Stillen has dynoed the Sedan's dual catback exhaust system and the prototype adds surprisingly good horsepower.

Unfortunately, because it's a prototype system, the exact HP number is not yet available for release.

What I can say is... If the commerical system provides similar HP, I'll be real glad I waited!

 

Very nice! Good news!! WOOP WOOP...

have you heard this system? How does it sound in your opinion and in conjunction with other exhausts out now?

 

I haven't heard the prototype system on the Sedan.

However, Stillen's the Coupe/350Z dual catback system sounds awesome to me. The Sedan's commercial system should sound very similar.

 

sounds good. i hope it comes out soon.

 

I want to be the first. Make sure they hold the first production model for me.

It does have a dual tip, like the HKS, right?

 

Thanks for the update. It appears that Stillen has taken sedan owners seriously[img]/w3timages/icons/cool.gif[/img]

03.5 Sedan/B. Silver/Prem/Winter/Aero/Tint/Rims
69 Chevelle Hard Top BB/4.11's/Posi

 

More Sedan & Coupe exhaust system observations and opinions;

The external differences in the stock Sedan and Coupe exhaust systems are not as significant as one might think.

1 - Both the Sedan and Coupe stock exhaust systems are a single pipe design starting where the headpipes (Y-pipes) come together.

2 - The head pipe (y-pipe) are the same... the part number's are the same. (This probably includes the 350Z)

3 - The midpipes (B-pipes) overall length, inlet/outlet flange size and location, hangers, etc. appear very similar and may be fully interchangeable.

4 - The midpipes (B-pipes) resonators (pre-mufflers) are very different. The Sedan's is very large, flat, wide and (I suspect) restrictive. The Coupe's resonator appears much less restrictive. It's 60%-70% smaller and looks more like a short oblong muffler.

5 - Both the Sedan and Coupe Mufflers are a single-in, dual-out design. The Sedan's is mounted parallel to the drive train, the Coupe's transversly.

My Sedan's muffler is 13.75"L, 13.5"W, 7.75"H, with a 2.475"OD inlet and two 2.515"OD outlets. It has has a two stage feature, single out at low RPM for improved torque. (Does this really help???)

Externally the Coupe's muffler appears to be about the same size. I don't think it has the two stage feature and suspect it's less restrictive.

Much of the Sedan's missing 20HP may indeed be related to its exhaust system resonator and muffler design.

Stillen's HP gains for their dual catback Sedan prototype seems to support this opinion.

 

Thanks Dave. Good info. I've done aftermarket exhaust and intake on my SUV (may she rest in peace) and was most impressed with the performance gain. I've been watching the boards for a possible solution to the missing 20hp on the sedan and I'm betting a good deal of it is, as you say, in the exhaust. Just don't want to lose torque as I love that kick in the pants when you stomp on it. I do think the stock exhaust has nice note and revved up the VQ sounds awesome IMHO.

03.5 Sedan AT (Black-Willow-Premium-Sport-Aero-GG Grounding Kit)

 

Great news guys! Sign me up!

'03 AT Sedan | Brilliant Silver | Willow Leather | Sport | Premium | Aerokit w/Spoiler | Nav

 

As far as the difference in resonators, I am building a replacement pipe for the G sedan to replace the resonator with a straight pipe. It should be done this week or next, ( i have to borrow a welder and am still waiting on a flange.) Then in a month or so I can take it to the dyno and dyno both with and without a resonator the same day.

Sean

Better Life thru Chemistry