turbolou

Since I have never experienced the perf. of my 08 997 turbo with a stock muffler & it has had a Fab-speed system on it ever since I have owned it. Can someone honestly tell me if there is a noticeable gain over a stock muffler. I should add that the tune is stock also & have no intention of tampering with it & voiding my warranty as the car seems fast enough already. I'm rather dubious of some of the claims for & against this question. I'm sure somewhere here it has been asked before but I cant find it. If there are any qualified Porsche technicians reading this I would like to hear your opinion. I just find it hard to believe the Porsche engineers would release an inferior exhaust system on a car of this caliber begin with.

jhbrennan

I think both AWE and Fab list before and after dyno results...believe what you want.

dianic

I believe so. I have recently upgraded my exhaust to a Europipe Stage 1, and the results I have are at the higher end of my expectations. Not only audibly (stock sounds is inadequate in my view, especially after a non turbo car with PSE) but also from a performance perspective. And it doesnt just boil down to hp gains. The car breaths easier, the turbos spool faster, and I can hear them too. Also, what has really been transformed is the tiptronic transmission. The better than stock breathing (and this is simply reduced backpressure) means that the tip noticeably more sensitive to my input on the gas pedal. It downshifts quicker, and is more responsive, even on high speeds on the highway, where it will drop to 4th even with a 10-15% pedal squeeze.

I would never go back to stock, there are too many advantages.

TT Gasman

It's not that the OEM exhaust us inferior, but it's crippled by restrictive cats. Turbo motors make more power with less backpressure and the turbos spool quicker. A decent exhaust should give an easy 20 hp on this motor, and 500 hp is plenty on the street.

jcnesq

No dyno or technical input, however, when I switched out of OEM to Milltek, I was sure seat-of-the-pants I could feel some extra HP and the car breathing better. And of course the cats are probably a big part of that.

avader906

OEM exhaust system design is a compomise between performance vs. emissions and noise regulations in different markets. On the 997tt the following components could be upgraded: manifold, cats, mufflers and piping. Least costly upgrade are mufflers and could in practice only yield weight reduction benefits (which are as important as horsepower). In terms of performance, eliminating and/or redesigning the flow of manifolds as well as less restrictive cats provide most of tunable gains. In my experience Porsche would not void warranty if there is no link between the fault(s) and after-market parts - in particular air filter/mufflers/cats. Again this is not a question of quality of Porsche design but simple consideration behind mass production of cars for markets with different emissions regulations (often taking the lowest common denominator approach). Porsche has a long motorsport history and often offers factory upgrades for track or performance oriented customers. Example: "Sport Exhaust" is an option available on many 997 models. Most of non factory after market parts are developed by private racing teams on the basis of their real racing experience and often with factory collaboration.

turbolou

I 'm standing over the stock exhaust system looking at it & debating if I should put it back on. The cats are not so restrictive & the mufflers way better quality than the aftermarket system currently on my car. the millions that went into the design & the brain trust behind it cannot be duplicated by some guy working out of his garage dreaming about getting rich & selling Chinese knock offs. Because something you can bolt on & make a little more noise doesn't convince me that its better . That is my point & need actual dyno tests & hard facts from a neutral Porsche expert that anyone's Else's system is actually better. I guess the only way I will be convinced is to swap it out & try it for myself.

jhbrennan

Did you go to the Fabspeed website and look at their dyno postings? Maybe not "neutral" but last time I looked they weren't in China either.

E55AMG

I remember talking with Mike Levitas, owner of TPC Racing. Mike knows his stuff, and is a 24hr. Daytona winner. I don't remember the specifics but he was telling me of a customer who brought in his car with some minor mods - intake and I think headers.

The customer had claimed this package should have given him 25HP or so. Mike dyno'd the car and said "not bad only 14HP". the customer was irate and said "only gained 14HP"? "No", Mike said - "only LOST 14HP" LOL

While TPC sells EP exhaust, Mike is a big fan of the stock exhaust - particularly the headers. I'm not technical enough to get into it but I know people immediately will claim how restrictive the stock Cats are (600 cell or something like that?). Don't recall the entire conversation but Mike had told me that there is more to it than just that, and the stock exhaust shouldn't be dismissed simply for that.

avader906

Not sure I understood your original question. GT2 RS comes with full titanium Akrapovic exhaust from the factory; to give you an example of after-market system adopted and used by Porsche in its product(s). The question one would ask is..... why doesn't 997tt have it or conversly why GT2 RS doesn't use 997tt oem system.

Otherwise you highlight 3 separate issues: the aftermarket system you have reservations against, real value of "tuning"/aftermarket parts, porsche branding vs. product development.

dianic

I, for one would be very interested to read your opinion if you were to swap back to stock...

sbkim

LOL - that is one funny story! Although I am not sure if that customer would agree...

I've always had aftermarket exhaust on my fun cars - abeit none were Porsches... but I've normally got them to enhance sound as opposed to power. However, I do distrinctly remember one time I added long tube headers and I lost tons of low end torque which I was NOT too happy with.

I know this sounds counter intuitive but I am actually thinking about keeping the stock system and running a tune to add more power. This way, I can save 2-3K towards the tune.

cparkin

I was there that day Chris, Europipe and Akrapovic are the best out there... hands down.

OmahaGT

Check out this system for sale:

https://rennlist.com/forums/997-turb...-for-sale.html

JB 911

I would be interested too to see if you bolt the stock back on how you'd like it.

I don"t have one yet a tt or any porsche (I'm planning on a tt)but I do have an engineering degree and with that I will say certainly without a doubt an aftermarket system could improve performance. But I equally agree with the person said some might actaully cost you performance. Theres a huge difference between muffler only and cat back. And taking any after markets data should be done with a grain of salt. I doubt one in a hundred actaully dyno their car before and after. Even with no gain, someone spends money, its louder, of course they are gonna say it drives better or they look like a foo-ool.

I don't want it to be loud for me the quieter the better so I'd probably stay stock. I thought you only needed noise for Camaros and stangs