Need Information about the 2.5" muffler in the TurboXS Stage #1 kit plz

[WRXMod]

2.5" Stainless Steel Muffler (all SS construction including flange and hangers)

Anybody have any info about this? I'm curious why TurboXS included this in their package. I'm by no means knocking the choice to include this, but rather am curious what performance gain this is going to provide. I can't seem to load the pictures from their website,... is this muffler actually include a downpipe from the last catalyst? Aka a catback exhaust?

Thanks!

PS - Did many searches on TurboXS kit but found nothing mentioning the exhaust

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[WRXMod]

Maybe the TurboXS vendor could answer this one - bump

[nmyeti]

I am running the muffler from turboxs, so i will comment on this, and mark can step in and add his as well if he sees it.

1. Its the muffler section only, and it bolts to the rear of the stock center section

2. It is a bit less restrictive than stock. it runs a bigger pipe than the stock, and if you look at the stock setup just past the connector it necks down even more.

3. It sounds great! Mark knows that many people want a bit more of an agressive sound without being anywhere near loud, and so he has thrown it in with his stage 1.

4. When the time comes, it will bolt right up to their full exhaust system.


I am running this muffler with a scoobysports downpipe and center sections.

Its quite nice! Give mark a call, as i think he starts shipping stage 1 kits yesterday and today.

[TurboXS]

We haven't really started selling our mufflers yet and we only have a handful out there which is why you haven't seen much on the i-club. We're kind of strange in that we like to have products actually on the shelf ready for shipping when we announce that they are available for sale.

Here's an excerpt from an e-mail I sent this morning to someone named "Evilseed" regarding this topic. I'm pretty sure "Evilseed" is aka "WRXMod":

Dear Mr. Evilseed, (sorry, I couldn't resist!)

The muffler is not really cat-back as it does not replace the last mid-pipe with the resonator (it bolts to it). It made ~3hp at the wheels when we bolted it on in place of the stock muffler. The main reasons behind it are:
1. It flows better than stock (not so important for Stage 1 but will be in Stage 2 and 3)
2. You can actually hear your car with it and frankly, it makes it sound faster. It's not obnoxiously loud. Just a nice boxer "burble" at idle and low rpms. As you increase revs, engine noise takes over. At highway cruise speed, road noise is much more pronounced than the exhaust.

Mark
TurboXS

PS - We have been having intermittant e-mail server failures today so I apologize if any of you are trying to reach me by e-mail.

[TurboRex]

Can anyone post a picture of this muffler either on or off the car? Thanks.

[viodea]

Does anyone has a sound clips of this? I want to hear how it sound before I get it.

[WRXThis]

Why is this muffler piping only 2.5"? Isn't the norm for most aftermarket exhausts on the WRX 3"? I wonder if there complete turbo back system will be 2.5" to match the muffler, or if they will go up to 3" piping. TurboXS explain why you went with this please.

[nmyeti]

The norm is not 3 inches. 3 inches will flow much more gas than you need to on our motors unless you are looking for 400+ hp. In the DSM world (similar motor with similar flow requirements) you can run low 11s on a 2.5 inch kit.

Corkey Bell will tell you that 2.5 is plenty of area for what we have.

BPM uses 3 inch, and i have actually seen some reports of them loosing torque down low because of the loss of exahust scavenging.

I am running a 2.5 inch from the downpipe back (scoobysports down pipe starts out at 3 inch and tapers to 2.5 at the end) and just ran 13.5@99.9 on only my second run down the track ever in my WRX. I think i could have hit 13.2 or so when the weather cooled a bit... Oh ya this was at 3600 feet on a hot and 100% humid day.

Mark will tell you that he used 2.5 inch so that he could keep the noise down. It works quite well. The muffler sounds very nice.

-Nathan

[WRXThis]

When I say the norm I mean most all of the aftermarket systems out already are 3". He went with a 2.5" pipe to keep the noise down? IMHO to keep the noise down you are restricting airflow therefore you are loosing power. What about the people that want a loud WRX like me? Oh ya, I hope he also has an option for a race exhaust with no cats.

[nmyeti]

I think your missing the point. 3 inch can actually hurt you since you are slowing the exhaust gas down. There is no extra harmful restriction that is going to be added by 2.5 inch muffler. The turboxs muffler flows great. I am running a totally cat-less system on my car and it works quite well. I know we all think bigger is better in most cases, but a well tuned 2.5 inch system will outperform a 3 in a lot of situations. If you want 400+ hp you may need to run a different system.

Check out this dyno of a scoobysports (said to be the best full exhaust you can buy in the UK where they have had the WRX for quite some time)



for more information see
http://dyno.scoobynet.co.uk/uk/01_ba...ullexhaust.htm


Then read the auto speed article where they dyno the improvement in a WRX with an APS 3 inch system. They got NO power gains with it. Strange don't you think?
http://www.autospeed.com/A_1054/page1.html

[JaMa]

I have to stand behind nmyeti and TurboXS in this instance. There have been many, many tests of exhaust systems for the WRX since its inception in the mid-90s in the UK and the 2.5 inch system has always been the way to go if you want to make power. 3 inches is just too much room and exhaust gases swell and slow down the overall effectiveness of the system

I have spoken with a number of tuners in the UK and Europe who have 350-390hp cars with 2.5 inch exhaust systems, dyno proven. Plus, we all know the transmission limits of this car are somewhere around 300hp so if you are running much more than that you are asking for a big repair bill.

So, I guess my point is: demand proof. Dont go out and buy a 3 inch exhuast system just because someone says it will make power: get a dyno plot and see for yourself. I did, and I discovered that the 2.5 inch boys like Scoobysport and Stromung immediately come back with documented results. I emailed MRT, BPM, and several other vendors of the 3 inch turbo back systems asking for dyno plots of their systems on stock or slightly modified cars with baselines and modified power. NOT ONE of them responded, which leads me to believe they dont really know what their systems do.

So, I run a 2.5 inch system because I want performance, not bragging rights to an extra 1/2 inch of pipe.

Cheers

JaMa

[WRXThis]

Oh I get your point just fine Nmyeti, I speak the English language very well. I just find it amusing that aftermarket companies would produce a 3" exhaust that would actually cause us to loose power instead of gaining it. It's usually give or take with power. Either you gain some high end and loose low end power or you gain low end and loose some high end power. I would give up some torque to gain some high end power in my WRX. IMHO with the 3" pipe you will have more high end power and the 2.5" will give you more low end power. The 2.5" and 3" pipe has been debated on here for sometime. I won't believe a thing until I see dyno results of both sizes measured then that will put a rest to this debate.

[JaMa]

A while back, I made an appeal to vendors on this forum to put their money where their mouth is. No one responded.

I am soon to have a 2.5 inch turbo-back system with 1 cat.

Here's the deal: If any vendor wants to send me a 3 inch turbo back WRX exhaust system, i will personally take both systems to the dyno and, out of my own pocket, prove once and for all which one is the best to go with to make the most power with reasonable modifications. (turboxs chip and intake mod)

I would love to do this, but I dont really need or want a 3 inch system personally and I am not willing to shell out $1200 or more on a system to test. But, the offer still stands to any vendor who wants to take the challenge.

JaMa

[nmyeti]

Originally posted by WRXThis
Oh I get your point just fine Nmyeti, I speak the English laguage very well. I just find it amusing that aftermarket companies would produce a 3" exhaust that would actually cause us to loose power instead of gaining it. It's usually give or take with power. Either you gain some high end and loose low end power or you gain low end and loose some high end power. I would give up some torque to gain some high end power in my WRX. IMHO with the 3" pipe you will have more high end power and the 2.5" will give you more low end power. The 2.5" and 3" pipe has been debated on here for sometime. I won't believe a thing until I see dyno results of both sizes measured then that will put a rest to this debate.

Man, i didn't mean any disrespect when i said that, but i wanted to be sure that we were clear on the bit about 3 inch exhaust acutually hurting power.

Here is the thing, yes it is a trade off, but at the top end your not really gaining anything with a 3 inch exhaust until you go over 400hp. You see up to that point the single largest restriction in your exhaust system is going to be in the form of a turbine housing and wheel. Thats why 3 inch systems don't produce any real gains over the 2.5 inch system. They are too large to keep velocity up for scavenging in the low end, and are not really making a real difference on the big end without a very large turbo on the car.

If you want to run a HUGE turbo, and make more than 400+ hp, the exhaust flow requirements are going to say that you need a 3 inch pipe. If not, you can actually gain torque and power by staying with a well tuned 2.5 inch pipe.

You have to choose what fits your needs, but if i were you i would stay up late one nite and call scoobysports in the UK, or talk to Ken at www.rallyperformance.com and see what he has to say. Their system time and time again has been proven to be the best you can buy for dyno number AND real world drivablilty. Ask them "why?" wnd they will tell you.

I look forward to getting some more numbers on the 2.5 inch vs 3.0 inch issue soon, but the two links i posted above can be quite instructive.



here is the dyno of the APS system vs stock. Throw the numbers out the window because they are on a different dyno, but look at the difference in the curve.

here again is the scoobysports curve... i'll make it easy and put them next to each other



-Nathan

[WRXThis]

What an offer Jama has extended. I could even join him at the dyno. I hope someone will step up to the challenge to put this debate to rest. No hard feelings Nmyeti.

[nmyeti]

Originally posted by WRXThis
What an offer Jama has extended. I could even join him at the dyno. I hope someone will step up to the challenge to put this debate to rest. No hard feelings Nmyeti.

Its cool, i understand its hard to read people when your reading text.

No problem.

-Nathan

[speedbuggy67]

What ever happened to this dyno test did I miss it or did all the company's chicken out. I want a cat-back at least and I was almost sold on the cobb 3in system but I am having second thoughts now. I don't want anything toooooooo loud but the stromung sounds accectable. Anyone else on that?

Scott

[speedbuggy67]

What ever happened to this dyno test did I miss it or did all the company's chicken out. I want a cat-back at least and I was almost sold on the cobb 3in system but I am having second thoughts now. I don't want anything toooooooo loud but the stromung sounds accectable. Anyone else on that? I am not swapping turbo's or intercoolers just prolly the turboxs chip. I figured buying the cat back would be better than the turboxs axle back.

Scott

[speedbuggy67]

ttt

[GTBGUY]

JaMa - Is Nate rescheduling the dyno pulls on WRXThis' car? Since you've got the P'N'P TurboXS Unichip, why don't you go up against WRXThis' car equiped w/ the Brullen Turbo-back? You could easily pull your Unichip to do base-line runs (for both cars), then do runs w/ the Unichip with your WRX and WRXThis'. I up to the challenge, but as of yet, I've had no definate word on the Dynoday.

[TurbosOnly]

I have the 3" BPM GT with the removable silencer. The silencer is about 2 1/2". Wouldn't you get the same performance gains as any other 2 1/2" exhaust with the silencer in? I have noticed a great improvement in performance but cannot notice a difference w/ or w/o the silencer in. Maybe a trip to the track will tell.