Aftermarket exhaust questions and comparisons
10-22-2014, 05:22 PM
#16
Rennlist Member
Dan,
Can you pls tell me what the db sound/loud reading is btw stock and your bypass at idle?
I'm mostly interested in the under 4000 rpm sound, before the GT3 electros open up the exhaust.
I think the stock sound below 4000 rpms sounds like most DFI engines. It basically sucks. The sound is suppressed...
Cheers & TIA,
BB
Can you pls tell me what the db sound/loud reading is btw stock and your bypass at idle?
I'm mostly interested in the under 4000 rpm sound, before the GT3 electros open up the exhaust.
I think the stock sound below 4000 rpms sounds like most DFI engines. It basically sucks. The sound is suppressed...
Cheers & TIA,
BB
10-22-2014, 05:47 PM
#17
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Thanks guys - actually I just found those images on a Google search and judging from the file name they're from Europipe! (www.europipe.be)
Hi Ben - For that you might want to use a remote or force the valves open (cap the vac lines). I don't have any meaningful #s unfortunately, we have tried taking measurements but the numbers end up all over the chart, but next time we have a 991 GT3 in I'll try a before and after below 4000 RPMs and idle.
Hi Ben - For that you might want to use a remote or force the valves open (cap the vac lines). I don't have any meaningful #s unfortunately, we have tried taking measurements but the numbers end up all over the chart, but next time we have a 991 GT3 in I'll try a before and after below 4000 RPMs and idle.
__________________
Dan Kennedy
SharkWerks: www.sharkwerks.com
Northern California's Porsche Performance, & authorized Evolution Motorsports, TechArt, HRE and Tubi, Cargraphic dealer and installation center
Phone: 510-651-0300
Email: dan@sharkwerks.com
SharkWerks' Latest Updates on Twitter
Dan Kennedy
SharkWerks: www.sharkwerks.com
Northern California's Porsche Performance, & authorized Evolution Motorsports, TechArt, HRE and Tubi, Cargraphic dealer and installation center
Phone: 510-651-0300
Email: dan@sharkwerks.com
SharkWerks' Latest Updates on Twitter
10-22-2014, 07:22 PM
#18
The day after I picked my GT3 I went to the drag strip just to see what it will do.
I ran consistent low 125mph passes.
3 days later installed a center muffler replacement (doesn't matter what brand).
I noticed straight away the car had lost some "zing".
When back to the strip and I was right...ran consistent high 122mph passes.
A few days ago I re-installed the factory center muffler...the "zing" is back
I haven't been back to the strip but it definitely faster now…
What may have happened??....scavenging effect reduced by removal of the center muffler??
I ran consistent low 125mph passes.
3 days later installed a center muffler replacement (doesn't matter what brand).
I noticed straight away the car had lost some "zing".
When back to the strip and I was right...ran consistent high 122mph passes.
A few days ago I re-installed the factory center muffler...the "zing" is back
I haven't been back to the strip but it definitely faster now…
What may have happened??....scavenging effect reduced by removal of the center muffler??
10-22-2014, 07:24 PM
#19
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We've dynoed our exhaust systems plenty of times and never seen a power loss from the bypass. Considering the back pressure the car has I would be surprised if removing the center muffler caused any power loss. But this is interesting and I'd like to see your time slips and hear more.
10-22-2014, 08:34 PM
#20
Dan,
Do you expect a loss in power/torque by forcing the valves open after disconnecting the vacuum lines? I think you've sold me on the SW bypass.
Do you expect a loss in power/torque by forcing the valves open after disconnecting the vacuum lines? I think you've sold me on the SW bypass.
10-22-2014, 08:36 PM
#21
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I think that's more likely, especially for a little of the torque < 4000 RPMs. But I'd want to see a dyno to confirm that. Also these cars pretty much spend their entire lives over 4000 RPMs when they aren't in traffic so I wouldn't be too concerned 
The remote's a nice alternative so you can switch it open or closed when needed.
The remote's a nice alternative so you can switch it open or closed when needed.
10-22-2014, 08:42 PM
#22
Three Wheelin'
Hey Dan,
I have a SW bypass for my upcoming GT3.
I asked dealership to install it after it arrives in January.
I had Alex send me the install instructions before the part came to give to my dealer, they told me it was a 5 hour install.
Does this sound right??
I have a SW bypass for my upcoming GT3.
I asked dealership to install it after it arrives in January.
I had Alex send me the install instructions before the part came to give to my dealer, they told me it was a 5 hour install.
Does this sound right??
10-22-2014, 08:48 PM
#23
Burning Brakes
No! Absolutely not. Its an hour. This is confirmed by Alex and by two different dealers (Hennessy and Porsche of Chattanooga). There is no bumper removal.
10-22-2014, 08:49 PM
#24
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No, it's very easy. We usually take about 1 hour, maybe 1:30 including cooling down, putting it on the lift etc. They may have been thinking that the rear bumper and/or side mufflers had to be removed, which is a lot more work.
On the 991 GT3 (unlike the 997 GT3, which is about a 2 hour installation) you can leave the bumper cover installed. You just need to loosen a handful of bolts and nuts, lift one muffler out, and slide the SW exhaust on and re-tighten everything. 5 hours is very excessive - they may have just not wanted to do it (and I can understand that), but if they have installed one before they would know that it's really easy. I might suggest another dealer..
On the 991 GT3 (unlike the 997 GT3, which is about a 2 hour installation) you can leave the bumper cover installed. You just need to loosen a handful of bolts and nuts, lift one muffler out, and slide the SW exhaust on and re-tighten everything. 5 hours is very excessive - they may have just not wanted to do it (and I can understand that), but if they have installed one before they would know that it's really easy. I might suggest another dealer..
10-22-2014, 08:49 PM
#25
Nordschleife Master
Hi Ken - I can't speak on behalf of the other manufacturers but I'll try to help with these.
I've heard a lot and to be honest they all sound pretty good I think ours sounds best but of course I'm a bit biased! We make ours in California using American stainless steel. I'm sure any of these have good build quality. Akrapovic is made of titanium which is a bit lighter, but I believe more susceptible to cracks and failures. Any that replace the side mufflers will be harder to install and remove. Our center system installs in about an hour on a 991 GT3. No bumper or wheel removal is required. Aesthetics depends on your wants but our system looks like OEM from the outside, you can re-use the stock tips or use ours if you prefer. Not sure on dB measurements vs the others.
Not sure on the others but yes the center exhaust will let you use the Sport button. I'm guessing the others do too.
We charge $1500 for the exhaust and $150 for the install here of our system.
Again I'm a bit biased here but I've driven a 1500 mile drive in the GT3RS with our exhaust installed. With the sport button off it's about the same comfort level and cruising volume of stock.
Correct we use the stock tailpipe flange so you can re-use the stock tips or install our aftermarket tips:
Any of these systems can be removed within a few hours so I wouldn't worry about resale value. You can just remove them when you're done and sell the car as stock instead (or at least give the buyer the option). No matter which exhaust you install I'd recommend keeping the stock parts.
Our bypass does make it louder at low RPMs as well. It's bypassing the center muffler so it never mutes it as it originally intended, even at lower RPMs. The other option is to force the values open on the side muffler at low RPMs, which I recommend this device for:
http://www.carnewal.com/products/P97...Manual-Control
Not sure if this works on the 991 GT3 yet^^
I've heard a lot and to be honest they all sound pretty good
I think ours sounds best but of course I'm a bit biased! We make ours in California using American stainless steel. I'm sure any of these have good build quality. Akrapovic is made of titanium which is a bit lighter, but I believe more susceptible to cracks and failures. Any that replace the side mufflers will be harder to install and remove. Our center system installs in about an hour on a 991 GT3. No bumper or wheel removal is required. Aesthetics depends on your wants but our system looks like OEM from the outside, you can re-use the stock tips or use ours if you prefer. Not sure on dB measurements vs the others.Not sure on the others but yes the center exhaust will let you use the Sport button. I'm guessing the others do too.
We charge $1500 for the exhaust and $150 for the install here of our system.
Again I'm a bit biased here but I've driven a 1500 mile drive in the GT3RS with our exhaust installed. With the sport button off it's about the same comfort level and cruising volume of stock.
Correct we use the stock tailpipe flange so you can re-use the stock tips or install our aftermarket tips:
Any of these systems can be removed within a few hours so I wouldn't worry about resale value. You can just remove them when you're done and sell the car as stock instead (or at least give the buyer the option). No matter which exhaust you install I'd recommend keeping the stock parts.
Our bypass does make it louder at low RPMs as well. It's bypassing the center muffler so it never mutes it as it originally intended, even at lower RPMs. The other option is to force the values open on the side muffler at low RPMs, which I recommend this device for:
http://www.carnewal.com/products/P97...Manual-Control
Not sure if this works on the 991 GT3 yet^^
10-22-2014, 08:50 PM
#26
I think that's more likely, especially for a little of the torque < 4000 RPMs. But I'd want to see a dyno to confirm that. Also these cars pretty much spend their entire lives over 4000 RPMs when they aren't in traffic so I wouldn't be too concerned The remote's a nice alternative so you can switch it open or closed when needed.
The remote's a nice alternative so you can switch it open or closed when needed.
10-22-2014, 08:55 PM
#27
Burning Brakes
Ken, now we just need to talk Sean and Mayur into SWs. Then we can all hit tunnel on 400 and upshift at 9K in unison! Can you imagine what that will sound like? Several GoPros will be required!
10-22-2014, 09:50 PM
#28
Three Wheelin'
No, it's very easy. We usually take about 1 hour, maybe 1:30 including cooling down, putting it on the lift etc. They may have been thinking that the rear bumper and/or side mufflers had to be removed, which is a lot more work.
On the 991 GT3 (unlike the 997 GT3, which is about a 2 hour installation) you can leave the bumper cover installed. You just need to loosen a handful of bolts and nuts, lift one muffler out, and slide the SW exhaust on and re-tighten everything. 5 hours is very excessive - they may have just not wanted to do it (and I can understand that), but if they have installed one before they would know that it's really easy. I might suggest another dealer..
On the 991 GT3 (unlike the 997 GT3, which is about a 2 hour installation) you can leave the bumper cover installed. You just need to loosen a handful of bolts and nuts, lift one muffler out, and slide the SW exhaust on and re-tighten everything. 5 hours is very excessive - they may have just not wanted to do it (and I can understand that), but if they have installed one before they would know that it's really easy. I might suggest another dealer..
If you have another one near me, I'd welcome your suggestions.
10-22-2014, 10:19 PM
#29
I see the rear muffler has a crossover pipe, but the sharkwerks doesn't. What are the advantages/disadvantages of the crossover pipe and why wasn't one incorporated into the SW design?
10-22-2014, 11:28 PM
#30
