I'm confused I thought that the stillen catback had a y-pipe design while the invidia is the only one I know of with an x-pipe.

The shape of the design on the center section of the exhaust has been a selling point for a lot of manufacturers, and there can be benefits for different types, y / x / h / true dual.. such as you've seen introduced..

Ultimately theory on exhaust succeeds or breaks down at one significant point, and that's the final result.. The only exacting method to extract the most horsepower from a particular vehicle is relentless testing of various configurations for an exact vehicle, applying the theory and knowledge of the engineers involved and experience.

There are a variety of reasons that consumers purchase exhaust systems. Some are looking for performance, some sound (whether reserved or extreme), some the final look (bling) aspect.. it's a very personal choice. It's the same reason we manufacture our own and carry other mfg exhaust systems. You do have choices.

STILLEN has gone down the path of maximum performance, with a strong and aggressive increase on the factory exhaust tone, without the aspects of drone and an overly loud system.

Performance gains have been independently proven as dramatic, transforming a stock 370Z with its installation alone, and allowing for incremental gains from other improvements such as the Gen 3 Intakes, HFCs, etc.

We, after exhaustive testing (including y/x/h-pipe), configured our exhaust as it exists now, including subtle changes in piping sizes, center section, muffler design, etc.

Every piece of an exhaust system can have an effect on performance and sound, and any exhaust mfg should take all of these into consideration, and put the vehicle on the dyno and do performance / sound level / quality testing to ensure all goals are achieved.

I hope that helps explain our process for development and choice of design elements within the exhaust, and to realize that all things must be considered, especially in light of some jargon regarding exhausts principles that is often brought up.

Semtex,

I'm wondering how you like your Stillen CBE at this point. There is a lot of hype online about these newer offerings but I think the Stillen is still a great option.

I'm in the market for a CBE and I still think the Stillen option is the way to go. Just a few questions...

1) Have you noticed any drone at all with the Stillen CBE alone (think this was your first bolt-on, no?). What RPM ranges seem to be troublesome if you do notice drone?

2) How about drone with the Berk HFCs?

The combo seems to play 'nice' together and the sound also compliments each other from the videos.

Do you think the Stillen CBE alone is a nice sound upgrade to the stock tone? I love the aggressive, low sound of the FI exhaust, but I won't compromise for a droning interior. Also, the Stillen exhaust has a nice rebate now.

Thanks,

-Alex

You know, it's funny you should ask, because just yesterday I was driving and thinking to myself how pleased I am with this setup. I was actually considering swapping for FI's CBE at one point, but I'm now of the opinion that things are just fine the way they are (not that I think anything is wrong with FI's CBE, mind you). It's been raining pretty heavily in my area this week, so traffic has been a little thicker and slower than I usually have to deal with. I work from home, so I usually only go out during off-peak hours and don't have to deal with slow traffic. This past week though, I'd typically get stuck behind cars going around 40mph, and every now and then things would open up and I was able to nail it. What this made me realize is how quiet the Stillen CBE can be (even when combined with Berk HFCs) when I'm just taking it easy and being gentle on the throttle. As soon as I get into it, however, the exhaust note just comes alive! I also noticed that when driving around at slow speeds, even though the exhaust is pretty quiet, I get a really nice 'burble' every time I downshift. Point being, the exhaust can still sound aggressive without being loud. Every time I hear that burble it's as if the car is saying 'I'm waiting . . . I'm waiting . . . c'mon, unleash me already!' And that just makes it all the better when a gap opens up and I dip into the throttle!

Anyway, let me address your specific question about drone. Now, one thing to be aware of is that I put the Stillen CBE and Berk HFCs on together at the same time, so I have no first-hand experience of the car with just the CBE only. Having said that, I do not detect any drone from this setup at all. Drone can be a tricky thing though. What I mean by this is that I think whether or not a setup drones is somewhat subjective and dependent on individual perception. What one person considers to be normal, or even pleasant-sounding, another person might consider to be drone. To someone who has never modded their cars before, for example, my car might 'drone' to them. And all too often, I see people discussing drone without defining what, to them, qualifies as 'drone'. So let me take a sec to define for you what I consider to be drone. To me, drone is when an exhaust note hits a certain frequency that actually causes vibration that can be felt -- felt through the body panels, the interior, your skull, etc. I once had an S2000 with an HKS Hi-Power exhaust, and that sucker droned. At certain rpm ranges, it'd feel like my skull was vibrating. I actually got headaches if I drove in that thing for too long at those rpm ranges. So that's what I mean by drone -- it goes beyond something sounding loud; for me it has to do with frequency and vibration. And defined as such, my current setup does not drone, EVER.

While we're on the topic of sound, let's talk about rasp. I define rasp as when an exhaust emits a 'rattling tin-can' type of sound. It sounds hollow and metallic. Defined as such, this setup has just a slight touch of rasp around 2500 rpm. It's very subtle, so subtle that I actually have to listen for it, otherwise I don't even notice it.

Hope that helps! Let me know if you need more detail.

Thanks for the great reply. I too consider drone to be the panel rattling, ear pounding, head shattering resonant frequency. Loud and drone are absolutely different.

I'm glad to hear the Stillen/Berk setup is drone free. The only extra question I have is how the sound differs from stock at idle and normal cruise. Do you and local bystanders know you have an aftermarket exhaust or is it completely under the radar in these ranges? I love that it comes alive with throttle, but I want to know it's there ALL the time :).

I may be placing my order very soon!

Yeah, you can tell at idle. It's deeper. But it's not an intrusive 'hey everyone look at me!' kind of sound, if you know what I mean. In fact, all you need to is replay this video and listen to how it sounds before I start revving to get a sense of what it sounds like at idle.



Not sure if anyone notices when I'm just cruising, though. I've never stopped to ask! ;)

Just to follow up on this thread and as many may already know...I bought the Stillen CBE (no HFCs). It's a great sounding exhaust that for me is the perfect level of loudness without being intrusive. As Semtex stated, at idle it's a low growl that you'll identify as 'not stock' but it's not in your face. On the other hand, it opens up really nicely into a loud roar at WOT. Agreed that it's not quiet as the exhaust note set off a car alarm yesterday while I was going through the garage at 3k RPM :). No drone or rasp at all, but this is sans HFCs.

Love this exhaust! I'm amazed it's not getting more attention, but perhaps people just move on to the 'next' thing too soon.

Did you ever find a place to dyno your car? Maybe you posted it in another thread?