A Rennlister named Dennis sent me a PM with details on snipping the diode in the PSE relay. It was so easy!!!!!! My car sounds the way all should, and the best part,
I SWEAR IT JUST GAINED 20 HORSEPOWER! The acceleration is way better. If you have not done this, you should consider it. The silencer button still works if you need to be discreet.
Thanks Dennis!
Steve

 

More on this mod please?!

 

err how can "snipping a diode" which really makes no sense add 20hp or even more incredulously change the sound.

 

Steve was KIDDING about the horsepower increase..snipping the diode keeps the great sound of the PSE from cutting out at a certain MPH range........

 

Was it this thread from Renntech? I think you have to register on Renntech to see the thread. Looks like a simple, quick MOD.

http://www.renntech.org/forums/index.php?showtopic=2470

 

There's a speed cutout at 30 mph where the baffles close automatically so the exhaust is quiet again (noise regulation). Snipping the diode eliminates this "feature" so mode is manually operated with the switch.

The "20 hp increase" is pure sound alone. I'll give you a chance to hear PSE when I'm next in Van if you like.

 

How long did it take you to do it?

 

About 5 - 10 minutes.

 

A better approach to defeating the 25-40 mph PSE "quiet" phase is to simply disconnect the Pink/Grey wire (this is the speedometer signal wire) that goes to the relay in question. This is a safer solution than mutilating the relay.

As a side note, if you are retrofitting your 996 with PSE and install the electronics, simply do not install the PinK/Grey wire. This will disable the automatic quieting function.

 

Hi, I can always buy another relay if I need to sell it or I need more quiet. Since I did not "mutilate" the relay but merely snipped in lead to a very accessible diode. Funny though........I always assumed a more open exhaust could contribute some power increase. The acceleration from mid to higher rpms has increased=I am telling you the truth since I drove it on the same route before and after "Mod".
Steve

 

mu.ti.late |'myoötl.ät| verb [ trans. ] (usu. be mutilated) inflict a violent and disfiguring injury on : the relay was badly mutilated when the diode was cut | [as adj. ] ( mutilated) mutilated bodies. • inflict serious damage on : after the mutilation of the relay the diode was rendered useless .

DERIVATIVES mu.ti.la.tion |,myoötl'ä sh n| noun mu.ti.la.tor || noun

 

Diode snip versus cutting the Pink/Grey wire (this is the speedometer signal wire). Better? Safer?
The directions on rentech did not mention "mutilate" but I guess it is obvious why I would want to mutilate a 90k dollar car?

I think the wire snip only gains about 5 hp and the diode snip is at least a 20hp gain! bring on those Vettes!

 

Oh BTW:

Diode: An electronic device that restricts current flow chiefly to one direction.

If you did not know this I could see some apprehension in messing around with circuit boards. Identifying a wire by color and terminating it might be easier for some people. If someone had PMd me with those instructions, that is what I would have done.
Steve

 

I may be wrong, but I read somewhere that snipping the speedo signal wire affects the top operation on Cabs and cars with PCM. You can always solder the diode back on the relay or buy another relay!

 

The speedometer signal is used for several things on a 996 including the Cab top operation etc. However all of these things all have their own discrete signal line (wire) that originates at jumper plug 1/1, slot 23 on the relay support bracket. there is anywhere from 4 to 6 PK/GR lines that source their signal at 1/1, slot 23. As another example, at Jumper plug 11 at slot 28, all of the Brown ground wires go to a common chassis point there.

While altering the relay circuit by cutting the diode will certainly disable the speedometer signal from engaging the PSE vacuum switch (which closes the muffler baffles), removing the signal by removing the source line (PK/GR wire) is a more proper way to do this. Simply pull the PK/GR line that goes from the PSE relay to Jumper Plug 1/1.