Nikolov

It's not a bad idea, it's just that Kline make the equal length headers for OEM turbos flange only and most guys running 76mm exhaust are running larger turbos.

CodyzWorld

why not run stock or hi-flow cats?

before people start laughing, I live in Cali, got reff'ed once in my other car, what a pain in the A$$ that was. Too old to deal with this smog crap.

onfireTTS

I have the Inconel Kline 2.50” system with 100 cell cats. Zero cell, zero smell, zero drone.

John D II

Tried all the sizes and IMO, 2.5 with 100 cell cats is the answer. Our 991TT 2.5 X-Pipe with 100 cell cats and OEM tips has no drone and sounds phenomenal. The straight X-Pipe with 100 cell cats lets some great sound out and the 2.5" piping keeps the sound level moderate with no drone. Great high RPM sound, too. It's what I am running and I find it perfect.

rodsky

I have Kline SS headers and exhaust and have no drone - or none that I have noticed in coming up on 3 years

pfbz

991 Turbo exhausts are tricky to get right. Couple that with the fact that "right" means different things to different owners... And 991.1 and 991.2 Turbo exhausts, while nearly identical (tips are different), can SOUND quite a bit different due to different ECU Sport+ programming .1 vs .2.

I am now on my SIXTH exhaust system permutation with my 991.1 Turbo S, and my buddy is on his fourth with his 991.2 Turbo S, plus another local buddy who also has a Turbo S with yet another combo. One has settled on a Kline Euro with stock cats. Definitely no drone, way better than stock, still not enough volume and full throttle "wail" for me. One has settled on a Kline with sport cats. Good sound, but too much decel burble/pop noise (see below).

My two best combos were stock exhaust with cat bypass (really good actually, and obviously one of the least expensive solutions) and the Soul Performance with stock cats.

But my favorite* combo for on-full-throttle sound was the Soul with cat bypasses... Absolutely lovely sound, not obnoxious at all in my opinion, exactly what I was looking for!

* Until I drop the throttle! Then Porsche's 'built in' decel burbles and pops come on really loud, and the volume of the pops is just way too much. This is a bit more of a problem in the 991.1 Turbo S vs. the 991.2 Turbo S, as Porsche mellowed out the decel pops a bit on the later cars and eliminated the added burble/pop completely in Sport+ mode while it comes on full force in the .1.

The decel pops/burbles can be dialed out with a custom Cobb tune, which would make the catless Soul perfect again, but I already have a JB4 tune which I'm pretty happy with, and the price tag for replacing it with a Cobb tuner and custom tune is just a bit hard to swallow vs. just going back to a catted system. I might also try sport cats, but again, they are pretty pricey for a solution that I might or might not like...

Bottom line? Don't trust anyone's opinion of what sounds best. Don't trust youtube videos. Either bite the bullet and buy what you think might work, try it, and sell it if your not happy or try and get to ride/drive in a similar car with an exhaust you're considering and decide for yourself.

Here are the combos...

My Combos. All .1 Turbo S, All Stock Tips

1. Stock exhaust, stock cats = Too quiet!
2. Stock exhaust, cat bypass = Pretty good! No drone, I wanted even bit more volume and had trouble getting back to as good as this. I'll give it an easy 7.
3. Sharkworks race, stock cats = Not as good #2. Tone was a bit off, volume suprisingly quiet considering they were effectively straight crossover pipes.
4. Sharkworks race, cat bypass = Holy hell was this terrible! Not just as in too loud, but sounded completely "off", like a badly out of tune instrument.
5. Soul, cat bypass = Exactly what I was looking for! Great power on wail, not too loud, not droney. **UNTIL** you chop the throttle and the pops sound like a pistol shot.
6. Soul, stock cats = My current favorite, though too still too quiet for me. No obnoxious burble/pops however. I'm not sure if I like this better than combo #2 honestly, been too many other in between.

Other combos, Local Turbo S cars, plenty of personal seat time. seat time. Both .2.

1. Stock cats, stock exhaust = Too quiet!
2. Soul, stock cats = See #6 above, sounds pretty much the same since the decel burbles and Sport+ mode aren't an issue.
3. Kline Euro, stock cats = My friends current and favorite setup. Still a bit too quiet for me.
4. Kline, sport cats = Other friends current setup. Not bad, but has the same problem as my catless Soul, though not quite as obnoxious.

The plus side of trying all these combos? I'm getting pretty damn good at swapping exhausts, cats, bypasses, tips, and 02 sensor extenders!

cosmo1

The stock exhaust was too quiet for so I went with the Tubi Exhaust with 200 sport cats. It was ok but to me sounded like an outboard motor. Than I decided on kline 76/70 race exhaust with dp's and drone between 2000-2500. I'm contemplating trying the kline ss even length headers to see if it may deafen the drone at that specific rpm or just sell my exhaust and try the 70mm kline exhaust.
Hey thank you all for the valuable feedback.

Pb Pedis

I’m confused… you said in your first post that you have the 3” Kline setup…wouldn’t that be the 76/76 race version? I have the “regular” 76/70 stainless steel and no drone with decat pipes on stock 991.2 TTS turbos. Just want to make sure we are comparing apples to apples here.

cosmo1

I have the 76/70, my apologies for the confusion.

Penn4S

The few Europipe comments are right on. I’m on my 3rd EP, the previous 2 were on different generation TT’s, and the sound is awesome and no perceptible drone. I also had a Kline Iconel on a previous 991.1 4S which was also amazing. No experience with Kline on my TTS.

cosmo1

Which Kline Exhaust do you have currently?