3.0RB exhaust - single rear muffler only??

[dan_ashcroft]

I am getting a set of Raptor headers in the next production run, and have been thinking of how I am going to set up the rest of my exhaust. Have been planning it out in my head for the last couple of weeks but am now spurred into action after finding a leak in a weld of a rear muffler.

From the experience of others on the forum (Daytona esp) and one of Tradewind's videos of the the 3RB without mufflers, I think the best option is probably to keep a good flowing mid muffler and let that do the majority of the work. If I do that...

Apart from there possibly being nothing to fill in the cutout in the bumper, is there any reason why I can't get rid of the drivers side muffler and just run an aftermarket passengers side? It's one less muffler to buy, and should give me a couple(?) of kgs weight saving. Everything is flexible in the plan, looking for some advice. Btw, I notice that the Gen 5 is single rear muffler.

Raptor headers
200 cell cats
y pipe into 2.5" oval mid muffler
2.5" piping into 2.5" passenger side rear muffler (a la Gen 5).

I'd be happy to pick up a late model WRX twin tip muffler, but looks like it is smaller than 2.5", maybe 2.25"? A 2.5" single muffler would be the size I need for a 3.0 NA right?

Thanks

[HardwareBoB]

Because it would look weird.

Gen5 GT is still dual.

[dan_ashcroft]

Because it would look weird.

Gen5 GT is still dual.

Hehe, yeah maybe. I'm not that fussed about it to be honest. I would probably get a twin tip muffler, I think that would it would look OK. I actually think quad tips is what truly looks weird. :/

[McDoof]

No reason you can't do it though. You should be able to get a filler for the gap too. The stock 2.0R only has a single muffler and has a filler for the other side.

[andy_mac]

Quite a few in there rocking the single tips. If you can get the cap for the other cutout she'd look spot on.

http://legacygt.com/forums/showthread.p ... 14550.html

[McDoof]

Speaking of single tips
http://forum.liberty.asn.au/viewtopic.php?f=16&t=23699&start=45#p416012

[dan_ashcroft]

No reason you can't do it though. You should be able to get a filler for the gap too. The stock 2.0R only has a single muffler and has a filler for the other side.

Thanks for the tip.

So double checking, I'm on the right track with 2.5" exhaust, yeah?

[BillyCorgi]

Depending upon your year model, there is a right hand side blanking cover available for the pre-facelift rear bumper cover.
Look at item #16 here
http://opposedforces.com/parts/legacy/e ... tration_1/

[McDoof]

No reason you can't do it though. You should be able to get a filler for the gap too. The stock 2.0R only has a single muffler and has a filler for the other side.

Thanks for the tip.

So double checking, I'm on the right track with 2.5" exhaust, yeah?

If you ask Daytona, he will probably say that he felt that he lost a bit of power when the 2.5" went in. You may be better off with just a 2.25". I can't really comment because I am still running the stock mid section and rear Y at this point which are a smaller diameter. 2" into twin 1 7/8" I think.
I will probably run a giant (500mm) twin 2.25 straight through muffler on my setup when the time comes to change it though. Should shut the beast up nicely. I like a note, not a noise

Also keep in mind at putting in high flow cats will create rasp in the note. This can be remedied with resonators. Again this is from Daytona's build.
Always worth checking with your tuner as to what he feels he can tune the most out of. I am assuming you are going with Matt?

[McDoof]

Part number for the bumper cover is 57731AG210

[dan_ashcroft]

Billy/Mcdoof - thanks for the part number. Partsouq has some listed in their supply chain, so will get one once I can think of a couple of other items to get at the same time.

I'm going to have to re-read Daytona's thread re the 2.5" tomorrow.

Yes, going with Matt, will ask him next week in person when I get my E85 tune done.
I might just take it to an exhaust shop to get it touched up while I stew on all the options available.

[dan_ashcroft]

So I've gone through Daytona's thread again, and it is 2.5" up until the final y where it splits out to the 2 mufflers. Also looking at the Xforce systems for the H6 and they are 2.5" until they split into 2 x 2.25", which is actually larger than 1 x 2.5". So far, I think 1 x 2.5" muffler is the direction to head in.

Another question, what will flow better, a custom y pipe after the 2 x 2.5" cats, or this magnaflow muffler (2 x 2.5" inlets into 1 x 2.5" outlet):

diso.jpg (20.83 KiB) Viewed 21786 times

My initial thoughts would be that the internal y might be better as it would join after it had slowed down slightly, but actually it joins fairly soon after entry. And although it is only a computer sketch, I am thinking the y pipe in the magnaflow looks a bit clunky. Get the traditional exhaust shop y-pipe instead?

[McDoof]

A custom Y will no doubt flow better. Perforations slow your gases. However that looks like it will keep it nice and quiet. Something you might want of you are fitting high flow cats.

[dan_ashcroft]

Only took a year to get to...

[dan_ashcroft]

Some pics and info for BBB (requested in another thread).

Raptor headers, ceramic coated > 2.5" pipe work (all the way through) > Magnaflow 200 cell cats > 2.5 Magnaflow center (center in, side out) > a single 2.5" Ultrex muffler (L/H side).

Got rid of the heat shield above the center muffler to give it enough room as it is slightly fuller than the standard center muffler.