My new setup: Exoticspeed R1-T GT + Circuit Werks Resonated Y-Pipe
#16
It's actually been close to 1,000 miles, but either way I see no reason to touch it yet. Honestly I'm sort of hoping to either 1. buy a different car or 2. do a huge amount of upgrades once I finish school in Dec 2019 anyways, so no reason to throw money away yet. Only thing is, I can't decide whether to sell the OEM exhaust or keep it around for now.
#18
#19
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Location: Washington State
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Coupe 6MT Premium RAS
It's actually caused by FRICTION on another surface, an acoustical vibration.
It's exactly the same thing when you use a crystal wine glass and run your finger across the top to make that ear piercing ringing sound. Your finger is creating friction causing the mating surface to vibrate at a certain frequency. The same can be achieved by blowing air across a beer bottle, the AIR has friction and causes the bottle to vibrate at a specific frequency which can be audibly heard.
The air travelling through your exhaust has a lot of friction on the metal pipes of the system and the muffler, this is why rapid changes in pipe size is bad, it creates points like the edge of your beer bottle that can create these acoustics. Also just like your beer bottle it takes a VERY SPECIFIC amount of air across the surfaces of the system to cause drone. Increasing the overall flow of the system increases the CHANCE of drone but because of the amount of bends in the pipe and the internal baffling of the muffler drone is all but inevitable eventually because of the wide range of exhaust flow from idle to redline. Resonators are added to break up the airflow by allowing it to basically flow back on itself at the outside edges of the flow while the center of the airflow continues on at the same speed (thus they don't restrict the exhaust).
The best analogy I can give for this is to blow across the beer bottle to make it whistle, then lift your head so the airflow doesn't QUITE blow across the bottle and the noise stops. That's basically what the resonator is doing because it's just a pipe with a bunch of tiny holes in it inside a larger enclosure.
It's exactly the same thing when you use a crystal wine glass and run your finger across the top to make that ear piercing ringing sound. Your finger is creating friction causing the mating surface to vibrate at a certain frequency. The same can be achieved by blowing air across a beer bottle, the AIR has friction and causes the bottle to vibrate at a specific frequency which can be audibly heard.
The air travelling through your exhaust has a lot of friction on the metal pipes of the system and the muffler, this is why rapid changes in pipe size is bad, it creates points like the edge of your beer bottle that can create these acoustics. Also just like your beer bottle it takes a VERY SPECIFIC amount of air across the surfaces of the system to cause drone. Increasing the overall flow of the system increases the CHANCE of drone but because of the amount of bends in the pipe and the internal baffling of the muffler drone is all but inevitable eventually because of the wide range of exhaust flow from idle to redline. Resonators are added to break up the airflow by allowing it to basically flow back on itself at the outside edges of the flow while the center of the airflow continues on at the same speed (thus they don't restrict the exhaust).
The best analogy I can give for this is to blow across the beer bottle to make it whistle, then lift your head so the airflow doesn't QUITE blow across the bottle and the noise stops. That's basically what the resonator is doing because it's just a pipe with a bunch of tiny holes in it inside a larger enclosure.
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philbegas (07-17-2018)
#21
Ive experimented with so many test pipe/hfc/y pipe configurations around this exhaust and I'll tell you right now that I noticed the drone went away when I swapped out my stock cats to test pipes or HFCs.
i think what it really is is that the drone shifted into the lower parts of the rpm where's it's never noticable unlike the usual 2kish range where I will.
anyways I'll save you from gambling with choosing the right parts and I'd recommend HFCs over test pipes. When I had straight through test pipes, they were embarrassingly raspy and smelled so bad that Id lose IQ points at every stoplight I sit at.
I currently have Z1 100 cell HFCs and they are definately way less raspy but it's still there. Don't smell as bad either.
Through my experimentation, I find that the less cat material, the more raspy. Therefore I think the best choice if I had to do it all over again would be a 200/300 cell cat like fast intentions.
i think what it really is is that the drone shifted into the lower parts of the rpm where's it's never noticable unlike the usual 2kish range where I will.
anyways I'll save you from gambling with choosing the right parts and I'd recommend HFCs over test pipes. When I had straight through test pipes, they were embarrassingly raspy and smelled so bad that Id lose IQ points at every stoplight I sit at.
I currently have Z1 100 cell HFCs and they are definately way less raspy but it's still there. Don't smell as bad either.
Through my experimentation, I find that the less cat material, the more raspy. Therefore I think the best choice if I had to do it all over again would be a 200/300 cell cat like fast intentions.
#22
#23
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Exhaust manufactures spend days if not weeks testing their systems to avoid drone and increase WHP! They're always the same size diameter from header to tips where exit! No one can modify a OE exhaust and think you'll eliminate drone. You're vid doesn't sound bad and don't waste any more $$ trying to get rid of the drone you're hearing. If you plan on keeping your G I suggest you buy a used quality aftermarket exhaust from our Marketplace under private classified.
Good Luck & enjoy the ride...Gary
Good Luck & enjoy the ride...Gary
#24
I haven't experimented with resonated/nonresonated but from the YouTube videos I've watched, resonators seem to make this exhaust lose its "exotic" note, especially in the lower rpms.
i personally felt that stock cats/stock de Y pipe/r1-t sounded the most exotic,especially in the lower rpms around 2.5-3k. But it had the most drone and could've been louder.
Funny thing is that my Z1 100 cell non resonated HFCs sounded raspy when paired up with my Megan HR y pipe 2.5-3in, but the weird thing is that when I switched it back to my stock de Y pipe, the rasp went away. Exhaust note became "exotic" again. This is my current set up and it's currently my best configuration out of 7 I've tried with stock cats/y pipe being a close second.
Anyways in regard to your decision, idk which i would chose. Maybe since you already have resonated y pipes try a non resonated HFC.
From videos, too many resonators seem to quiet the car down too much but that's just me.
i personally felt that stock cats/stock de Y pipe/r1-t sounded the most exotic,especially in the lower rpms around 2.5-3k. But it had the most drone and could've been louder.
Funny thing is that my Z1 100 cell non resonated HFCs sounded raspy when paired up with my Megan HR y pipe 2.5-3in, but the weird thing is that when I switched it back to my stock de Y pipe, the rasp went away. Exhaust note became "exotic" again. This is my current set up and it's currently my best configuration out of 7 I've tried with stock cats/y pipe being a close second.
Anyways in regard to your decision, idk which i would chose. Maybe since you already have resonated y pipes try a non resonated HFC.
From videos, too many resonators seem to quiet the car down too much but that's just me.
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philbegas (08-29-2018)
#25
So I definitely get a little rasp (lift-off crackles and pops) but I actually like the amount that I get, and it still sounds pretty exotic. It's also loud as fffffff haha because I got the lightweight muffler version. My circuit werks y pipe is the same (2.5 to 3 inch). A non-resonated HFC might be the way to go, and the ISR one is pretty inexpensive. The only issue is I'm worried that it will become too loud for me to use lmao.
#28
#30
I've found the Vibrant Ultra Quiet resonator is very effective and cutting down drone drastically. Still have a tiny bit with my set up at 2500 rpm(Art Pipes, Circuit Werks resonated Y-pipe, Tanabe exhaust with the original resonator and muffler removed and replaced with the Vibrant resonator and Dynomax Super Turbo muffler respectively) but the volume now is maybe 1/10th what it was originally. The low speed tip in light throttle boominess is gone too. Sounds much cleaner when I get on it. Should have just had the local performance exhaust shop here build me an exhaust instead of buying the Tanabe and then having to cut it up and replace the resonator and muffler. Would have been cheaper.