TT 5.3 with post-turbo x-pipe
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Teching In
Joined: May 2022
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TT 5.3 with post-turbo x-pipe Hi all, not a performance related question here but an exhaust tone question. I currently have a 5.3 swapped BMW 850i with an Elgin 1839p (220/224 .525" 112lsa) and a single 7875 on 15 pounds and I hate the way it sounds. Exceptionally deep and toneless sound. Sounds like a rusty Silverado with a Pep Boys exhaust. The sound out of the tailpipe is fairly quiet (which is what I want), but the drone inside the cab is insane at low speeds.
Current setup is as follows:
Potential setup would be as follows:
Thanks!
Current setup is as follows:
- single 7875
- 4" to 3" downpipe
- Downpipe splits into dual 3" sections, each with a cat, resonator, and Thrush Hush Turbo muffler exiting in stock location behind rear bumper
Potential setup would be as follows:
- Dual 3582s
- Dual 2.25" downpipes to 2 cats and 2 resonators (1 cat/resonator per side)
- 2.25" x-pipe
- Mufflers
Thanks!
If its flowing through the turbo... a cat... a big muffler... AND its a rear exit exhaust.... I dunno what else will help you with drone.....
The twin turbo setups I have heard dont really sound that much different than single setups once once you run exhaust out the rear...
Something you may want to look into is a Helmholtz resonator, interestingly this is a topic that has been coming up frequently lately.
@rotary1307cc made one for his car that he says made a huge difference, he'd been a great source to tap about it.
@rotary1307cc made one for his car that he says made a huge difference, he'd been a great source to tap about it.
New Corvettes sounds BA because it’s a dual plane crank and a different firing order.
The firing order of the SBC mixed with true dual exhaust has always made it sound less than amazing IMHO. 180* manifolds and or big compression are about the only things that make it sound good to me personally.
X-pipe won’t do much for you and is less than ideal for a turbo setup. Might look into a resonation “J” chamber to eliminate the drone on your current setup. They are made to length depending on the tone you want to cancel out and work amazingly well. Draw back being you have to get someone who knows what they are doing to build one, if you don’t want to do the research.
The other option that I prefer will save you a lot of weight and money. Get a simple 3-4” cut out up front. Then run a crush bent single 2.25” exhaust system through a single factory style muffler at the rear. No cross overs, no big heavy hard to package 3” pipe. No resonators, cats, etc… None of that is needed to have a factory quiet car. Then you have the dump if you want to race or be loud.
The firing order of the SBC mixed with true dual exhaust has always made it sound less than amazing IMHO. 180* manifolds and or big compression are about the only things that make it sound good to me personally.
X-pipe won’t do much for you and is less than ideal for a turbo setup. Might look into a resonation “J” chamber to eliminate the drone on your current setup. They are made to length depending on the tone you want to cancel out and work amazingly well. Draw back being you have to get someone who knows what they are doing to build one, if you don’t want to do the research.
The other option that I prefer will save you a lot of weight and money. Get a simple 3-4” cut out up front. Then run a crush bent single 2.25” exhaust system through a single factory style muffler at the rear. No cross overs, no big heavy hard to package 3” pipe. No resonators, cats, etc… None of that is needed to have a factory quiet car. Then you have the dump if you want to race or be loud.
Hi all, not a performance related question here but an exhaust tone question. I currently have a 5.3 swapped BMW 850i with an Elgin 1839p (220/224 .525" 112lsa) and a single 7875 on 15 pounds and I hate the way it sounds. Exceptionally deep and toneless sound. Sounds like a rusty Silverado with a Pep Boys exhaust. The sound out of the tailpipe is fairly quiet (which is what I want), but the drone inside the cab is insane at low speeds.
Current setup is as follows:
Potential setup would be as follows:
Thanks!
Current setup is as follows:
- single 7875
- 4" to 3" downpipe
- Downpipe splits into dual 3" sections, each with a cat, resonator, and Thrush Hush Turbo muffler exiting in stock location behind rear bumper
Potential setup would be as follows:
- Dual 3582s
- Dual 2.25" downpipes to 2 cats and 2 resonators (1 cat/resonator per side)
- 2.25" x-pipe
- Mufflers
Thanks!
Andrew
Thread Starter
Teching In
Joined: May 2022
Posts: 7
Likes: 0
Something you may want to look into is a Helmholtz resonator, interestingly this is a topic that has been coming up frequently lately.
@rotary1307cc made one for his car that he says made a huge difference, he'd been a great source to tap about it.
@rotary1307cc made one for his car that he says made a huge difference, he'd been a great source to tap about it.
Those "turbo" mufflers aren't doing you any favors. To me they sound horrible even NA, and they are absolutely the worst for back pressure in a turbo system. I bet if you replace them with any number of different straight through mufflers, the tone will get better and I bet it will sound better inside too.
Andrew
Andrew
I'm speculating that the 4" to 3" downpipe with dual 3" pipes out of the back is just too large to effectively quiet down. Sticking my head under the car while it's running, downpipe and split after the downpipe and before the cats is where the majority of the noise is coming from; just too much room in there for sound to bounce around before it gets pushed through the cats.
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I ran an x-pipe in my setup and had lots of issues trying to find sound examples before I did it. Here's a vid that I made that I hoped would help anyone else looking for this style setup. It consists of twin bw S362's into dual 3" exhaust into an x-pipe and then exits at my bumper. Cam isn't too crazy. I think it sounds perfect for me though the video seems maybe a bit louder than it is in person. I can start it in my garage and talk to someone near it if I want. I think there is a dyno vid if you want to hear it go WOT as well.
https://youtube.com/shorts/HQtWUJsyhSQ
https://youtube.com/shorts/HQtWUJsyhSQ
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Verdad Gallardo I'm a big fan of using a cutout up front, and running some or all of the OEM mufflers. BMWs of that era had big and bulky mufflers that did an excellent job (almost too good) of quieting down the exhaust.
The quarter wave resonators (J-pipes) are effective but can be tricky to package and only work at the frequency they're designed for.
My current swap car is an '84 Jaguar with a turbo 6.0, with a 3" downpipe merged into the factory dual 1.75" exhaust. The cutout is boost activated and opens automatically once you get into it. I did some testing before/after hooking up the cutout, and it picked up almost 3psi of boost just by reducing exhaust backpressure. The car is nearly silent driving around town, but gets rowdy when you get on it. Best of both worlds.
https://www.ebay.com/itm/23438371316...UaAiTjEALw_wcB
The quarter wave resonators (J-pipes) are effective but can be tricky to package and only work at the frequency they're designed for.
My current swap car is an '84 Jaguar with a turbo 6.0, with a 3" downpipe merged into the factory dual 1.75" exhaust. The cutout is boost activated and opens automatically once you get into it. I did some testing before/after hooking up the cutout, and it picked up almost 3psi of boost just by reducing exhaust backpressure. The car is nearly silent driving around town, but gets rowdy when you get on it. Best of both worlds.
https://www.ebay.com/itm/23438371316...UaAiTjEALw_wcB