Hey, I was looking into this mod. Anyone have this done already on their car? I already have the dual stillen catback, and I was thinking of throwing the headers and race pipes on with kinetix high flow cats on to complete my exhaust system...

Any suggestions on this setup?

 

The Stillen "race" pipes replace the cats so no need for the kinetix high flows. I have the Stillen pipes with borla headers and exhaust and they are sweet! A little raspy but noticeable gains.

 

...and though there is a noticeable gain, an ECU tune (dyno tune if available) is requried to maximize performance. As for the rasp, don't be fooled, the 'resonated' test pipes sold by Stillen do nothing to quiet it. If you can live with, no worries. If not, go for the Crawford cats. BTW, ECU tuning helped quiet the rasp a bit...now I only have problems at WOT.

-Rich

 

So then would the Stillen full setup give more power gains than the stillen headers + kinetix HF cats combo?

Second- if I go with the full stillen setup, is there any other mods I can do (besides ECU) that can help the sound?

 

Where has anyone heard that the stillen race pipe are designed to reduce noise? As far as I know and have been told from stillen they do not claim their race pipe design reduces resonance. Here's the qoute from stillen's website "Contributing to the performance gains along with the straight-through free-flowing design, is an expansion chamber that promotes more efficient exhaust scavenging." Sounds like to me that the "expansion chamber" is strictly a performance function and not a sound supression function.

 

Hmm. Im not sure which mod I want to go with. I like the Stillen headers, but Im not sure if I want to go with the Stillen race pipes or the Kinetix HF cats; Ive heard good things about both of them. Basically, I want to get the most performance that I can out of my exhaust system while still having a good sound to it... Anyone have feedback?

 

I have the race pipes with the Stillen exhaust and love the top end power. I will be doing the headers next, then the reflash.

The race pipes will give you better power than hi-flows but they are louder.

Go with the max power, you wont regret it.

 

Do headers alone increase sound when keeping stock cats?

 

Yes, I had a Borla exhaust on for a while, now I have headers, but I haven't replaced the cats yet, it got louder.

 

I am going to do this set of mods real soon; I used to have a Stillen eXhaust, but now I have the stock one on my Z (long story)....

#1 Is there any reason why it is preferable to stick with a stillen exhaust/header combo over a stillen exhaust with Borla headers? THe Borla headers are quite a bit cheaper.

#2 Those of you with the race pipes - any trouble with legalities? I know you can't pass emissions with those - what do you do? What about the headers? Are the ones by Stillen street legal? How do I find out in my state?

#3 So the race pipes/headers change the sound of just the stillen exhaust alone? Does it just make it louder or does it alter it completely?

Thanks!

 

Well, I am not an expert in this topic, but I guess I can throw in my .02

#1 as far as staying with just Stillen instead of mixing and matching, I dont think it makes much of a difference. I was the one that started this thread saying that I was going to go with Stillen headers + race pipe to complement my exhaust, and now 2 months later I ended up getting Crawfords instead. Its really a balance of price, performance, sound, and reputation on these products.

#2 I have heard of quite a few people getting into crap for test pipes, even some stories of cars getting impounded for not having cats on them. This was one of the main factors that made me decide to go with HF cats over test pipes. Also, I have heard that test pipes give a loud and raspy noise as opposed to HF cats, which complement catbacks well. On a positive note for test pipes though, they do give a much bigger HP gain than HF cats. I guess it depends what is more important to you, power or sound. I know that Kinetix makes "resonated" test pipes which is supposed to be a hybrid of the two.

#3 it doesnt alter only the stillen exhaust, it would alter whatever catback exhaust you hooked it up to, even the stock one. HF cats would add a deeper pitch to the exhaust, while race/test pipes would add a louder, kind of raspy noise to it.

 

The z has good sound insulation...if you want horsepower nothing beats the straight pipes...end of story...the sound is really negligible unless WOT...and anyways then you will want to hear the thing...just my 2 cents...that how it was with my audi s4 straight through all the way...a bit louder but worth the HORSEPOwer

 

I have Stillen race pipes and exhaust. They're not as loud as you think when you're just cruzin around. When you go WOT, it will give a deep roar in a good way.