987.2 Exhaust hack - possible?
12-08-2019, 11:22 PM
#17
Rennlist Member
Do the headers, 200 cell cats and Carnewal cams simultaneously—just take time, use plenty of PB blaster and have replacement gaskets and replacement hardware. With patience. Decent mid lift and tools with an extra set of helping hands in a warm garage, competent DIY in a long afternoon. Don’t tighten anything to torque until your’re aok with the alignment of all,
then start at
headers and move rearward.
then start at
headers and move rearward.
12-09-2019, 01:19 AM
#18
Here you can see it pretty well.
Look at the round welding on the upper part where each side of the exhaust has a funnel shape.
https://rennlist.com/forums/parts-ma...an-1050-a.html
Look at the round welding on the upper part where each side of the exhaust has a funnel shape.
https://rennlist.com/forums/parts-ma...an-1050-a.html
I hear a slight tone change with 0 performance changes when I installed mine. I don't even think it is 3dB louder than stock.
For the 987.2 and 981, I would recommend headers (catless or 200 cell) if you're looking for performance and increased volume. The exhaust only changes the tone.
12-09-2019, 01:42 AM
#19
I hear a slight tone change with 0 performance changes when I installed mine. I don't even think it is 3dB louder than stock.
For the 987.2 and 981, I would recommend headers (catless or 200 cell) if you're looking for performance and increased volume. The exhaust only changes the tone.
For the 987.2 and 981, I would recommend headers (catless or 200 cell) if you're looking for performance and increased volume. The exhaust only changes the tone.
12-12-2019, 11:03 AM
#20
12-13-2019, 09:46 PM
#21
Three Wheelin'
I drive a 987.2 S and am interested in similar PSE-mod for the native mufflers.
Particularly as secondhand, full systems, are as low as \5000 in Japan (USD50 or similar).
I had assumed the mod, based on PSE layout too, simply removed the segment of the main flow elbow as shown in many photographs.
The housing then to be cut, and re-welded accordingly to allow access.
Thanks!
12-17-2019, 12:39 PM
#22
I have the Carnewal modification on my '14 981 CS. When it arrived, I inspected the mufflers and they had not been cut open. The exhaust pipe leading into the mufflers had been cut off and rewelded back in place. I used a borescope to see what had been done internally. They apparently reached into the muffler and cut a round hole in the internal pipe, allowing louder sound similar to PSE. There is also a welded on support to help stabilize the inleading pipe.
The following users liked this post:
Liongolfer (12-18-2019)
12-18-2019, 10:42 AM
#23
I have the Carnewal modification on my '14 981 CS. When it arrived, I inspected the mufflers and they had not been cut open. The exhaust pipe leading into the mufflers had been cut off and rewelded back in place. I used a borescope to see what had been done internally. They apparently reached into the muffler and cut a round hole in the internal pipe, allowing louder sound similar to PSE. There is also a welded on support to help stabilize the inleading pipe.
Thanks man!
12-18-2019, 10:44 AM
#24
12-19-2019, 10:22 AM
#25
981 GT Muffler Mod $500
K' the deed is done!
We now have a fourth shop that can do this mod. Located in Southern California.
Brett is the Manager of the shop and the man I worked with directly on getting the job done.
Dropped the car off at 0800 in the morning and then went to work. Got the call it was finished at ~1pm (n' my car was one of many in line.. they had plenty of work going on).
They did the complete mod and installed the new Fabspeed X-pipe tip..
The word from Brett was "it definitely woke up the exhaust.. was now significantly louder and has burbles and pops on decel".
So before hand, I presented all of the known information collected in this thread to Brett.
I created a doc that outlined the two known methods..complete with pictures and then left the rest up to him.
I literally told him "you're the expert with the experience and the skills, you decide how best to do the job".
In our discussion (without any prompting from me), he basically repeated the known challenges we've talked about here and on the other forum..
Mostly the matter of properly re-sealing the muffler case with good welds on fairly thin stainless steal and creating a tight/solid seal.
He was eyeballing the baffle area deeper inside the muffler and was curious to know if there was any fiberglass packing etc.. what is the infrastructure the pipe projects into (exactly).
He also indicated that on many occasions they had done a similar mod to various BMW's.. so this was really not that much of an "unknown" to him and the shop.
In the end, he chose to crack the top of the muffler case and cut the elbow out like in the DIY picture. Only he cut out a smaller/more precise square section of the case.
Also said he re-enforced the weld around the inlet pipe from the inside.. Then sealed up the small square cut out section.
I crawled around under the car for a bit with a mirror and flashlights but couldn't get a glimpse of the cuts.. I'll keep checking.
But I'm also glad I can't tell.. looking at it from underneath it looks stock/OEM.
I asked.. but unfortunately he didn't take any pics.. perhaps there's a bit of a Muffler Shop Wall of Silence or something we're dealing with.. maybe they don't want to poke the Porsche Corp. bear. I dunno.
That's the only thing I was disappointed about.
The results (so far) are awesome! When Brett said "it definitely woke up the exhaust" he wasn't freakin' kidding.
It is significantly louder, but not too crazy loud. The tone is a bit deeper and definitely more pronounced and defined/refined.
Once the car is warmed up, at idle it sounds real nice.. pleasant even. Push the pedal a little bit and it starts to come alive. Push hard and she roars.
No drone so far, but haven't driven the highway yet in 5th and 6th gear.
The FabSpeed tips look awesome and I can already tell she's breathing a lot better. Very glad to have this mod done.
Over the holiday break next week I'll get some vids and sound recordings with decimeter SPL data.
$500 gents.. If you're in the SoCal area, call Brett and get it done, you won't regret it.
We now have a fourth shop that can do this mod. Located in Southern California.
Brett is the Manager of the shop and the man I worked with directly on getting the job done.
Dropped the car off at 0800 in the morning and then went to work. Got the call it was finished at ~1pm (n' my car was one of many in line.. they had plenty of work going on).
They did the complete mod and installed the new Fabspeed X-pipe tip..
The word from Brett was "it definitely woke up the exhaust.. was now significantly louder and has burbles and pops on decel".
So before hand, I presented all of the known information collected in this thread to Brett.
I created a doc that outlined the two known methods..complete with pictures and then left the rest up to him.
I literally told him "you're the expert with the experience and the skills, you decide how best to do the job".
In our discussion (without any prompting from me), he basically repeated the known challenges we've talked about here and on the other forum..
Mostly the matter of properly re-sealing the muffler case with good welds on fairly thin stainless steal and creating a tight/solid seal.
He was eyeballing the baffle area deeper inside the muffler and was curious to know if there was any fiberglass packing etc.. what is the infrastructure the pipe projects into (exactly).
He also indicated that on many occasions they had done a similar mod to various BMW's.. so this was really not that much of an "unknown" to him and the shop.
In the end, he chose to crack the top of the muffler case and cut the elbow out like in the DIY picture. Only he cut out a smaller/more precise square section of the case.
Also said he re-enforced the weld around the inlet pipe from the inside.. Then sealed up the small square cut out section.
I crawled around under the car for a bit with a mirror and flashlights but couldn't get a glimpse of the cuts.. I'll keep checking.
But I'm also glad I can't tell.. looking at it from underneath it looks stock/OEM.
I asked.. but unfortunately he didn't take any pics.. perhaps there's a bit of a Muffler Shop Wall of Silence or something we're dealing with.. maybe they don't want to poke the Porsche Corp. bear. I dunno.
That's the only thing I was disappointed about.
The results (so far) are awesome!
When Brett said "it definitely woke up the exhaust" he wasn't freakin' kidding.It is significantly louder, but not too crazy loud. The tone is a bit deeper and definitely more pronounced and defined/refined.
Once the car is warmed up, at idle it sounds real nice.. pleasant even. Push the pedal a little bit and it starts to come alive. Push hard and she roars.
No drone so far, but haven't driven the highway yet in 5th and 6th gear.
The FabSpeed tips look awesome and I can already tell she's breathing a lot better. Very glad to have this mod done.
Over the holiday break next week I'll get some vids and sound recordings with decimeter SPL data.
$500 gents.. If you're in the SoCal area, call Brett and get it done, you won't regret it.
12-20-2019, 10:22 AM
#26
No drone so far, but haven't driven the highway yet in 5th and 6th gear.
The FabSpeed tips look awesome and I can already tell she's breathing a lot better. Very glad to have this mod done.
$500 gents.. If you're in the SoCal area, call Brett and get it done, you won't regret it.
The FabSpeed tips look awesome and I can already tell she's breathing a lot better. Very glad to have this mod done.
$500 gents.. If you're in the SoCal area, call Brett and get it done, you won't regret it.
All the exhaust sounds are very much aft of the sitting position, so the mod has maintained the original muffler sound design.
Very interesting notes coming from this exhaust when shifting up and down..
Cold start in the morning is great. A great low end growl to start the day.
On down shift and rev match, the decel burble is really cool. Not very loud but definitely there.
Stabbing the throttle on upshift causes a quick barking sound at first, then its just the deep growl up to about 4K rpm, after 4K rpm it turns into a glorious howl.
Standard drive mode now sounds like Sport Mode.
Sport Mode is now the next level up.. maybe closer to Sport Plus. I don't have Sport Plus, so just guessing but its definitely more open and louder.
Right now I have the impression its settling into this new exhaust arrangement. The exhaust flow has definitely changed.
At idle, the engine has even less shimmy and vibration. Seems a smidgen more stable than before.
I'm definitely not hearing any more exhaust pulse collisions out the tip. The Fabspeed tip is doing a great job. That OEM T-Tip sooo suuuucckkks.
Gas mileage seemed to have taken a small hit at first (or I'm now pushing on the pedal more just to hear the new sounds), but I think the ECU is learning and adjusting to the affects on the MAS.
By the time I pulled into the driveway last night, the gas mileage appeared to be rising again.
No CELs or dash-lights either. A very good thing!
12-20-2019, 11:18 AM
#27
OK, NO DRONE on the highway in higher gears.
All the exhaust sounds are very much aft of the sitting position, so the mod has maintained the original muffler sound design.
Very interesting notes coming from this exhaust when shifting up and down..
Cold start in the morning is great. A great low end growl to start the day.
On down shift and rev match, the decel burble is really cool. Not very loud but definitely there.
Stabbing the throttle on upshift causes a quick barking sound at first, then its just the deep growl up to about 4K rpm, after 4K rpm it turns into a glorious howl.
Standard drive mode now sounds like Sport Mode.
Sport Mode is now the next level up.. maybe closer to Sport Plus. I don't have Sport Plus, so just guessing but its definitely more open and louder.
Right now I have the impression its settling into this new exhaust arrangement. The exhaust flow has definitely changed.
At idle, the engine has even less shimmy and vibration. Seems a smidgen more stable than before.
I'm definitely not hearing any more exhaust pulse collisions out the tip. The Fabspeed tip is doing a great job. That OEM T-Tip sooo suuuucckkks.
Gas mileage seemed to have taken a small hit at first (or I'm now pushing on the pedal more just to hear the new sounds), but I think the ECU is learning and adjusting to the affects on the MAS.
By the time I pulled into the driveway last night, the gas mileage appeared to be rising again.
No CELs or dash-lights either. A very good thing!
All the exhaust sounds are very much aft of the sitting position, so the mod has maintained the original muffler sound design.
Very interesting notes coming from this exhaust when shifting up and down..
Cold start in the morning is great. A great low end growl to start the day.
On down shift and rev match, the decel burble is really cool. Not very loud but definitely there.
Stabbing the throttle on upshift causes a quick barking sound at first, then its just the deep growl up to about 4K rpm, after 4K rpm it turns into a glorious howl.
Standard drive mode now sounds like Sport Mode.
Sport Mode is now the next level up.. maybe closer to Sport Plus. I don't have Sport Plus, so just guessing but its definitely more open and louder.
Right now I have the impression its settling into this new exhaust arrangement. The exhaust flow has definitely changed.
At idle, the engine has even less shimmy and vibration. Seems a smidgen more stable than before.
I'm definitely not hearing any more exhaust pulse collisions out the tip. The Fabspeed tip is doing a great job. That OEM T-Tip sooo suuuucckkks.
Gas mileage seemed to have taken a small hit at first (or I'm now pushing on the pedal more just to hear the new sounds), but I think the ECU is learning and adjusting to the affects on the MAS.
By the time I pulled into the driveway last night, the gas mileage appeared to be rising again.
No CELs or dash-lights either. A very good thing!
Great outcome and thanks for the update. Power wise, any low end loss and slight increase at the high end?
12-21-2019, 12:30 PM
#28
I don't perceive ANY low end loss whatsoever.. but I always drive in manual mode for direct access to all those sweet revs.
After she's warmed up, by default I'm driving between 3K-5K RPM.
If anything, she's a little more responsive and acceleration is a little smoother/stronger.
The grin on my face has become a little bigger and more permanent.
Videos and recordings next.
12-22-2019, 12:00 AM
#29
I've done 2 of these hacks on the 981; I'm the one who posted the video of the blue (modded) and gray (stock) exhaust comparison on youtube. I just want to clear up 2 things:
1. This is NOT the same as the Carnewal mod for the 981. As far as most of us (who've done the hack) can tell, this mod is more aggressive than Carnewal. Also, my friend's 981S which has Carnewal is clearly less aggressive than my current 981S.
2. The 987.2 exhaust is very different than the 981, and the mod you would do on that gen car would be identical to the Carnewal mod. The mod would also be easier, so far as I can tell, simply because fitup could be tight (fitup after cutting the hole sucks for the 981 mod, which makes the TIG part really hard). For the 987.2, I recommend 2 mods: remove the 2nd cat (which is inside the header, located behind the O2 port, but upstream of the outlet flange) and also mod the exhaust. On a 987.2 I had, I just removed the 2nd cat, and it wasn't enough of a difference... I'd recommend a bit more.
1. This is NOT the same as the Carnewal mod for the 981. As far as most of us (who've done the hack) can tell, this mod is more aggressive than Carnewal. Also, my friend's 981S which has Carnewal is clearly less aggressive than my current 981S.
2. The 987.2 exhaust is very different than the 981, and the mod you would do on that gen car would be identical to the Carnewal mod. The mod would also be easier, so far as I can tell, simply because fitup could be tight (fitup after cutting the hole sucks for the 981 mod, which makes the TIG part really hard). For the 987.2, I recommend 2 mods: remove the 2nd cat (which is inside the header, located behind the O2 port, but upstream of the outlet flange) and also mod the exhaust. On a 987.2 I had, I just removed the 2nd cat, and it wasn't enough of a difference... I'd recommend a bit more.
12-22-2019, 08:56 AM
#30
Because of your vid and my lack of available time, I did not make any "before/stock" recordings. I thought you covered it pretty well and it sounded exactly like my car (stock).
So thanks!
I just want to clear up 2 things:
1. This is NOT the same as the Carnewal mod for the 981. As far as most of us (who've done the hack) can tell, this mod is more aggressive than Carnewal. Also, my friend's 981S which has Carnewal is clearly less aggressive than my current 981S.
1. This is NOT the same as the Carnewal mod for the 981. As far as most of us (who've done the hack) can tell, this mod is more aggressive than Carnewal. Also, my friend's 981S which has Carnewal is clearly less aggressive than my current 981S.
Yesterday, I captured a "Cold Start" recording (w/ video and separate stereo audio recorder) complete with readings from a Sound Pressure Level Meter (SPL) and it is definitely a bit louder than I had anticipated.
IMHO, still not crazy loud and doesn't seem to pack as much sustained punch as other aftermarket exhaust systems.
Gonna try and get more recordings today, then will do a little editing and post work before publishing.
Loving this mod!