STILLEN 370Z Dual Cat-Back Stainless Exhaust System

LiquidZ · 03-16-2009, 08:16 AM

Quote:

Originally Posted by semtex

After I get the Stillen G3 intakes installed.

Great. Can't wait to see your results.

drisko · 03-17-2009, 09:03 PM

ANYONE KNOW HOW MUCH LIGHTER THAN STOCK THIS EXHAUST IS???

I'm really interested in it, but I was curious about the weight.

takimbe · 05-01-2009, 06:43 AM

I just got these installed at Stillen today. pics to come! Josh gave me a great tour of their facilities and I ended up making an impulse buy and I have no regrets! this is the best sounding exhaust out there!

LUVZTTZ · 05-01-2009, 11:15 AM

Has anybody done any performance testing with a GTech or something in terms of 0-60 or 1/4 mile times? I'd be curious to see effects outside of HP and Torque gains with the Stillen exhaust.

john370z · 05-08-2009, 09:45 PM

Hi all! Just had installed the Berk HFC and the Stillen cat-back exhaust. I have some comments and questions...hopefully the experts here can help me....

I think the install was done right. good cross member clearance, no obvious rattling or leaks...but

1.) There is a hiss, like a vacuum valve is opening, around 1800 rpm on the down rev
2.) The exhaust note has a inconsistent very minor clang noise under hard acceleration. I have inspected the install on a lift and cannot see any rubbing to explain the metallically clang. It is difficult to describe but it's maybe 25% of the entire exhaust note. So it is noticeable but not suicide inducing..
3.) It is very loud. If anyone is looking for a little or moderate exhaust noise increase this is probably not for you.
At full throttle it is very nice at high RPM (greater than 5k)
At partial throttle at 3K-6K RPM it sounds like you are hauling a$$ and you are not.

Question- Are you supposed to use those rubber ballencers (sp) that is bolted on to the stock exhaust? Are my experiences similar to your other experiences with similar exhaust modifications? Did you disconnect the battery to reset the ECU? How long do you expect the computer to take to make necessary adjustments?

In a perfect world I would like the exhaust note to be less raspy or metallically at times and be a little quieter at partial throttle. Love it at WOT.

Man I sound like my wife after waking up on the wrong side of the bed. Sorry for the vent. As you can tell I was expecting it to be a little more refined sounding and less audibly intrusive during regular driving at low RPM's. I hope I can get used to it and even grow to love it. Many of you have said it is A LOT LOUDER. You are right. Any comments or answers are greatly appreciated. Thanks for listening..
John

Josh@STILLEN · 05-08-2009, 10:22 PM

HFCs will introduce some rasp into the exhaust note. For some it's the sound they are looking for, for others used to a refined exhaust note, it seems shockingly apparent. HFCs will also increase the overall volume of the exhaust note. HFCs and test pipes can also have an audible (test pipes significantly more) 'hiss' under deceleration. But if you think it's beyond that, I would absolutely look for an exhaust leak. A week of driving should provide enough carbon that will appear on the exhaust for a manual inspection to root that out.

john370z · 05-09-2009, 09:31 AM

thanks josh. I'll wait a week...see if I get used to it and to see if there are any exhaust leaks. I can always put back on the cats, I'd like not to though.
john

wstar · 05-09-2009, 10:34 AM

Quote:

Originally Posted by john370z

Hi all! Just had installed the Berk HFC and the Stillen cat-back exhaust. I have some comments and questions...hopefully the experts here can help me....

I think the install was done right. good cross member clearance, no obvious rattling or leaks...but

Well that's good to hear at least

Quote:

1.) There is a hiss, like a vacuum valve is opening, around 1800 rpm on the down rev

Others have commented on the hiss, myself included. It could just be inherent in the nature of this exhaust, it could be from the Stillen intakes, or it could be an exhaust leak. It's kinda hard to tell. My car is cooling off on ramps right now to fix my exhaust leaks though, so I should be able to eliminate at least one option soon.

Quote:

2.) The exhaust note has a inconsistent very minor clang noise under hard acceleration. I have inspected the install on a lift and cannot see any rubbing to explain the metallically clang. It is difficult to describe but it's maybe 25% of the entire exhaust note. So it is noticeable but not suicide inducing..

3.) It is very loud. If anyone is looking for a little or moderate exhaust noise increase this is probably not for you.
At full throttle it is very nice at high RPM (greater than 5k)
At partial throttle at 3K-6K RPM it sounds like you are hauling a$$ and you are not.

Personally I love the nature of the sound. That sound just exudes no-nonsense raw power. When I downshift my engine sounds like a sportbike revving now (well, not quite, but it has that sort of character compared to other cars I've had in the past). If you have a leak, that could be exacerbating any rasp though. Again, shortly I'll get to see how mine is when it's leak-free.

Quote:

Question- Are you supposed to use those rubber ballencers (sp) that is bolted on to the stock exhaust?

Yes, it's in the instructions, and the Stillen unit has mounting spots for them.

Quote:

Are my experiences similar to your other experiences with similar exhaust modifications?

The main difference between you and some of the rest of us reporting on this install is that you didn't have any fitment issues clearing the crossmember, which is a good sign that either their change worked and/or the rest of us just screwed up our installs slightly

Quote:

Did you disconnect the battery to reset the ECU? How long do you expect the computer to take to make necessary adjustments?

I don't think disconnecting the battery really helps much. The car is going to learn your changes regardless, although maybe slightly slower. I don't know how long it really takes, but within a couple hundred miles I think you're pretty gtg.

Quote:

I hope I can get used to it and even grow to love it. Many of you have said it is A LOT LOUDER. You are right. Any comments or answers are greatly appreciated. Thanks for listening..

You probably will grow to love it, I have anyways. Now my neighbors on the other hand... I think they're plotting to blow up my car

john370z · 05-09-2009, 12:08 PM

Thank you so much for the feedback!

semtex · 05-09-2009, 01:15 PM

Everything you have described is normal. And fyi, if you install headers, that will smooth-out the sound and make it more refined again. I personally miss the more raw sound I had before I put the headers on. I did disconnect the battery, btw. wstar is right that your ECU will learn your mods regardless, but disconnecting the battery will expedite the process.

wstar · 05-09-2009, 05:37 PM

Re: the hissing sound, I've still got that now that my leak is fixed. I guess it's normal. Sounds kinda cool anyways

tru_Asiatik · 05-09-2009, 05:41 PM

^so we can rule off leaks then??

wstar · 05-09-2009, 05:58 PM

Quote:

Originally Posted by tru_Asiatik

^so we can rule off leaks then??

For the hissing noise, yes

If you're getting an atrocious rasp at certain RPM ranges that you hate hearing from inside the car, that might be a leak. Was in my case anyways.

tru_Asiatik · 05-09-2009, 06:06 PM

yes for the hissing noise same one that danny gt has
well i just got my exhaust installed today
im gong back to the shop in 2 weeks to see if they find any leaks

but thank you
knowing the hiss at 2.5-3k is normal kinda puts me at ease

05-01-2009, 11:15 AM	#94 (permalink)
LUVZTTZ Base Member Join Date: Apr 2009 Location: St Louis, MO Posts: 57 Drives: Black 91 TT Rep Power: 16	Street performance Has anybody done any performance testing with a GTech or something in terms of 0-60 or 1/4 mile times? I'd be curious to see effects outside of HP and Torque gains with the Stillen exhaust. Last edited by LUVZTTZ; 05-01-2009 at 07:35 PM.

05-08-2009, 09:45 PM	#95 (permalink)
john370z Base Member Join Date: Jan 2009 Location: new mexico Posts: 141 Drives: 2007 335i coupe Rep Power: 283	Hi all! Just had installed the Berk HFC and the Stillen cat-back exhaust. I have some comments and questions...hopefully the experts here can help me.... I think the install was done right. good cross member clearance, no obvious rattling or leaks...but 1.) There is a hiss, like a vacuum valve is opening, around 1800 rpm on the down rev 2.) The exhaust note has a inconsistent very minor clang noise under hard acceleration. I have inspected the install on a lift and cannot see any rubbing to explain the metallically clang. It is difficult to describe but it's maybe 25% of the entire exhaust note. So it is noticeable but not suicide inducing.. 3.) It is very loud. If anyone is looking for a little or moderate exhaust noise increase this is probably not for you. At full throttle it is very nice at high RPM (greater than 5k) At partial throttle at 3K-6K RPM it sounds like you are hauling a$$ and you are not. Question- Are you supposed to use those rubber ballencers (sp) that is bolted on to the stock exhaust? Are my experiences similar to your other experiences with similar exhaust modifications? Did you disconnect the battery to reset the ECU? How long do you expect the computer to take to make necessary adjustments? In a perfect world I would like the exhaust note to be less raspy or metallically at times and be a little quieter at partial throttle. Love it at WOT. Man I sound like my wife after waking up on the wrong side of the bed. Sorry for the vent. As you can tell I was expecting it to be a little more refined sounding and less audibly intrusive during regular driving at low RPM's. I hope I can get used to it and even grow to love it. Many of you have said it is A LOT LOUDER. You are right. Any comments or answers are greatly appreciated. Thanks for listening.. John Last edited by john370z; 05-08-2009 at 09:47 PM. Reason: forgot stuff

05-09-2009, 01:15 PM	#100 (permalink)
semtex A True Z Fanatic Join Date: Jan 2009 Location: Behind enemy lines Age: 53 Posts: 5,995 Drives: People to drink Rep Power: 32	Everything you have described is normal. And fyi, if you install headers, that will smooth-out the sound and make it more refined again. I personally miss the more raw sound I had before I put the headers on. I did disconnect the battery, btw. wstar is right that your ECU will learn your mods regardless, but disconnecting the battery will expedite the process. __________________ "There are no small accidents on this circuit." -- Ayrton Senna 316.8whp & 248 ft/lbs (Dyno Dynamics) \| 319whp & 256 ft/lbs (DynoJet) (04/23/10) Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.

05-09-2009, 05:37 PM	#101 (permalink)
wstar A True Z Fanatic Join Date: Mar 2009 Location: Houston, TX Posts: 4,024 Drives: too slow Rep Power: 3594	Re: the hissing sound, I've still got that now that my leak is fixed. I guess it's normal. Sounds kinda cool anyways __________________ 7AT Track Car! Journal thread / Car setup details

05-09-2009, 05:41 PM	#102 (permalink)
tru_Asiatik Track Member Join Date: Feb 2009 Location: so cal Posts: 793 Drives: 2009 370Z 6MT Rep Power: 270	^so we can rule off leaks then?? __________________ Stillen G3 CAIStillen CBEBerk's HFCEibach ProkitHotchkis Swaysichiba 15/20mm spacers? Oil coolerStillen PulleyStillen Headers Last edited by tru_Asiatik; 05-09-2009 at 05:47 PM.

03-17-2009, 09:03 PM	#92 (permalink)
drisko Base Member Join Date: Jan 2009 Location: So Cal Age: 43 Posts: 160 Drives: 09 370Z PW Tour S 6M Rep Power: 16	ANYONE KNOW HOW MUCH LIGHTER THAN STOCK THIS EXHAUST IS??? I'm really interested in it, but I was curious about the weight.

05-01-2009, 06:43 AM	#93 (permalink)
takimbe Base Member Join Date: Feb 2009 Location: San Diego, CA Posts: 223 Drives: 09' PG 370Z w/SP Rep Power: 264	I just got these installed at Stillen today. pics to come! Josh gave me a great tour of their facilities and I ended up making an impulse buy and I have no regrets! this is the best sounding exhaust out there!

05-08-2009, 10:22 PM	#96 (permalink)
Josh@STILLEN The370Z.com Sponsor Join Date: Dec 2008 Location: Costa Mesa, CA Posts: 1,197 Drives: 2004 G35 Coupe 6MT Rep Power: 533	HFCs will introduce some rasp into the exhaust note. For some it's the sound they are looking for, for others used to a refined exhaust note, it seems shockingly apparent. HFCs will also increase the overall volume of the exhaust note. HFCs and test pipes can also have an audible (test pipes significantly more) 'hiss' under deceleration. But if you think it's beyond that, I would absolutely look for an exhaust leak. A week of driving should provide enough carbon that will appear on the exhaust for a manual inspection to root that out.

05-09-2009, 09:31 AM	#97 (permalink)
john370z Base Member Join Date: Jan 2009 Location: new mexico Posts: 141 Drives: 2007 335i coupe Rep Power: 283	thanks josh. I'll wait a week...see if I get used to it and to see if there are any exhaust leaks. I can always put back on the cats, I'd like not to though. john

05-09-2009, 12:08 PM	#99 (permalink)
john370z Base Member Join Date: Jan 2009 Location: new mexico Posts: 141 Drives: 2007 335i coupe Rep Power: 283	Thank you so much for the feedback!

05-09-2009, 06:06 PM	#104 (permalink)
tru_Asiatik Track Member Join Date: Feb 2009 Location: so cal Posts: 793 Drives: 2009 370Z 6MT Rep Power: 270	yes for the hissing noise same one that danny gt has well i just got my exhaust installed today im gong back to the shop in 2 weeks to see if they find any leaks but thank you knowing the hiss at 2.5-3k is normal kinda puts me at ease __________________ Stillen G3 CAIStillen CBEBerk's HFCEibach ProkitHotchkis Swaysichiba 15/20mm spacers? Oil coolerStillen PulleyStillen Headers

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