baconbits Posted March 22, 2018 Share Posted March 22, 2018 Small diameter bullet mufflers like you have won't do it. You need as much cross section as possible on the muffler body. 4" diameter muffler on 3" pipe is very thin, for example, and won't do much of anything. See if you can get 6" diameter or something like that. Source: exhaust engineer day job Link to comment Share on other sites More sharing options...
rebourne Posted March 22, 2018 Share Posted March 22, 2018 Single high flow cat, stock mid resonator swapped for a bullet style and stock cans. Single high flow cat, stock mid no resonator and stock cans. The bullet resonator made a big difference. pic thread build thread Link to comment Share on other sites More sharing options...
RecklessWOT Posted March 23, 2018 Share Posted March 23, 2018 I do not believe it will turn the decibels down a lot, but often makes it more "mellow" and eliminates harsh notes. Sometimes just because something is 'low and bassy' it seems very loud. Some angry bitch walking her dog jumped out of her yard onto the street today to wave her hand at the ground to tell me to slow down this morning on the drive to work. I was going about 29mph in a 25 zone. But oh no I drive a turbo subaru with an exhaust. I waved, and once I was 10 feet past her I put it back in 2nd and punched it, drifted the corner on the sandy pavement as a nice **** you. I'm sorry my exhaust has a low bassy sound to it, that doesn't mean I'm going fast. You wanna complain, I'll give you something to complain about... Link to comment Share on other sites More sharing options...
Guest Posted March 23, 2018 Share Posted March 23, 2018 Some angry bitch walking her dog jumped out of her yard onto the street today to wave her hand at the ground to tell me to slow down this morning on the drive to work. I was going about 29mph in a 25 zone. But oh no I drive a turbo subaru with an exhaust. I waved, and once I was 10 feet past her I put it back in 2nd and punched it, drifted the corner on the sandy pavement as a nice **** you. I'm sorry my exhaust has a low bassy sound to it, that doesn't mean I'm going fast. You wanna complain, I'll give you something to complain about... If you were going 29 in 25 mph you were going too fast. Maybe your state has prima facie speed laws, even then speeding in residential zones is a stupid and shitty thing to do. 29 vs 25 mph may make difference between life vs. death for a pedestrian. Try to think about it. I understand it seemed satisfying to show her, but an adult thing to do was to wave sorry and slow down. <---- I have very little regard for speed limits on highways when conditions permit to go fast, even reeaaaaalllly fast, but in residential areas I am a grandma. Link to comment Share on other sites More sharing options...
covertrussian Posted March 23, 2018 Share Posted March 23, 2018 I've had that happen to me once too on a slow-ass Sentra with an exhaust. Loudness != speed. As for speed, 29mph in 25mph is not bad, I got 30mph all the time and never had an issue, plenty of time to see the pedestrians and brake. With that said, in VA everyone goes 35mph in 25mph zone, but continues going 35mph in 35-45mph zones. 05 LGT 16G 14psi 290whp/30mpg (SOLD) 12 OBP Stock 130whp/27mpg@87 Oct 00 G20t GT28r 10psi 250whp/36mpg 22 Ascent STOCK Link to comment Share on other sites More sharing options...
Guest Posted March 24, 2018 Share Posted March 24, 2018 I've had that happen to me once too on a slow-ass Sentra with an exhaust. Loudness != speed. As for speed, 29mph in 25mph is not bad, I got 30mph all the time and never had an issue, plenty of time to see the pedestrians and brake. With that said, in VA everyone goes 35mph in 25mph zone, but continues going 35mph in 35-45mph zones. Don't take my word for it. https://www.roadandtrack.com/car-culture/a14500765/new-york-city-vision-zero/ http://humantransport.org/sidewalks/SpeedKills.htm Again this country is so fucked up to have 30-35 mph limits in pedestrian areas, yet 65-75 mph on highways. The former is changing (slowly), the latter not so much, maybe except TX. Take VA, your stupid nazi state, gives you reckless for 80+mph. 90mph should be the default speed limit on most highways. 100 mph is an easy cruising speed on a good highway. Though it requires attention from other drivers, something unthinkable here, I know. Link to comment Share on other sites More sharing options...
Wasted Potential Posted March 24, 2018 Share Posted March 24, 2018 I think speeding tickets should be a percentage over the limit, not a constant value Link to comment Share on other sites More sharing options...
covertrussian Posted March 24, 2018 Share Posted March 24, 2018 Anyway, back to exhausts. My current setup is quieter then Varex closed at idle, I bet it flows close to same with Varex being fully open too and flows MUCH better then it being closed. Once again that can barely has any volume to it, so sound can't properly dissipate. Makes me wonder if we could use a firearm suppressor design to make a straight through muffler be much quieter. I wonder if I still a rice muffler in my garage to weld up... 05 LGT 16G 14psi 290whp/30mpg (SOLD) 12 OBP Stock 130whp/27mpg@87 Oct 00 G20t GT28r 10psi 250whp/36mpg 22 Ascent STOCK Link to comment Share on other sites More sharing options...
Wasted Potential Posted March 24, 2018 Share Posted March 24, 2018 I'd assume a gun silencer wouldn't install the same % of decibel decrease in a firearm as muffler. I mean maybe 10% more effective? Get more technical again Please! I enjoy it when you do. What design factor does it utilize that a straight through doesn't? I haven't seen a split open silencer! Link to comment Share on other sites More sharing options...
RecklessWOT Posted March 24, 2018 Share Posted March 24, 2018 idk how I got this double post hours apart... disregard Link to comment Share on other sites More sharing options...
Wasted Potential Posted March 24, 2018 Share Posted March 24, 2018 Trust me, my exhaust is loud and bassy. I have heard loud and quiet, and my area has no decibel limit unless physically posted. So... I don't care. Link to comment Share on other sites More sharing options...
covertrussian Posted March 24, 2018 Share Posted March 24, 2018 I'd assume a gun silencer wouldn't install the same % of decibel decrease in a firearm as muffler. I mean maybe 10% more effective? Get more technical again Please! I enjoy it when you do. What design factor does it utilize that a straight through doesn't? I haven't seen a split open silencer! Typical resonators are like suppressors, but not as well engineered (read: they are much simpler, with no baffles just some steel wool like contents inside). You could use a typical resonator as a suppressor, but it wont be too effective since diameters are way different, but if it is effective at reducing even some dB of a .22lr (typically 140db and is "stupid quiet compared to real calibers"), you just committed a felony. I can't seem to find a straight pipe DB of a turbo Subaru (because turbo works like a muffler and would be quieter then NA, aka the muffler bearing!). But I did find this article, which compares 2002 WRX stock vs aftermarket exhaust's dB's. Stock is 87dB at idle, and most aftermarket seem to be between 94-104dB, so that's about 7-17dB reduction. At best the stock restrictive setup reduces noise by 17dB, at worst by 7dB. I would say suppressors actually do more noise reduction then car mufflers do, but they also have a big pressure wave instead of constant smaller waves. In comparison, a remington 700 in .308 is 167dB, with a Dakota suppressor it's 140db, that's a massive 27db reduction. Source, warning PDF Next time I'm outside I'll measure my dB levels and I'll try to grab a video, especially since I'm on UEL header now again, but if I had to venture an educated guess, mine is around 90dB. Reason I say that is, my turbo G20 (with very similar 3" exhaust and STI muffler) was clocked at 88dB@50ft while autocrossing. When my friend drove it, it sounded like a bone stock car. 05 LGT 16G 14psi 290whp/30mpg (SOLD) 12 OBP Stock 130whp/27mpg@87 Oct 00 G20t GT28r 10psi 250whp/36mpg 22 Ascent STOCK Link to comment Share on other sites More sharing options...
RecklessWOT Posted March 24, 2018 Share Posted March 24, 2018 If you were going 29 in 25 mph you were going too fast. Maybe your state has prima facie speed laws, even then speeding in residential zones is a stupid and shitty thing to do. 29 vs 25 mph may make difference between life vs. death for a pedestrian. Try to think about it. I understand it seemed satisfying to show her, but an adult thing to do was to wave sorry and slow down. <---- I have very little regard for speed limits on highways when conditions permit to go fast, even reeaaaaalllly fast, but in residential areas I am a grandma. Cry about it. 4mph isn't gonna kill anyone. She's lucky I was only going 29, I was doing that as a courtesy to the people who live on the street. Life and death? Get real. There's this pedal in the middle called the brakes, if I see someone in the road who's in danger common sense will slow me down. Not like I was going 70 and sliding sideways risking lives. Yeah I thought about it, and her bitchy attitude made sure I punched it anyway. People need to mind their business... Idk about where you live, but it has nothing to do with laws. If I was worried about the law I'd be a cop. Around here AND where I grew up (hundreds of miles apart) people use common sense and go 10-15 over the limit when being cautious. I bet if I were driving a brand new car with super quiet exhaust I could have been going 50 and she wouldn't have noticed or cared. Yet the fact that my car goes "brrrrrRRRT... PFFfttt" at 29mp is enough to make her jump up and down. Have you ever gone 29mph? That feels slow in an elementary school parking lot... It's not a dangerous street and at that time of day nobody is out, she's lucky I wasn't going 50. You wanna complain about 4mph then you and I are not the same kind of people... Link to comment Share on other sites More sharing options...
Wasted Potential Posted March 24, 2018 Share Posted March 24, 2018 Next time I'm outside I'll measure my dB levels and I'll try to grab a video, especially since I'm on UEL header now again, but if I had to venture an educated guess, mine is around 90dB. Reason I say that is, my turbo G20 (with very similar 3" exhaust and STI muffler) was clocked at 88dB@50ft while autocrossing. When my friend drove it, it sounded like a bone stock car. My fiancee is an audiologist and unfortunately wouldn't let me utilize her bosses sound level meter, it's like an absurd $3k super precise tool. In another life I'd love to be a sound engineer. I am very curious where my car would be numerically, and what the open wastegate on my old v8 turbo would have been... Exhausts are so simple yet so difficult at the same time! Link to comment Share on other sites More sharing options...
Guest Posted March 24, 2018 Share Posted March 24, 2018 Cry about it. 4mph isn't gonna kill anyone. She's lucky I was only going 29, I was doing that as a courtesy to the people who live on the street. Life and death? Get real. There's this pedal in the middle called the brakes, if I see someone in the road who's in danger common sense will slow me down. Not like I was going 70 and sliding sideways risking lives. Yeah I thought about it, and her bitchy attitude made sure I punched it anyway. People need to mind their business... Idk about where you live, but it has nothing to do with laws. If I was worried about the law I'd be a cop. Around here AND where I grew up (hundreds of miles apart) people use common sense and go 10-15 over the limit when being cautious. I bet if I were driving a brand new car with super quiet exhaust I could have been going 50 and she wouldn't have noticed or cared. Yet the fact that my car goes "brrrrrRRRT... PFFfttt" at 29mp is enough to make her jump up and down. Have you ever gone 29mph? That feels slow in an elementary school parking lot... It's not a dangerous street and at that time of day nobody is out, she's lucky I wasn't going 50. You wanna complain about 4mph then you and I are not the same kind of people... I suppose we are not. You know better and are above scientific evidence and laws of physics. Again, I do not know the specific street and conditions, but usually 25 mph is very likely there for a reason. Link to comment Share on other sites More sharing options...
Merc6 Posted March 27, 2018 Share Posted March 27, 2018 Small diameter bullet mufflers like you have won't do it. You need as much cross section as possible on the muffler body. 4" diameter muffler on 3" pipe is very thin, for example, and won't do much of anything. See if you can get 6" diameter or something like that. Source: exhaust engineer day job I might enlist your help when I get it running again, if that ever happens. I plan on replacing my bullet resonators for something else. The bullet resonator made a big difference. Yeah then I ditched stock cans for another members custom 1 off setup to go loud again.... LOL gonna change it again when car runs. 2005 Satin White Pearl Subaru Legacy 2.5 GT Unlimited 5EAT (Project Car) 2019 Agate Black Ford Explorer XLT 4WD (DD) Link to comment Share on other sites More sharing options...
robburns201 Posted March 27, 2018 Share Posted March 27, 2018 HKS Silent....IDK if this helps but it's got bass but about half the sound of Invidia quad pipes...IDK if this helps but at least I get to show it off... Sent from my 0PJA2 using Tapatalk Link to comment Share on other sites More sharing options...
RecklessWOT Posted March 28, 2018 Share Posted March 28, 2018 Anyway, back to exhausts. My current setup is quieter then Varex closed at idle, I bet it flows close to same with Varex being fully open too and flows MUCH better then it being closed. Once again that can barely has any volume to it, so sound can't properly dissipate. Makes me wonder if we could use a firearm suppressor design to make a straight through muffler be much quieter. I wonder if I still a rice muffler in my garage to weld up... I feel like that would cause too much backflow and therefore restriction. The whole way a silencer/suppressor on a gun works is reducing gas pressure and slowing the bullet to sub-sonic levels so there is no "crack" out of the barrel. If you put that much turbulence into a car exhaust to slow it enough to quiet it down that much you're very likely left with something like stock exhaust if not even more restrictive. Link to comment Share on other sites More sharing options...
covertrussian Posted March 28, 2018 Share Posted March 28, 2018 I feel like that would cause too much backflow and therefore restriction. The whole way a silencer/suppressor on a gun works is reducing gas pressure and slowing the bullet to sub-sonic levels so there is no "crack" out of the barrel. If you put that much turbulence into a car exhaust to slow it enough to quiet it down that much you're very likely left with something like stock exhaust if not even more restrictive. It would create as much backpressure as any resonator does. Due to the big open space allowing the gasses to cool down and slow down. http://cdn.speednik.com/wp-content/blogs.dir/1/files/2015/03/06.jpg While quality resonators do in theory create some backpressure, it's so tiny it's usually not measurable in PSI. Louvered resonators are horrible, I sadly don't have a stock resonator to test how bad it is (I don't think it's all that bad) Also, firearm suppressors don't slow bullets down, instead you as the operator use subsonic rounds, otherwise your suppressing a bullet that will still have a loud sonic boom from being supersonic (read: it helps reduce noise on supersonic ammo, but not nearly as much as using suppressor + subsonic ammo). Modern suppressors allow the use of full-power ammunition, do not reduce the muzzle velocity, do not contact the bullet during flight, and often aid accuracy. On high-power rifles, a suppressor acts like a muzzle brake and reduces recoil, and of course, the “ka-BOOM” report of the shot is reduced 25-30 dB, yielding a sound not unlike high-pressure gas escaping from an air hose being disconnected. Source 05 LGT 16G 14psi 290whp/30mpg (SOLD) 12 OBP Stock 130whp/27mpg@87 Oct 00 G20t GT28r 10psi 250whp/36mpg 22 Ascent STOCK Link to comment Share on other sites More sharing options...
Merc6 Posted April 2, 2018 Share Posted April 2, 2018 What about these? https://www.flowmastermufflers.com/dbx-series/ 2005 Satin White Pearl Subaru Legacy 2.5 GT Unlimited 5EAT (Project Car) 2019 Agate Black Ford Explorer XLT 4WD (DD) Link to comment Share on other sites More sharing options...
covertrussian Posted April 2, 2018 Share Posted April 2, 2018 I've seen them, but never heard them in person or even found a good apples to apples comparison. The best I can find is this, but that's not a fair comparison because all those bends quiet down the exhaust quite a bit on their own. [ame=http://www.youtube.com/watch?v=LrBIVRbmKiw]Flowmaster Pro Series Laminar Flow Exhaust Mufflers Sound Testing HushPower - YouTube[/ame] 05 LGT 16G 14psi 290whp/30mpg (SOLD) 12 OBP Stock 130whp/27mpg@87 Oct 00 G20t GT28r 10psi 250whp/36mpg 22 Ascent STOCK Link to comment Share on other sites More sharing options...
stocklgt Posted April 2, 2018 Share Posted April 2, 2018 Vibrant is the answer for everything serious note though, either stock cans with 3" or a quiet setup like stromungs with an elh. Link to comment Share on other sites More sharing options...
xtea Posted April 2, 2018 Author Share Posted April 2, 2018 Vibrant is the answer for everything serious note though, either stock cans with 3" or a quiet setup like stromungs with an elh. If I dont bring back to stock and sell I am going to put in a high flow cat plus stock cans and live with the reduced performance. Probably gonna get a pump tune as well instead just e85. I got the race car out of my system at this point. Link to comment Share on other sites More sharing options...
Wasted Potential Posted April 2, 2018 Share Posted April 2, 2018 If you somehow have the ability to get it dynoed right before and after I would be curious of that... Can start betting... -16hp and -14 ft/lbs. Link to comment Share on other sites More sharing options...
covertrussian Posted April 2, 2018 Share Posted April 2, 2018 Find a consistent piece of road, do a couple before logs, swap exhausts do a couple after, graph in virtual dyno = profit. 05 LGT 16G 14psi 290whp/30mpg (SOLD) 12 OBP Stock 130whp/27mpg@87 Oct 00 G20t GT28r 10psi 250whp/36mpg 22 Ascent STOCK Link to comment Share on other sites More sharing options...
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