jnkirk1974

I'm really loving the sound of the PSE on the 991.2 GTS. Trying to decide which will give me more volume in the sound of the exhaust. Headers or cats?
Which is the best bang or the buck, if you could only choose one of them? Will there be a noticeable change with just cats?

medtech_expat

jnkirk1974

Thank you. That was my thought as well. I'm sure both work great together. However, I just assumed that cats had a bigger impact on the volume and headers had a bigger impact on performance. Obviously, cats also affect performance (and headers on sound).
Really, I'm just looking for more volume right now. Leaning towards cats for the time being.

vodkag

Cat, because that's is going to be you bottleneck down the exhaust line.

Say if you have a bigger header, you are still restricted by the volume of the cat

(obviously do both if you can LOL, but for us with the crazy CA emission restriction, i would not dare to touch the cat due to smog reasons)

Fabspeed Motorsport

Scott here from Fabspeed Motorsport, in my opinion, changing the Catalytic converters will give you the difference in sound that you are looking for. Your stock Cats have way more catalytic cells, less free flowing, and all around "slow down" the performance of your exhaust. We offer 200 Cell HJS high flow catalytic converters.


Take a listen to the sample with our Sport cats and carbon tips and let me know what you think!! Feel free to reach out to me regarding any questions, and Forum pricing!!


>>> <<<

LavaGTS

Bypass pipes without a doubt.

Headers will change the engine pulses which can change the exhaust note. Currently have fabspeed but want to switch to Kline or Vektor(they have proven nice gains).

Soul Performance

Sport Catalytic Converters are a prime choice to increase both turbo sound and engine sound while improving power slightly. HJS HD 200 cell catalysts prevent fumes and check engine lights.


Cat Bypass Pipes sound incredible if you want to go even further, but you'll need either O2 spacers or an ECU tune to prevent a check engine light


The headers will not offer as great of a difference in sound, but do pair well to increase power and sound if you are looking for both after that upgrade.

Happy to chat if you have more questions!

AutoQuest Motorsports

You are quite on point with this assumption. On PSE equipped cars such as yours, the cats have a much bigger effect on the sound as with valves open the muffler is a relatively straight through system. On Non-PSE cars a change in the muffler system makes a more notable improvement in exhaust note than a change in the cats. On both Non-PSE and PSE cars the headers make little difference in the sound as they are located before the turbos. Headers do compliment the performance of a cat change, but I wouldn't expect any notable improvement or change in sound by adding headers to a 991.2. Ditching the factory cats is definitely the way to go to meet your goals. If you'd like to chat a bit about the different versions on the market, as well as sport cat vs catless, tuning, CEL occurrences, etc, I'd be happy to spend some time with you to make an educated decision moving forward. My cell is 484 883 6197 and you can text/call me any time, it would be great to chat with you and hear about your experience with the car so far.

BulldogR6

+1 for Soul Performance. Had the 200 cel cats installed yesterday. You won't notice much of an in cab sound difference (windows up of course), but those outside said it was noticeably different. No drone, perfect if you are looking to up the PSE sound a to be turned up, but don't want your ears to ring while you are driving. You'll definitely hear the turbo's spool more too! The customer service is top notch too.

To make it louder than that? Idk, center deletes? Mike what you got? haha

Soul Performance

Hey thank you for choosing us and sharing your experience with the forum!

BMC high flow air filters may give you an ever so slight increase in sound. There's always Cat Bypass Pipes if you want it more aggressive down the line - sounds incredible IMO - but removing the cats presents fumes, a check engine light that needs to be solved, and possibly an issue with the dealership.

reacher

How are the exhaust fumes with the 200 cels? I had high flow cats on another car and the smell was unbearable, so I'm worried about doing it on this car. Especially since it's a cab. On the other hand the other car was a 6.4l American V8, so not quite apples to apples.

Soul Performance

As the video guy, I stand behind all the cars when they rev - which usually leaves me smelling and hearing worse after. We use HJS HD 200 cell catalytic converters which have a very high precious metal count to allow for high flow while still preventing check engine lights. These cats are the business. McLaren uses a similar cat (manufactured under the same roof / parent company) for their OEM catalytic converters. I don't recall smelling anything from our Sport Cats - or any application using these cats really. The Cat Bypass Pipes did have a smell.

VektorPerformance

As others have said, cats will make the more significant impact on sound levels. From observations with our own headers, we see a change in tone and a much less muddled exhaust sound. You hear/feel the pulses vs them sounding like exhaust noise. It's tough to describe, but it's a difference that is very before/after noticeable.

BulldogR6

none that I noticed. But seeing you have a cab, I think 200 cel cats would be great. Top down and hear them spool!

AutoQuest Motorsports

I've never noticed any smell with the 200cell HJS cats either