4ocious

I own an 11 CTT (958) that's been great so far. I'm thinking of replacing my secondary cats to increase the hp/tq and pump-up the sound. I did the same thing on my 10 CGTS and "thought" I noticed and felt a difference, but it was hard to tell. I previously bought Fab Speed pipes and had nothing but trouble with them hitting/vibrating the sub-frame on start-up.

Now that I'm driving an 11 CTT what noticeable difference will I hear and feel? And, is it worth the expense or will I encounter the same problems I had with my CGTS?

docwyte

From what I gather it's mostly a mod for sound. Which is why I can't justify paying $500 for the HHR pipes or even more for the Fabspeed ones.

I'm waiting for a used set to pop up, then I'll get em.

fatmatt0116

I took my 958 TTS to a local exhaust shop and had them do it. It was $120 and it's custom welded so there is no rattle ever. It's nonsense to pay $750 for the pre-fab bypass. At the $120 price point you can have it done and decide for yourself whether you like it. I was quoted $60 to reverse it, so worst case you're out about $200 if you don't like it.

I do like the sound. It is substantial but there is no drone. The mod is at it's best when you up shift during acceleration -- it's great.

hahnmgh63

When someone says is it worth it I say that's subjective. Would I do it again...yes. Probably is a Dyno measured power increase. I usually take anyone's claims and divide it in half and round down. They do sound better, technically they should help the Turbos spool up faster with the lessened back pressure but all small amounts. So a slightly better sound and slightly more power/spool up yes. I would do it again but would probably shop around some more or spend the time and do it (fabrication) myself (just got a new Mig Welder).
P.S. I have the Fabspeed on my '06 CTTS and they fit very well, no hitting/vibrating. Maybe I got a later improved set. I installed them about 3yrs ago.

4ocious

Thanks and I agree with your comments. My vibration problem was limited to the left side hangar. It was a known problem at the time that FS acknowledged and failed to fix. Only after many more complaints did they take action to correct it.

DWPC

I'd only add is that doing that to a fairly new car may bite you when you want to trade it in or sell. Won't pass smog for registration in any state that tests.

8202632

I'll chime in with my 2 cents. I went with fabspeed after researching this thoroughly. My reasons are below. I first did my Cayenne CTTS and then also replaced my center exhaust on my Carrera S with the Fabspeed x pipes.

I went only for sound. Any performance gains/improved drivability was purely icing on the cake.
In Memphis, there are not many shops that will touch an exhaust system due to liability. Since this was the case, I wanted to purchase something that would bolt on directly. A local Mercedes shop did the install and did not have to remanufacture anything. So for me, it was about having something fit right out of the box and something that came with a lifetime warranty. If I could even find a shop that would do the mod, I'm not sure I would trust them to create something that might fail in a month, year, or few years.

To me it was worth the extra cost for the convenience of it fitting right out of the box, and I'm happy with the increased aggressiveness of the sound. Fabspeed was able to answer my questions, provide a warranty, and has several customers that were happy with the product.

In the end, it's all about what gives you peace of mind. Cheapest is not always best, nor is most expensive. It's all about where you derive value from a transaction. Hope this helps!

pdxjim

I went with the Fabspeed on my 05 and 09 CTT's. Could not get a muffler shop to touch them. Had my race car mechanic install them and remove upon sale. Liked the sound and never had any rattling problems. Passed our state DEQ tests when it was time for license renewal.

BlazinPond

I installed Fabspeed Secondary Cat bypass pipes on my 958 CTT.
Love it. I get compliments all the time and quite happy with this mod.

Check out my DIY i posted over on 6speed...

http://www.6speedonline.com/forums/c...l-success.html

69gaugeman

Depends on what you call testing. The secondary cats are an insurance policy for some very specific conditions where the fuel is rich and the primary cats may not be able to cope. (hard acceleration with cold engine for instance). During regular hot running they do NOTHING. Which is the state that any dynamic testing is done in. In places like where I live, The ECU does the testing. If the check engine light is off and all the tests completed (confirmed by just plugging in the OBDII) then it passes. No need for secondary cats at all.

John@Fabspeed

Same for us here in PA. You would still pass a sniffer test as well with the secondary pipes.

We have long since fixed any rattling issues with the pipes and they are selling as good as ever!

FYI, I have three sets in stock!

BG305

I think it's worth uncorking the CTT. Here's what mine sounds like with a 3" turbo back Xpipe.

primm907

Just got mine finished up on the GTS. Went with HHR, and spoke with Hank a couple of times during the purchase process. Also added their intake. Apologies for the crappy iphone video...

North Shore 911

Reviving this thread as I'm looking for advice on waking up my 2012 Cayenne S's V8 exhaust note. Given that the bypass pipes are fairly basic, is there much difference between the Fabspeed and the HHR pipes? Wtih a price difference of $200 I'm hard-pressed to understand the need for the additional cash for what are pretty similar flow-through pipes (and the clips I've seen for both seem to add a really nice growl )

I'm a BIG fan of the Fabspeed Sport Headers and 200-cell cats that I installed on my 2010 Carerra 4S Cab, but I'm not planning on any other exhaust mods on my Cayenne S. Any thoughts for a brother looking for best value on an enhanced Cayenne S exhaust note....?

1FlossedM3

Fabspeed makes a great product, I'd spend the extra money on quality secondary pipes. The rattling would bother me but it seems Fabspeed has cleared that up.

Fabspeed also claims 17whp over stock?