Consensus on stock exhaust and, who is considering getting an AM system?
07-10-2014, 09:20 PM
#151
I think what speed21 is referring to is a gear wrench. 
Let's face it : I haven't worked on a 991TT,but knowing Porsche,I am pretty sure they haven't changed the design so drastically that it's something we've never seen from previous Turbo generations. Yes,the intercooler is in the way so you can't really come with a power tool and extension/socket set up from the front but a gear wrench will do that job instead. Either way removing the intercoolers is a breeze if you had to,not to mention you're dealing with brand new fasteners without any rust. I'd say for someone that's done it before,it shouldn't take more than 2-3 hours.
P.S. Here's an illustration from the 996TT. 4 studs secure the cat to the turbocharger with 4 nuts and washers : No 7 and No 8 in the picture.
Let's face it : I haven't worked on a 991TT,but knowing Porsche,I am pretty sure they haven't changed the design so drastically that it's something we've never seen from previous Turbo generations. Yes,the intercooler is in the way so you can't really come with a power tool and extension/socket set up from the front but a gear wrench will do that job instead. Either way removing the intercoolers is a breeze if you had to,not to mention you're dealing with brand new fasteners without any rust. I'd say for someone that's done it before,it shouldn't take more than 2-3 hours. P.S. Here's an illustration from the 996TT. 4 studs secure the cat to the turbocharger with 4 nuts and washers : No 7 and No 8 in the picture.
I can understand in a wham bamm thank you mam type of job short cut$ can and are taken, and things aren't cleaned down and put back like new by the fitter, 02 wires can be knotted and twisted up ( I mean if the owner can't see it, it won't hurt and if they fail later then se la vie...**** happens). Well, me personally, on a car of this value I'd prefer the extra time spent on getting everything perfect and pay for that willingly, but that is just me and may not necessarily apply to everyone and every job.
Here is a shot of the tools supplied by EP for the job. Note the ratchet type wrench and fixed wrench with bend. These really do the job! The other tools are for the Torx screws in the wheel arches etc...to remove splash guards etc. Also supplied are 2 new flange gaskets and all new nuts etc....so it represents a nice package for the installer to speed up the job!
Last edited by speed21; 07-10-2014 at 10:03 PM. Reason: add photo
07-10-2014, 11:32 PM
#152
Thanks neanicu for the diagram and so on. The gear wrench you speak of is also referred to as a craftsman's wrench, and many toolboxes unfortunately don't have one, even at certain official dealerships. Having the right tools is great for jobs like these where the usual ringy, open ender or socket can't achieve access or motion on the nut.. Agree removing the IC's is no big deal so long as you are mindful of the retainer clips when reattaching the pressure lines as I have frequently heard and read of cases where they have later blown out under pressure due to a lack of attention upon re installation... to make sure the snap locks are properly locked iykwim. That one really needs to be closely watched for. That said if you can avoid removing the IC's it is better in the sense everything remains undisturbed from factory plus time is certainly saved. Time is $ as you know....unless you are doing it yourself. I think 2 to 3 hours is possibly achievable for the well rehearsed but most would find this job takes longer on the basis of ensuring everything is spot on and not just thrown together in a race over time. The sensors are time consuming to get everything perfect and you want that on a car like this. The EP cats, and most AM cats also don't share the same sensor locations in the actual cat and that can mean a bit of fiddling in getting the wires positioned evenly upon re installation so there is no stress on any of them when everything goes back into place. Seeing how the job is done I can fully understand the need for care in that area. To gain good access it is also better to lower the rear of the engine by releasing the rear mounts so it drops by an inch or so, which can also help in accessing the wires between the engine and body. I can understand in a wham bamm thank you mam type of job short cut$ can and are taken, and things aren't cleaned down and put back like new by the fitter, 02 wires can be knotted and twisted up ( I mean if the owner can't see it, it won't hurt and if they fail later then se la vie...**** happens). Well, me personally, on a car of this value I'd prefer the extra time spent on getting everything perfect and pay for that willingly, but that is just me and may not necessarily apply to everyone and every job. Here is a shot of the tools supplied by EP for the job. Note the ratchet type wrench and fixed wrench with bend. These really do the job! The other tools are for the Torx screws in the wheel arches etc...to remove splash guards etc. Also supplied are 2 new flange gaskets and all new nuts etc....so it represents a nice package for the installer to speed up the job!
07-11-2014, 12:26 AM
#153
Nordschleife Master
Yes. This is what I'm referring to as a gear wrench. It has a ratcheting mechanism inside so you don't have to remove it each time you're turning the nut. Flip it over and it goes the other direction. I particularly love mine because it bends to a desired angle. I believe the size nuts are 13mm. Might be different on the 991TT.
Also,there shouldn't be any reason to lower the engine. There's enough room to fish the wiring in between the chassis. It is held in by metal clamps so you need to slide it off those. Be careful disconnecting the O2 connectors,especially on the upstream sensor. They twist right out of the cats if you have a proper O2 sensor tool. It is the same process fitting them into the new cat,just make sure-very important- that you are putting the O2s exactly where they came out since the upstream is different than the downstream.
Also,there shouldn't be any reason to lower the engine. There's enough room to fish the wiring in between the chassis. It is held in by metal clamps so you need to slide it off those. Be careful disconnecting the O2 connectors,especially on the upstream sensor. They twist right out of the cats if you have a proper O2 sensor tool. It is the same process fitting them into the new cat,just make sure-very important- that you are putting the O2s exactly where they came out since the upstream is different than the downstream.
Last edited by neanicu; 08-31-2016 at 09:00 AM.
07-11-2014, 03:49 PM
#155
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I have to say the stock system really does sound good vs the previous 997.2tt and 997.1tt. It's clear that they made an effort or at least a lot more than the last go around. A few of our local California based sharks still wanted more sound- at least on the outside and with the windows down. The dealers here and emissions are strict so changing cats is a no no for street cars... So we sort of did something similar to the 997.2 set up we had. That one is louder outside but still doesn't drone inside. If we were to do something like that on the gen1 TT however it _would_. The dfi engine, cats etc... on the later cars do allow one to get a good bit more open that's for sure.
I've got a blown ear drum from surfing a couple of years ago so I'm a lot more of a wuss than I used to be and sensitive to drone. This time around was certainly more complex with more tubing, bends, welds etc... And like speed21 says the stock one kind of / sort of has some to it. I didn't want to add anymore that's for sure. So in the end we didn't induce more drone. It does burble a lot more (some might like and some may not), hiss with turbo spool etc... but since we're still retaining the stock cats we're compliant here for warranty/emissions purposes. If I were going for power etc... I'd use higher-flow cats but I don't think I would do so in combination with ours as it would get too loud (at least for me). For now we'll be offering it locally and to folks that had our 997.2TT set up...
Porsche 991 Turbo S SharkWerks Exhaust - YouTube
I've got a blown ear drum from surfing a couple of years ago so I'm a lot more of a wuss than I used to be and sensitive to drone. This time around was certainly more complex with more tubing, bends, welds etc... And like speed21 says the stock one kind of / sort of has some to it. I didn't want to add anymore that's for sure. So in the end we didn't induce more drone. It does burble a lot more (some might like and some may not), hiss with turbo spool etc... but since we're still retaining the stock cats we're compliant here for warranty/emissions purposes. If I were going for power etc... I'd use higher-flow cats but I don't think I would do so in combination with ours as it would get too loud (at least for me). For now we'll be offering it locally and to folks that had our 997.2TT set up...
Porsche 991 Turbo S SharkWerks Exhaust - YouTube
07-16-2014, 08:22 AM
#157
600. EP is 100 and most other 200. OEM cats are the same as the 997tt...both 600.
Congrats. Let us know your thoughts once you have it on. Mine gets better by the day.
07-16-2014, 09:21 AM
#158
Thanks. I suspect the way my car is being held at the port that the exhaust may get to the dealer before my car does. I will have them put it on before delivery. I will never know what the stock exhaust sounds like.
07-24-2014, 04:10 PM
#159
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07-28-2014, 07:56 PM
#162
Hey Alex I note your SharkWerks cross pipe thankfully does not make any of that ridiculous gunshot like Fabspeed catless and the Cargraphic Y pipe, both which appear to use that same design Y collector. I assume they are both sourcing it from Jim's Taiwan? It sure does looks the same y collector anyway..
Please quote me if I am wrong, but it appears this restrictive looking Y collector box is behind the shotgun problem or has something to do with it? It appears to have been made as a component so to accommodate a large range of vehicle set ups....i.e a one size fits all. A bit like the imported mufflers I suspect. All that is required from there on is basically a few mandrel bent pipes welded to these two components in a jig and voila they can basically produce an AM system for virtually any car or model..... to max out profit margins. Not a bad business model if I must say. Just price up the system depending on the car it is going on to....
Please quote me if I am wrong, but it appears this restrictive looking Y collector box is behind the shotgun problem or has something to do with it? It appears to have been made as a component so to accommodate a large range of vehicle set ups....i.e a one size fits all. A bit like the imported mufflers I suspect. All that is required from there on is basically a few mandrel bent pipes welded to these two components in a jig and voila they can basically produce an AM system for virtually any car or model..... to max out profit margins. Not a bad business model if I must say. Just price up the system depending on the car it is going on to....
07-28-2014, 08:33 PM
#163
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Hey Alex I note your SharkWerks cross pipe thankfully does not make any of that ridiculous gunshot like Fabspeed catless and the Cargraphic Y pipe, both which appear to use that same design Y collector. I assume they are both sourcing it from Jim's Taiwan? It sure does looks the same y collector anyway..
Please quote me if I am wrong, but it appears this restrictive looking Y collector box is behind the shotgun problem or has something to do with it? It appears to have been made as a component so to accommodate a large range of vehicle set ups....i.e a one size fits all. A bit like the imported mufflers I suspect. All that is required from there on is basically a few mandrel bent pipes welded to these two components in a jig and voila they can basically produce an AM system for virtually any car or model..... to max out profit margins. Not a bad business model if I must say. Just price up the system depending on the car it is going on to....
Please quote me if I am wrong, but it appears this restrictive looking Y collector box is behind the shotgun problem or has something to do with it? It appears to have been made as a component so to accommodate a large range of vehicle set ups....i.e a one size fits all. A bit like the imported mufflers I suspect. All that is required from there on is basically a few mandrel bent pipes welded to these two components in a jig and voila they can basically produce an AM system for virtually any car or model..... to max out profit margins. Not a bad business model if I must say. Just price up the system depending on the car it is going on to....
07-28-2014, 11:20 PM
#164
I guess fluid dynamics and obvious path of least resistance and reduced back pressure wasn't taught in some schools. Not sure what the obsession is with this X on a turbo car is (I guess it's a cheap piece to make and buy from there even if one is exploiting a bunch of underage workers) I can't say it sounds as good as an EP (they always have a unique sound and I haven't yet heard one) but with stock cats there's no drone/resonance and it's got a bit of oomph to it! With the DFI engine I liked our 997.2 set up and this is close that if you will.
LOL. BS really does baffle brains.
Last edited by speed21; 07-29-2014 at 02:32 AM.
07-29-2014, 05:24 PM
#165
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Still curious to know what these nice toys sound like from where it matters most of the time..._inside_ the cabin...when compared to stock. I can imagine why it's hard (not really fair even) to assess these systems from exterior cameras with wind and other environmental noise (and to judge by most samples I've heard so far nothing more than on-camera mics which are...well, basic). From inside with a decent mic...at least for me a side-by-side of stock versus AM might be even more compelling.