sleeper exhaust help

[eatwagondust]

I have searched fervently but I have been unable to find a good answer. Any insight would be great.

 

I currently have a catless invidia downpipe to the stock catback. I want to keep my stock mufflers for their quietness and their sleeperness. Would it be beneficial/possible to upgrade the midpipe and y pipe and connect to stock mufflers.

 

Do aftermarket y pipes connect to stock exhaust? Would I need any adapters? Would I see any noticeable gains from it? Is it worth doing and if so what would be best product to suit my needs.

 

Thanks

[boxkita]

I have a catted invidia to stock exhaust making 335wtq. It dynoed at ~369wtq. Swapping out more exhaust is going to make it louder, not really fitting in with your sleeper desire.

 

enlarging the size of the pipes will help your exhaust the most. As for the various brands, you should search out the various sound clips and comments. Many of the mid-pieces add drone with little benefit.

[BarManBean]

From my reading in the past, your best bet is probably to swap to a catted downpipe (slight reduction in noise) and pick up a mid / y pipe and have a muffler welded in instead of a resonator if the mid/y pipe has one. Some aftermarket y pipes connect to stock exhaust--Perrin, Nameless, maybe others...? Probably easiest to just go to an exhaust shop and have them make you a 3" custom mid / y with a muffer in it.

[WaspGT]

Sleeperness?

[stm25rs]

I have searched fervently but I have been unable to find a good answer. Any insight would be great.

 

I currently have a catless invidia downpipe to the stock catback. I want to keep my stock mufflers for their quietness and their sleeperness. Would it be beneficial/possible to upgrade the midpipe and y pipe and connect to stock mufflers.

 

Do aftermarket y pipes connect to stock exhaust? Would I need any adapters? Would I see any noticeable gains from it? Is it worth doing and if so what would be best product to suit my needs.

 

Thanks

 

What are your goals? Are you looking for more power while keeping the exact same stock (lack of) sound? Or are you looking for a little more noise, and maybe some extra power, without going outrageously loud?

[ragman]

Here are all the MID/Y Pipes and comments on each:

 

-AVO. It's the most expensive, but real nice quality. Mates up with the stock mufflers or AVO mufflers. These are resonated. $699

 

-Nameless Performance. Also nice quality. Uses V band clamps.These are resonated. Mates up with the stock mufflers, their muffler deletes, or their small mufflers. Used to be $599, price just went up to $639.

 

-TURBOXS. Still nice quality. Mates up with stock mufflers or their recently released mufflers. Not resonated. Posted price is $549, but I know for sure they are giving great discounts with free shipping right now.

 

-eBay $280 SHIPPED! full exhaust with mufflers. Lowest quality, but still ok. Mates up with stock mufflers. But as mentioned comes with mufflers too. Used to be resonated, but the newer versions are not being shipped with resonators. Fitment is off out of the box, mufflers will hang low and crooked, but this can be fixed with heat and some muscle.

 

Personally, I want sleeper with the most power too. I am leaning towards the TURBOXS, and having a local shop add a resonator.

[eatwagondust]

What are your goals? Are you looking for more power while keeping the exact same stock (lack of) sound? Or are you looking for a little more noise, and maybe some extra power, without going outrageously loud?

 

My goal is responsive sleeper. I want 300awhp and could handle a little beefier sound but don't want noise. So yes essentially what you said.

[eatwagondust]

oh by the way have a front mount and getting an n/a outback hood for a bada## sleeper. I will be getting a 16g/18g also. i want to blend in and have the balls to back it up. Also be unique and appreciated by the real automotive connoisseur not the mudflap snots out here.

[spec.B452]

The Ebay special is not too bad with the resonator installed. If you do the full exhaust with a vf52 or other turbo upgrade and a tune the difference will be like night and day, easy 300whp before you have to upgrade your fueling system. I am very impressed with how these cars respond to mods.

[dahoseman]

The Ebay special is not too bad with the resonator installed. If you do the full exhaust with a vf52 or other turbo upgrade and a tune the difference will be like night and day, easy 300whp before you have to upgrade your fueling system. I am very impressed with how these cars respond to mods.

 

Definitely need the resonator if he goes the Ebay route. I bought the old OBX kit. It was so loud that I switched mufflers, added a resonator, and had high flow cats welded in. When I first had it installed, I couldn't carry on a normal conversation while loading gear into the hatch of my wagon if the engine was running. I couldn't take that. Then again, I like my cars to be nearly silent.

[eatwagondust]

Does anyone know of a thread of someone doing a fmic with scoop delete that I can look at or pick their brains?

[StoplightAssassin]

It's been done. You just have to get a 2.5i hood.

[Brett]

oh by the way have a front mount and getting an n/a outback hood for a bada## sleeper. I will be getting a 16g/18g also. i want to blend in and have the balls to back it up. Also be unique and appreciated by the real automotive connoisseur not the mudflap snots out here.

 

front mounts don't really work with the sleeper look.

[GEE-OTTO]

The best "sleeper" exhaust I have ever heard is on itsme LGT wagon i believe. Its a CBE with a Borla XR1 muffler welded in place as a resonator. All you hear is sweet spool and BPV noise

[ragman]

The best "sleeper" exhaust I have ever heard is on itsme LGT wagon i believe. Its a CBE with a Borla XR1 muffler welded in place as a resonator. All you hear is sweet spool and BPV noise

 

Which CBE?

[SSpeed]

I have a Cobb catted downpipe running to an AVO mid/Y-pipe back to the stock mufflers.

 

It's stock quiet, almost too quiet. When you first start it up you get an aggressive cackle until the resonator warms up, then you don't hear a thing. No one knows my car has anything done to it.

[eatwagondust]

I have a Cobb catted downpipe running to an AVO mid/Y-pipe back to the stock mufflers.

 

It's stock quiet, almost too quiet. When you first start it up you get an aggressive cackle until the resonator warms up, then you don't hear a thing. No one knows my car has anything done to it.

 

Yeah that's exactly what I wanted to know about with mid and y pipes. Any noticeable up in power with this mid and y set up?

[eatwagondust]

It's been done. You just have to get a 2.5i hood.

 

I realize that it has been done. Just wanted to do more research

[SSpeed]

I think the resonator is key if you don't want drone, and it has to be sized appropriately for the exhaust tone. AVO did it perfect, but man it's expensive.

 

My dyno chart is somewhere, IIRC I'm running about 50hp over stage2 and I've done some other small meaningful things, but don't quote me on that. I never tested with just a downpipe and the stock mid/Y so I can't give you any feedback there.

[iNVAR]

If replacing an entire catback on a 4th gen yields no measurable increase in performance, then replacing only the midpipes and Y isn't going to make a difference at all.

[serx7]

My goal is responsive sleeper. I want 300awhp and could handle a little beefier sound but don't want noise. So yes essentially what you said.

 

Just to add, my 05 OBXT has Cobb catted DP, Nameless resonated mid/Y, stock mufflers. It put down 303 whp / 339 wtq on a Mustang AWD 500 dyno w/ the other stuff I have installed.

 

Basically sounds stock with just a -hint- more burble. It previously had the Nameless 5" turn-down mufflers and IMO sounded muscle-car mean, but the cabin resonance w/ the wagon was too much even for me for my DD application.

 

My tuner mentioned that the mufflers would probably only make a ~3 whp improvement, so I'm perfectly happy w/ the way it's set up now.

[SSpeed]

If replacing an entire catback on a 4th gen yields no measurable increase in performance, then replacing only the midpipes and Y isn't going to make a difference at all.

 

It's true that mufflers made hardly a difference on a car with a 20g, I've never seen the data that shows no gain with mid/Y though? Peak power might be the same, but spoolup and range within the powerband may not be. My uneducated thought on an upgraded mid/Y was that it gives more volume behind the turbo on spool up and that potentially reduces back pressure on the turbine. Maybe an upgraded downpipe is all that's needed to achieve that?

[eatwagondust]

It's been done. You just have to get a 2.5i hood.

 

It's true that mufflers made hardly a difference on a car with a 20g, I've never seen the data that shows no gain with mid/Y though? Peak power might be the same, but spoolup and range within the powerband may not be. My uneducated thought on an upgraded mid/Y was that it gives more volume behind the turbo on spool up and that potentially reduces back pressure on the turbine. Maybe an upgraded downpipe is all that's needed to achieve that?

 

makes sense to me.. thats why i'm curious of anyones experience/knowledge with this

[iNVAR]

It's true that mufflers made hardly a difference on a car with a 20g, I've never seen the data that shows no gain with mid/Y though? Peak power might be the same, but spoolup and range within the powerband may not be. My uneducated thought on an upgraded mid/Y was that it gives more volume behind the turbo on spool up and that potentially reduces back pressure on the turbine. Maybe an upgraded downpipe is all that's needed to achieve that?

The most significant bottleneck is the area immediately after the turbo, which is the downpipe. A bellmouth and 3" exhaust allows the exhaust gas to expand and by the time it gets to the midpipe it has lost significant temperature and volume.

 

The 5th gens are, strangely enough, a different beast when it comes to this aspect. There's a good amount of testimony from various tuners about the huge benefits of a catback and tune on the 5th gens.

 

But the 4th gens? You should be asking yourself whether or not there's any evidence that it DOES make a difference, which is unlikely for you to find.

 

serx7 said his tuner said maybe a 3whp difference for mufflers. When I fart hard enough I make 3whp. The point is that such a small increase, if any, is soooooo small that it's next to impossible to measure unless under VERY, VERY controlled conditions. This goes not just for mufflers but for catback. There are guys that make huge power with only a DP and a fully stock catback.

[SSpeed]

Makes sense, I've wondered just how much volume after the turbo is needed to reduce backpressure, objective data like that would be impossible to find.

 

If I wasn't so lazy I could find the muffler thread, I think like you said it was an extra 3hp/20tq that upgraded mufflers made. The 20 ft lbs is something to cause question, but I'll keep the quietness for 20 ft lbs.

 

On the 5th gens, I saw a fair amount of threads back when I was more active on the forum that showed about the same gain as 4th gens. My take on it was that it was perception. 5th gen owners seem to overall be a different beast than 4th gen owners. Maybe more data has come out since then.