centaur

Headers usually give a nice gain on most vehicles along with good sound characteristics. Catbacks can easily be 3 or 4 grand, terrible value for 10 HP if that which could be some dyno manipulation to show a desired result.

breny4104

Akropovic shows 10 HP/10LB-FT gain on their slip ons but they don't mention which trim (base or s). I couldn't feel seat of the pants increase in performance on my base, and mainly got them for the sound - and because they looked cool. The Akropovic are 20LBS lighter and there may be some marginal gain from the weight reduction.

centaur

Akropovic makes quality products. Their stuff always sounds great. Never hurts to loose 20 lbs either.

Tupper

Kindly do me a favor and point me to dyno proof somewhere that this is true. Specifically, that headers create greater gains than a catback exhaust.

Saying “It’s a well know fact in the industry” unfortunately doesn’t it cut it for me. Particularly when I’m considering paying thousands of dollars.

APEX GT3

BMW Video... I appreciate the intent to show how adding performance exhaust can help power #’s but that has nothing to do with a Porsche 911. The video is showing a BMW 3 series, that is not a sports car. Might as well show a Toyota Camry. If the video was for a M3CS with the OEM performance exhaust that was replaced by an aftermarket option then I’d maybe consider the point you are trying to make. No offense.
However, we are talking about a 992 Porsche 911 with a performance sport exhaust system (which is an EXPENSIVE option). The system has been optimized and designed by Porsche engineers. The restrictive part of the car is the cats, so grab Soul or Fabspeed. As for the Headers, I think SOUL has developed a pretty good design which should increase power and throttle response and a bit of sound.

I’m just not sold on removing the Porsche sport exhaust (PSE). I can understand if it was the regular stock exhaust - but it’s not.

APEX GT3

Funny you say that, SOUL makes one of the only larger diameter exhaust options so that would be the one to consider - after speaking directly to them, they told me to “just do the headers and sport cat for power if I had the PSE”. That being said, I’ve made up my mind to save the 4K. Better spent on a MEngineering tune IMO

VektorPerformance

The changes between the 991.2 and 992 engines are minimal. We do not make 992 products yet, but from our 991.2 testing, if you're below 500whp, the stock cat-back it's a bottleneck. Will it add some? Sure, but depending on trim and mods, you're going to be in the 5-10hp range. Well-designed headers and HF cats combined will add +25whp and nearly double that with an accompanying tune to bring back boost.

With headers and HF cats you'll notice a bump in power everywhere in the rev range, but you'll also notice a reduction in boost once the ECU relearns the VE changes. A custom tune can be used to bring boost levels back to where they were, and the timing can be a touch more aggressive due to the reduce post turbine backpressure.

centaur

Is there any reason why you cannot do your own research on the subject as it is abundantly clear that you are in need of a significant degree of enlightenment.
There are numerous posters here indicating to you that the restrictions on the exhaust side are reduced to the greatest degree with headers and "sport" type catalytics not cat backs.
Exhaust headers have been a corner stone of performance enhancement for over 70 years and that my dubious friend is a VERY well known fact whether you beleive so or not.
A few simple Google searches will yield more results attesting to this than one would ever care to read. No offense but you are in no position to question anyone who has had considerable experience with this stuff for decades. Do some home work.

centaur

dup

Tupper

The BMW M340i that was in the video is not “another 3 series”. Unlike the regular 3 series (an in-line 4 that makes 255 hp), it is an in-line 6 that makes 382 hp.

It is a turbocharged in-line 6 that makes 382 hp and has been clocked doing 0-60 by Car and Driver in 3.8 seconds stock. So it already is almost as fast in a straight line as a base Carrera and is down a bit in power compared to the S. I don’t think you can dismiss the video that I posted so easily.

Yes, every exhaust set up is different. But saying that “you might as well put a Toyota Camry on a dyno” is kind of ridiculous when you look at the numbers.

Tupper

I am doing research. But you have repeatedly, almost dismissively, kept hammering the point that an aftermarket exhaust makes zero power while headers make a much more substantial difference. Fine. Then back up what you say. Otherwise, you are just stating an opinion.

I am not saying that you are wrong. But how about backing it up?

I posted a video showing about a 12 hp gain just with a catback exhaust. I already concede that the power gains are pretty small (I never stated otherwise). I don’t see you posting anything here.

centaur

Your comments are absolutely spot on and obviously shared by the professionals you have spoken with. Unfortunately your efforts are falling on deaf ears as are mine.
The tune will yield a ton of power and should come first.

Tupper

My ears are wide open. And all you have is “I heard it from my elders”

Give me a break. Show up with data or stop wasting my time. No offense, but when it comes to my money I want results.

centaur

I am in no way obligated to educate you and have no intention of debating this subject.
Modifying performance vehicles is a great hoby that I have enjoyed for nearly 40 years and hope that you will find great satisfaction in this endeavor as I have.
Good luck with what ever you decide on. All the Best.

Tupper

Porsche PSE is very restrictive. When the valves are closed or mostly closed (vast majority of your driving), your exhaust is flowing through a 1.5 inch pipe into a perforated chamber where exhaust gases mingle together before exiting out another 1.5 inch pipe. This is to reduce sound and is also speculated to have something to do with emissions.

Here is an analysis of PSE by Fabspeed Motorsports. It’s the Turbo but I’m sure they are doing something very similar with the Carrera: