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Rapid Exhaust - Marriage Savers

The91kwbeast

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BMW M cars with bimodal exhausts are ridiculously loud with the valves open. In Sports+ mode, the valves are permanently open on most and drone like crazy. My wife has an X3 M40i SUV, a 3 litre 6 cylinder turbo and I remember on start up in the show room when collecting the car, it sounded like the exhaust had fallen off the turbo. These are stupidly loud on initial start up to the extent that you'd wake the neighbours starting it up in the middle of the night. Although they're quiet with the valves closed, it's a wonder how they comply when a flick of a switch unleashes a noise level that certainly wouldn't meet noise compliance.
Yes many other makes seem to work that way, and have stupidly loud bi modals exhausts.

Mustang GT, i30N, anything AMG.. I actually thought the act of having a bi modals exhaust is what makes it pass as there is an OEM quiet mode?
 

The91kwbeast

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True car enthusiasts in my 46 years of experience are addicts no different than drug addicts aren't overly concerned with the legality or compliance of the substance they're taking either. In SA for example, you can't have a VF Commodore at the desired ride height, they're too low and will fail a rego inspection. You can't have darker tint than 35 on the front windows where desirable tint starts at 20 and preferably 15's good!. My ute would probably pass a rego inspection for the engine and exhaust but technically doesn't comply with an HSV 340 set up on a MY17 compliance vehicle. HSV 340 compliance ended November 2016. Very difficult in fact to have the desired mods and maintain compliance.
Car enthusiast or car modders?

You can be an enthusiast without being a mod addict, visa versa doesn't apply. Every state does have different rules though which makes it tricky so you need to be informed.

All my cars have had basic mods and all legal, because I appreciated the core car for what it was.

If you want to do more just get the inspection certificate thing you need (in NSW at least)
 

mpower

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"true car enthusiasts" do X.

no.
 

Skylarking

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Yes many other makes seem to work that way, and have stupidly loud bi modals exhausts.

Mustang GT, i30N, anything AMG.. I actually thought the act of having a bi modals exhaust is what makes it pass as there is an OEM quiet mode?
I suspect it’s not the bi-modal itself that makes the vehicle pass noise tests but more the way the legislation is written and the fact the software is tuned to ensure it passes (possibly by detecting a test).

Passing tests is one thing but on the road is a different matter as VW found out later at a cost measured in the multiples of billions…

Whether the regulator has the cajones to take on these car makers and assess whether the software applies a cheat during noise testing phase and behaves differently on the road is something else entirely.

But it does bring up the point whether building your own Bi-modal controller to open or close the valve at will is entirely legit as the vehicle may no longer comply with noise laws… Pity if that’s the case as I like the ability for us to tinker and the work done on a DIY controller is stellar.

Basically it seems international companies can do whatever they like (self regulated to a large extent) but we individuals can be haulled over the coals by your average plod… all seems unfair but it is what it is.
 

RevNev

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You can be an enthusiast without being a mod addict
To be honest, I don't know any "true enthusiasts" like a mate of mine for example put a camshaft in his Maloo Ute last weekend at 69 years old, who aren't addicted to mods. Only concourse restorers leave a car stock yet they'll own other modified cars. Having said that, I know a lot of ex Holden V8 owners who claim to be enthusiasts and now drive Hyundai and Kia SUV's, not sure what level of "enthusiast" I'd classify them?
 

Ginger Beer

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I enthusiastically modify all my cars and bike

I do see some of the people in this forum as whining muppets with nothing better to do than comment on things that don't interest them

Therapy or meditation might help them.....maybe.....
 

RevNev

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I enthusiastically modify all my cars
Me too!. Here's a VE SS wagon diffuser on a VF Ute rear bumper painted in Phantom Black. It's my original tow bar bumper with holes in it worthy of chopping up to see if a diffuser setup worked. I found that mod extremely therapeutic!

20220726_220528.jpg
 

lmoengnr

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Me too!. Here's a VE SS wagon diffuser on a VF Ute rear bumper painted in Phantom Black. It's my original tow bar bumper with holes in it worthy of chopping up to see if a diffuser setup worked. I found that mod extremely therapeutic!

View attachment 240551
A Maloo spare wheel tub does a similar thing on my Magnum... :cool:
 

PeteSS

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Bi modal exhaust systems are controlled by software and with software anything goes… It wouldn’t surprise me if the electronics can determine when test procedures are occurring and thus noise remains within legislated limits but are way over in spirited driving just as the customer likes. And don’t forget some engineering effort as put into the exhaust system the patented hole in the muffler exit pipe (Ballie tip)…

Bi-modal exhausts may ultimately be found to be of a similar cheat to VW who fell neck deep into the poo by using logic to determine test procedures may be occurring and thus ensured pollution stayed within legislated limits while at other times power was the main game…

So, maybe it’s not so much a band aid solution but maybe more a case of complex engineering brought to you by unconscionable management :p:p

As is, I often wonder how AMG can be legal as their cars have a ferociously loud bark on gear changes during WOT take offs but are nice and quiet at other times… sort of goes against the intent of noise laws :rolleyes:

LOL.. my wife drives a Merc C43 and i have no idea how these things passed any noise laws. In sports + mode it is hideously loud.. They must've spent some time on it though, as it doesn't drone at all. Though unlike the rumble of the V8 which i can listen to all day, you an only take the V6 noise in small doses.
 

mpower

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To be honest, I don't know any "true enthusiasts" like a mate of mine for example put a camshaft in his Maloo Ute last weekend at 69 years old, who aren't addicted to mods. Only concourse restorers leave a car stock yet they'll own other modified cars. Having said that, I know a lot of ex Holden V8 owners who claim to be enthusiasts and now drive Hyundai and Kia SUV's, not sure what level of "enthusiast" I'd classify them?

exthusiasts?
 
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