Quieter downpipes?

Slim415 · 11-24-2022, 02:22 PM

Looking for DP's that are quieter then my VRSF catless ones. I would hope to keep the same performance gains but with less noise. After a couple years driving with mine, the sound is getting a bit much.

I know that adding Vibrant resonators would help, but I also heard that in doing so it would make your car smoke which I definitely do not want.

jwalker87 · 11-24-2022, 08:22 PM

Catless DPs are just tubes - only way you're getting 'quieter' ones are to get ones with cats. I'd either get some high-performance catted DPs or look elsewhere in your exhaust system for ways to tone down the noise a bit.

Why would adding resonators make your car smoke? What other modifications to you have to the exhaust (PE mod, etc.)?

Slim415 · 11-25-2022, 08:38 PM

Quote:

Originally Posted by jwalker87

Catless DPs are just tubes - only way you're getting 'quieter' ones are to get ones with cats. I'd either get some high-performance catted DPs or look elsewhere in your exhaust system for ways to tone down the noise a bit.

Why would adding resonators make your car smoke? What other modifications to you have to the exhaust (PE mod, etc.)?

It's a 335is with stock exhaust. I don't know for sure if it would smoke but that's what I read online.

Slim415 · 11-25-2022, 09:45 PM

Question about the catted DP's. How much of a performance loss is there compared to catless? And it's quieter as well?

whyzee125 · 11-25-2022, 11:02 PM

I'm guessing the smoke you're referring to would be the result of deleting the secondaries to replace with the resonators, and not the resonators themselves. A properly running car shouldn't smoke but sometimes aging turbos produce a little smoke that is masked by the cats.

I have the PE mod with VRSF catless and with the windows up it could easily pass as stock, just has a bit more buzz/rasp up high at WOT. I would make sure you don't have the golf tee mod or the tune equivalent if applicable and look into catted downpipes. You could expect a few less ponies but I'd be surprised if it's enough to be felt.

I've also heard of one member on here who heat wrapped his DPs and claimed it made it just as quiet as the stock ones. His words, not mine, but something that could be worth a try.

11-24-2022, 02:22 PM	#1
Slim415 Second Lieutenant 92 Rep 281 Posts Drives: 2011 335is 6MT Join Date: Jul 2019 Location: SF, CA iTrader: (0)	Quieter downpipes? Looking for DP's that are quieter then my VRSF catless ones. I would hope to keep the same performance gains but with less noise. After a couple years driving with mine, the sound is getting a bit much. I know that adding Vibrant resonators would help, but I also heard that in doing so it would make your car smoke which I definitely do not want.
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11-24-2022, 08:22 PM	#2
jwalker87 Major 318 Rep 1,020 Posts Drives: '08 335i, '11 335xi, '01 Z3M Join Date: Jul 2010 Location: Pittsburgh, PA iTrader: (2)	Catless DPs are just tubes - only way you're getting 'quieter' ones are to get ones with cats. I'd either get some high-performance catted DPs or look elsewhere in your exhaust system for ways to tone down the noise a bit. Why would adding resonators make your car smoke? What other modifications to you have to the exhaust (PE mod, etc.)? __________________ 2001 e36/7 M Roadster 5spd 2008 e90 335i 6spd 2011 e90 335xi 6spd 2011 e70 x5 diesel 2010 Ducati Monster 696
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11-25-2022, 09:45 PM	#4
Slim415 Second Lieutenant 92 Rep 281 Posts Drives: 2011 335is 6MT Join Date: Jul 2019 Location: SF, CA iTrader: (0)	Question about the catted DP's. How much of a performance loss is there compared to catless? And it's quieter as well?
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11-25-2022, 11:02 PM	#5
whyzee125 Brigadier General 1662 Rep 3,626 Posts Drives: Dinan stage 2 335i Join Date: Jul 2014 Location: Chattanooga Tn iTrader: (0)	I'm guessing the smoke you're referring to would be the result of deleting the secondaries to replace with the resonators, and not the resonators themselves. A properly running car shouldn't smoke but sometimes aging turbos produce a little smoke that is masked by the cats. I have the PE mod with VRSF catless and with the windows up it could easily pass as stock, just has a bit more buzz/rasp up high at WOT. I would make sure you don't have the golf tee mod or the tune equivalent if applicable and look into catted downpipes. You could expect a few less ponies but I'd be surprised if it's enough to be felt. I've also heard of one member on here who heat wrapped his DPs and claimed it made it just as quiet as the stock ones. His words, not mine, but something that could be worth a try.
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