How does the PSE work, I read there is a switch to by pass the cats? If so this should give HP Gain, and no need for Hi Cell Cats? Any help appreciated.

 

PSE is mufflers not cats...no cat bypass.

 

There is a switch that activates the PSE making it louder. No power increase is acheived, just sound.

 

I have the PSE with the Sport Chrono when I turn it on not only does it sound great it becomes more aggresive at the beginning of every gear.it's a great combo.I don't know if it adds HP I would love to see a dyno with and with out.

 

It changes the mapping of the accelerator. It's not adding power, just makes the gas more aggressive. I'm interested to see a diagram of how the PSE works, though. Does anyone have such a thing?

 

Actually I believe the Sport Chrono changes the mapping and the PSE is just tied into that setup. So adding a PSE to a non-Sport Chrono equipped car wouldn't give you lovely throttle response...

 

Carl11 ,

I have the diagram, but it wont tell you anything.
(Just a wiring diagram with numbers on the wires )

But I can tell you how it works

1.The 911 mufflers ( all of them ) have three chambers in them.
In the standard mufflers, the exhaust gases go through
ALL three chambers before exiting .

2.The inlet pipe ( see a in diagram below ) goes thru chambers 2 & 3 into chamber 1.

3.The exhaust pipe starts in chamber three ,goes thru chamber 2 and then exits
( b in diagram )

4.There is a pipe stub which goes from chamber 1, thru chamber 3 into chamber 2 .
(you can't see the stub, because it's behind the muffler cover in the diagram )

Anyway, the exhaust gases go thru this pipe from chamber 1 into chamber 2
and from there they seep into chamber 3 and then exit thru the exhaust pipe.
(a little exhaust also seeps from 1 directly into 3 thru a couple of small holes)

5. PSE :
In the PSE , the exhaust pipe stub ( see #4 above ) which comes from chamber 1 ,
thru 3 into 2, instead of ending in chamber 2, now continues out of the muffler at point c .

This pipe now has a large hole in it ( in chamber 2 ) to allow the gases into chamber 2
and then seep into 3 , as they do during normal operation , if the PSE valves are closed .

The pipe also has a vacuum controlled valve in it (outside of the muffler ).
When the PSE is on (LOUD )the valves open and the exhaust exits already
from the first chamber (that's why its loud )

6. OK, now for the controls :

The PSE is controlled by the cars computer .
If the car has Sports Chrono , it activates in Sport mode only .
If not, there is a separate switch ( with the dual exhaust symbol on it )
which activates the PSE .

Per factory setting , if activated (loud) the PSE exhaust valves
automatically close ( quiet ) whenever the throttle is used aggressively
at speeds up to ~ 50 mph . As soon as you back off the accellerator,
they open again . Above that, they stay open ( loud) ,regardles.
(that's to comply with noise emission standards in certain countries )

The PSE valves in the exhaust pipes are operated by the cars vacuum system .
(They are normally OPEN and are CLOSED by the vacuum )

A 12 Volt solenoid valve ,located in the engine compartment ,
controls the vacuum to the valves. The solenoid is normally CLOSED
and OPENS when it gets 12 Volt power
( the cars computer controls the electrical signal )

When the solenoid valve OPENS, it allows the cars vacuum to CLOSE the PSE valves .
when it gets no power, it CLOSES ,there is no vacuum to the PSE valves and they stay
OPEN ( loud )

That's why one of the easy "always on " solutions is to simply disconnect the
12 V power wire to the solenoid, and the PSE is always loud
( that's the orange plug in the engine compartment )

So, if you want bypass the factory auto. cutout ( at speeds up the 50 mph )
or, if you want to have the PSE on loud, without going into sport mode,
all you need do is to splice an on-off switch into the 12 V wire going to the solenoid .
( I put mine into the ashtray )
When the switch is open, no 12 V power to solenoid, PSE is always loud.
When the switch is closed, the solenoid works as designed by the factory .

Simple . Lol

One more thing ,regarding power gains
( and I hope this disproves some of the "dyno proven" ,ridiculous power gain claims
we get from some of the aftermarket muffler peddlers)

When the PSE bypass valves are open , the OTHER , pipe is still open as well.

The exhaust gases will take the path of least resistance and most of the gas
will exit already from chamber 1 , they now have ~ 2/3 less muffler to go thru
and have TWO pipes to exit thru instead of just one.

It's therefore not unreasonable to assume that that there should be less
resistance thru the system.
If ANY muffler should produce measureable power gains, it should be the PSE .
Despite this, Porsche makes no gain claims .
Simply put, there just aint that much to be gained from a muffler. PERIOD.

Get whatever mufflers you like, but get them only for the sound.
Forget all the BS about power gains on a Porsche engine.


hope this answers your question .

 

Very impresive piece of info, JCS. Now I know it's worth the $2400 option and here I thought it was just muffler that can be turned on or off and SS tailpipes.

 

hey guys i might be selling my pse, i have a fabspeed and pse set and so far i am leaning towards the fabspeed but will decide once i install them.
either way one of them will be for sale by the end of the week, both sets include tips.

 

Thanks so much, that was impressive!

 

Did you patch a switch into the solenoid at the orange switch in the engine compartment or did you attack it under the rear passenger carpet? If so, does that red/purple wire ( +12v )wire have anything to do with the mapping?

 

I removed the rear carpet and electronics metal cover (passenger side)
and cut the red/purple wire before it exits into the engine compartment .
Then I ran the 2 wires behind the passenger side exterior trim panels to the front and then into the console.

The red/purple wire has nothing to do with the mapping .
It is only the + 12 V power going to the solenoid .
Putting a switch into it is the same as just disconnecting the orange plug.

 

thanks for the info JCS