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Discussion Starter · #1 · (Edited)
I'm trying to decide between these two for a turbo back system. Anyone care to comment as to the differences in performance, sound, quality, etc.?

Also, anyone know any differences between the Magnaflow axle-back that comes with the TurboXS vs. the Prodrive axle-back?
 

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i don't remember all the differences from when i was researaching this, but i went with the MRT, and am very pleased...
 

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BlueScoob - If you want to have maximal choices in terms of tip styles as well as acoustic preferences, you might want to consider the iON/Brullen turbo-backs for your WRX.

Otherwise, you could always go with a TXS down-pipe and then run iON/Brullen's TXS adapted cat section with the iON/Brullen cat-back. This will give you 3" piping all the way through at the cat.

Contact iON for more info -> [email protected]
 

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Discussion Starter · #7 ·
Thanks for the replies, guys. I also wanted to ask that I noticed the TurboXS system goes to 2.5" right before the axle-back. I come from the Honda world where FI apps had 3" all the way through the muffler. Do some of the other turbo backs mentioned have full 3", and will this make a difference on the WRX?
 

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the thought is that as the exhaust gas travels through the dp and mp it has cooled and therefore has decreased in volume. all this means that it no longer requires the full 3"'s.
 

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BlueScoob - the iON/Brullen turbo-backs are a 4" bell mouth design (like the Scoobysport) and merges into 3" about 6" after the turbo. It's 3" all the way back from there :)

SobeWRX - actually the only reason why it's 2.5" there is b/c TXS wanted those who didn't have the $$ to get the rear section to be able to use their old one. As well, all other "axle-backs" will bolt on there. It's not ideal if you're looking for peak performance, however it does the job.

You have to remember that since it goes down to 2.5" it "compresses" the gas flow again, causing turbulence and more back pressure. An exhaust will only flow as much as it's smallest diameter. It's kinda like a straw, if you have a constant flow (no kinks) it'll go pretty quick, pinch any part to reduce the diameter, you can only flow as much as that diameter will allow.
 

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unless of course the gas's temperature is changing. the reason it needs less space near the rear of the car is because the exhaust's temperature is decreasing the further back you go. the pipe is actually providing a cooling effect. it's the definition of the Ideal Gas Law. for an experiment, put a balloon in a microwave and watch the law in action. not to be smart, just thought i'd point that out.
 

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Discussion Starter · #11 ·
Interesting

I'm curious about this iON/Brullen setup. Hopefully, I can get more info on it's specs. So far the best setup I've investigated seems to be the M2, since its got 3" all the way through. However, I think the bell mouth on its downpipe could be more aggressive.

I know very little about the WRX, but I still can't help but think the extra flow of 3" over 2.25" will be noticed -- even if it is way back after the cat. It reminds me of the USDM vs. JDM headers in the Honda world. The 2.5" collector was far superior to the 2.25" and the difference was noticeable. I actually modded the flange on my exhaust's B-pipe to get rid of the 2.25" bottleneck.
 

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i will probably go with the 3" the whole way too. i can't wait to hear more about the Brullen either. i've been holding off on exhaust, waiting for more people to put them on and hear about it. i read several reviews on the M2 and its supposed to be one nice piece. i think it has some centering issues on the rear perch. looked slightly offline when looking at the muffler from the rear. good quality stuff though, from what i've read. anyone else with Brullen install stories?
 

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Discussion Starter · #13 ·
iON Turbo-back info

Thanks to Jack at iON Performance for such a quick response. Here's a snippet of the info on their Turbo back; it sounds like the one I'm going to get:

1)4" Bell-mouth down-pipe design, merges to 3" ~6"
from the back of the turbo.
2)Available in street spec or race spec (cat or no
cat)
3)3" 100 cell hi-flow cat is use for the street spec,
designed in Germany and is the most efficient hi-flow
cat design on the market.
4)Street spec can be converted into race spec in 5mins
or less.
5)All flanges are 3", there is no part of the system
smaller then 3"

All of our systems are manufactured from 16 gauge
T304SS, which is 53% thicker then the next closest
competitor, as well, we offer a limited lifetime
warranty on all manufacture's defects. All pieces are
mandrel bent and custom made to order (ie: w/ your
acoustic preferences as well as tip style)

Tip styles are: Single 3.5", 4", dual 3" and dual 3.5"
Acoustic preferences are: Quiet, Medium and Loud
- Quiet is just as quiet as stock @ idle and cruise,
only can be heard when under heavy throttle or WOT.
- Medium is more noticible @ idle and cruise, can be
heard under moderate throttle or WOT
- Loud is the closest thing you can get to the WRC
car, this thing is MEAN!

i-Club and ClubWRX members get a special price (I'm
assuming that's how you got our information).


The dual tip street spec turbo-back runs
$1249US+shipping (3" hi-flow cat)
[$1219US+shipping for single tip]

The dual tip race spec turbo-back runs $999US+shipping
(catless)
[$969US+shipping for the single tip]

Gains are on par with those of a Scoobysport system.
But as with most other parts on a turbo car, it's an
additive effect. Since it's minimum of 3" all the way
through, you're good for boosting up to 40psi with the
proper turbo and support.
 

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see...that'd be great, but a certain vender on here sells the entire TXS turboback for $800+shipping....that extra $400 can go a long way......
 

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Discussion Starter · #15 ·
That's a good point. Do you think you could email or im that member's name to me in case I do go with the TurboXS? I'm a newbie and don't know these things.
 

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gifty74 - you're right in the sense of the ideal gas law, however if you monitor your EGT's you'll notice that as boost and rpm's increase after-turbo exhaust temps increase as well. Hence only in steady-state "ie: idle or cruising speed" will the Ideal Gas Law be applicable.

One main theory exhaust designers use is based on pressure differentials created by temperature differences though a certain gradient. By keeping the maximal differential pressure between the source and the atmosphere you create maximal extraction, and maximal flow. When gas becomes compressed again @ the 2.5" section, temperature increases, this minimizing this differential and not maximizing flow.

djrez4 - you have a good point, however, you can only run 2.5" rear axle back sections with the TXS turbo-back, and you can't choose your tip styles nor your acoustic preference. But for $800US+shipping are you sure you want to run a "Magnaflow"? That's more or less a "universal" muffler that's used.
 

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The TXS is 1/2 the cost. I'm buying the TXS and a chip for the price I was going to pay for the MRT.

The TXS is also a bellmouth at the downpipe 4" down to 3". Both exhausts you asked about are quiet. Stealthiness rules.
 

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GTBGUY said:
gifty74 - you're right in the sense of the ideal gas law, however if you monitor your EGT's you'll notice that as boost and rpm's increase after-turbo exhaust temps increase as well. Hence only in steady-state "ie: idle or cruising speed" will the Ideal Gas Law be applicable.
i'm saying that as the exhaust travels back through the piping from the turbo it cools. as it cools it needs less space to flow through because it is compressing. it is based on the difference between the temps at the turbo and the temps at the tip of the muffler. the difference between these two temps is relatively the same no matter what throttle you're at. it's always going to cool the same even if the exhaust temp coming out of the turbo is higher. it's all relative to what the temps were at the turbo. the relationship between temps at the turbo and temps at the tip of the muffler is generallly the same, no matter what throttle position.
 
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