quiet.

I thought it was an installation error.

And thank you for explaining the valve system. I can swear I closed the valve before shutting off the car but it always started very loud as an open valve.

I will now press the button to close the valve after starting the car cuz it’s too loud in the garage. Lol