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NAturalDC2 said:
world sports exhaust by apexi and ill put money on it :up: can barely hear it only when you open up
werd, my buddy has it on his Accord, you can barely hear it! Only when its on WOT you can hear it, and even then its not that noticeable.

Or if you want a 2.5 piping exhaust, a dude on preludeonline.com did the perfect combo for quiet and high flowing:

http://www.preludeonline.com/showthread.php?t=169745&highlight=quiet+exhaust

Or if you aren't a member, here's what he posted:

Well, it's taken forever, but I've finally done it.

After much research and experimentation, I think I've found what I think is a perfect custom exhaust system for my lude. My goal: build as economically as possible the most quiet 2.5" dia straight-through system for the lude possible. The current setup I've stumbled upon has far exceeded my expectations!

I'm just thrilled right now to know that it is even possible to do this with the lude! In three words, this system is amazingly DEEP, SMOOTH, and QUIET.

As obnoxious as straight-through 2.5"systems can sound, my ideal was to get something that sounds like my former Apex'i WS; as hard as it is to believe, what I ended up with sounds like a V6--even better than a WS. I am extraordinarily picky, and don't think I say this inaccurately.

The review: On idle it is practically silent, with an almost subsonic bass hum. On acceleration, it emits a deep quality tone, not loud, not anywhere close to a rasp. Slightly louder than a WS, but exactly the pleasing throaty bass you want to hear. And the more you press down on the accelerator, the deeper and deeper this baby gets, just like a V6. It never gets that cheap boomy/struggling quality; instead it sounds robust. When you let off the accelator there's just a hint of more throaty bass. On WOT, all you hear is engine, and just a slight bassy growling from the back. On cruising no matter what speed it is nearly silent, no drone. Perfect. For an idea of the sound, it's very similar to (but quieter than) the clip that plays when you go to magnaflow.com.

The difference between a free-flowing straight-through system and a baffled/more restrictive one is remarkable. The whole RPM range is totally smoothed out, so smooth that sometimes you can't even tell when you've crossed over to VTEC. I still have to wire my VAFC and get a dyno, so these comments are subjective right now.

In brief, I went through 3 mufflers and tips to get here. First, I had a Magnaflow 5" x 8" x 18" muffler. Nice, that same magnaflow smoothness, but was too boomy/loud on acceleration during street driving for my taste. Drew attention. I noticed that it strikingly quiets down after about 1-2 months of break in, but still too loud for me even after this. As I've said, I think that many people would actually like this and be perfectly satisfied. Probably very close to a Thermal. But I decided to try the Hytech Twin Loop 2.5" muffler which had gotten rave reviews by Artifex, I think based on a 2.25" system pre-muffler. I think having 2.5" pre-muffler makes a difference, since I found the Hytech to be in fact surprisingly louder than the Magnaflow, more prone to vibration/not as smooth, and much more noticeably restrictive. I don't want knock this muffler, since it is a beautiful piece and worked amazingly for Artifex; but for my particular setup it was as described.

I decided to go back to Magnaflow but with a bigger can this time, from 5"x 8" x 18" to a giant 5" x 11" x 22". It's a behemoth for trucks. But believe it or not, it just fits in there! It can be slightly embarrassing, but paint that baby flat black and no one will ever know. Oriented correctly there is enough clearance for no rattles and adequate play. I also added a Magnaflow resonated tip. Not sure how much its contribution is, but it looks great. It is the results with this can and tip that I'm so clearly blown away by.


So......

If you'd like to take the time build this same system, here is a full parts list and the cheapest prices I found. Keep in mind that some may consider that I've made significant performance compromises in this system as I've placed a resonator in every component possible: the cat itself, 2 actual resonators, a giant muffler, and a resonated tip. Theoretically, yes, flow will be somewhat worse with all this perforated pipe. But again, it obviously provided me with the sound I want, it feels plenty unrestricted, paired with my header I feel large gains, and--for what it's worth--Magnaflow has numbers showing flow differences between their resonators and straight pipe are insignificant.


1. High-Flow Cat

Magnaflow/Carsound 94406 with built-in Resonated Core, 2.5" ID, 4" x 7" x 15.5"
$68.47 from www.fulllineexhaust.com


2. Resonators

2 Magnaflow 14416 Stainless Steel Resonators, 2.5" ID, 4" round, 14" long
$58.35 each from www.fulllineexhaust.com


3. Muffler

Magnaflow 14576 Stainless Steel, 2.5" ID, 5" x 11" x 22"
$108.12 from www.fulllineexhaust.com


4. Exhaust Tip

Magnaflow 35175 Stainless Steel Resonated Oblong Rolled Edge, Angle Cut Tip, 2.75" x 5.25" x 9.75"
$52.26 from www.fulllineexhaust.com


5. Tubing

2 T304 Stainless Steel 2.5” OD, 16GA, 90 degree long bends, 5.187 CLR
$19.08 each from Vertex Industries on Ebay, these are for the S bend

2 T304 Stainless Steel 2.5” OD, 16GA, 45 degree short bends, 3.75 CLR
$11.24 each from Vertex Industries on Ebay, these are for the axle-back section

4 ft T304 Stainless Steel 2.5" OD straight pipe
$7.18/ft from Vertex Industries on Ebay, some extra in case there's a goof


6. Hardware/Misc

02 Bung for after-cat position
$5 at local muffler store, needs to be welded onto cat

4 3-bolt flanges and nuts/bolts, cold rolled steel, for a total of 2 joints
$20 at local muffler store, stainless steel flanges are too expensive, at $35 each piece!

2 3-bolt flange gaskets
$2 each at Murray's

Stainless Steel Hangers
Do not buy these (ridiculously expensive)! Just have whoever is welding your system bend some out of stainless steel 3/8" wire, willl need 5 total

Rustoleum High Heat Flat Black Enamel
$4 from Home Depot


7. Labor to Weld Components
~$200 at local muffler shop, or whatever you can get; I'd recommend slip joints (welded) rather than butt welds



Total Cost

$345.55 from www.fulllineexhaust.com (cheapest prices by far, free shipping over $50!)

$82.18 + S/H (say $92.18) from Vertex Industries

$34 for hardware from local stores

$200 welding cost
_________________

$671.73


The system can be had for significantly cheaper by choosing aluminized steel instead of stainless.

I will post pics as soon as some finishing touches are made. But you can get an idea from my previous threads on this topic. Can also try to make an audio recording.

Comments are welcome, and I'd be glad to answer any questions. Hopefully you guys can benefit from all the money, time, and patience I've had to put into this!!! But now our community knows a quiet 2.5" can be done!

Happy luding!

dev
 

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Here are the pics, I'm not into rectangular tips, but you can always op for a different one:

Normal view of car, no trace of huge can:


Another view:


Back shot:


From street level, you can see the underside of the can:


Full view of can from underneath car:


View looking through rim to show how back of muffler comes right up to this rear control arm; it's not touching! There's about an 1 inch between and above the muffler, although you can't see it from this angle:


Here you can kind of tell that there is a distance between the muffler and that mount for the control arm:


An angle showing the full length of piping; you can make out the cat, two resonators back to back, S bend, axle back bends, muffler. Yes, I know the welds are crappy, and I wish I could go back and do it over again, but this is what I got. That's why I'd recommend doing slip joints instead of butt welds:


The resonated tip:


So that's it. There are still some finishing touches, like I need to cut off the tip and place it a but further back since I think it sticks out too far. And I'll repaint the can where some chips were made during installation.

But overall you get the idea.
 

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And of course, sound clips :)

Ok, clips are up. They are kind of crappy, but they give you an idea. I'll try to get some clips inside and outside with the car moving on a real street. I think the clips sound pretty good. You might think the sound of the exhaust is nothing special, but remember that this is a straight-through 2.5" exhaust with mandrel bends (which you'd expect to be horrendously loud)!

The first clip is from outside the car with engine starting, some revving, then stopping.

Second clip again outside the car, just some revving.

Third is from inside the car with some revving and accelerating in 1st in a parking garage.

right click and save as:

http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU2OTAwNnM0MTNkZmQzMXk1NDE=

http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU2OTAxNnM0MTNkZmQzMXk1NDE=

http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU2OTAyNnM0MTNkZmQzMXk1NDE=
 

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Hungry for more? Well here you go! :D

Some clips of the car moving. These are the best I could do for now! Interior clips are from taping the camera to the passenger seat, and exterior ones are from resting the cam on the back of some guy's parked van!!! Soon as I can go out with someone else, will try to generate some more dynamic clips. But for now, here you go:

1. Interior, starting the car, revving a bit, then accelerating on a local street.
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU3NjMyNnM0MTNkZmQzMXk1NDE=

2. Interior, starting, then a few cycles of accelerating then decelerating, then stopping with rev-matching.
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU3NjMzNnM0MTNkZmQzMXk1NDE=

3. Interior, cruising on the highway. Cruising at ~65, the accelerating. Notice sound on acceleration (still a bit boomy for me, but acceptable), then notice the sound when coming off throttle.
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU3NjM0NnM0MTNkZmQzMXk1NDE=

4. Interior, gunning it onto an onramp. Could only get up to third before traffic hit. Rev-match while downshifting for stop.
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU3NjM5NnM0MTNkZmQzMXk1NDE=

5. Exterior, car approaching. Unfortunately, could only get up to 3rd gear. Nice burble as I let off gas at end of clip.
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU3NjMwNnM0MTNkZmQzMXk1NDE=

6. Exterior, accelerating away from a stop, then approaching to a full stop.
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wODU3NjMxNnM0MTNkZmQzMXk1NDE=

Enjoy! and thanks to devtec of preludeonline.com for being the guinea pig and proving that a 2.5 exhaust CAN be quiet and high flowing at the same time, and the sweet video clips :dance:
 

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Go with a ES oval Exhaust, Flat Black With a Tip. People around me have it. Mated with 2 different sized resonators and a High Flow Cat it should sound pretty much stock unless your at WOT. A couple of people i knew had this setup.

One time a cop pulled over my friend and looked over his car looking for things Illegal (VA is the new Cali) and commented that at least the Exhaust is stock LOL.
 

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No problem guys :)

lol, and about VA becoming the next CA, that's no lie, I know a few guys who've gotten tickets down there for dumb reasons---too dark tint, loud exhaust, blue HIDs, you name it. I live in MD :rolleyes:

and not to mention anything 15mph over the speed limit is automatically reckless driving :confused:
 

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Good info Y2A :up: Ive always liked Magnaflow, i live few minutes from a shop that specializes in Magnaflow exhausts and all the cars/trucks that come out of there with a new exhaust sound nice!

I hope that "VA thing" doesnt spread to NC! My car is loud as shit; No Cat, 1-piece mandrel-bent 2.5" exhaust with Magnaflow-imitation muffler.
 

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I am just curious guys how many Whp we gains from cat stock to exhaust complet with muffler stock compared to an 2 1/4 straight , no cat or 2 1/2 praticly straight no cat , just magnaflow muffler, how many whp did we expect to win? 15 whp? at the top end? thanks!
 

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highrevnef said:
yea es oval is real good and a reasonable price. i have that on my hatch with a test pipe and 2 1/4 piping and u can barely hear until i pop vtec
The question is not if its nice sound, DID that make more power , did you feel it or not?
 
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