RS3 Exhaust 'stuff'

[Mike.46]

Ive picked up on a few people saying that the exhaust tips are 'fake' and indeed they are no longer connected to the rear silencer, but there again that is exactly the same as on Audi's flagship R8 models from 2008 onwards It allows closer and more accurate fitment of the tail pipes to the rear bumper

The valves in the Sport exhaust are also now constantly variable and not either open or closed (JFI an R8 has them open at idle, they close at 1500rpm and reopen at 4500rpm or full throttle) A company called Kufatec supply a system (for other models) that is controlled by your phone, either Open/Closed/Auto here : https://www.kufatec.com/en/valve-co...i-s3-8v-rs3-8v-ttrs-8s-with-app-control-43909
No RS3 8Y fitment yet but I imagine in time it will follow

 

[Keano04]

I’ve recently seen pcw offer some sort of exhaust mod or something for the rs3 but can’t find any info for it…

Ie what they do and what it would cost?

 

[billymc92]

I’ve recently seen pcw offer some sort of exhaust mod or something for the rs3 but can’t find any info for it…

Ie what they do and what it would cost?

Cuts them open and modifys it. He’s £300

 

[Adam28]

Cuts them open and modifys it. He’s £300

does this void warranty ?

 

[HulkRS3]

does this void warranty ?

It's a hard subject to touch upon. If they could prove that the modification led to the failure of whatever component went then yes. Usually only affects the warranty on that part.

 

[Alan Oliver]

100% I'd imagine

 

[Adam28]

It's a hard subject to touch upon. If they could prove that the modification led to the failure of whatever component went then yes. Usually only affects the warranty on that part.

any updates on your car mate, I only logged back in after a few months rather have it sounding like a hoover for the time being

 

[HulkRS3]

any updates on your car mate, I only logged back in after a few months rather have it sounding like a hoover for the time being

hahah welcome back! yes - it's at the port of exit waiting to be shipped

 

[billymc92]

 

[Keano04]

Cuts them open and modifys it. He’s £300

I will be doing this at some point as there’s no harm in a little more noise eh.

I did contact him but not had a reply. Will follow up again another time perhaps

 

[Terminator x]

^^ he gets so many calls that he prefers a text which he then answers at night one by one.

TX.

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[Keano04]

Having lived with mine for nearly 2k miles, and whilst it will likely bed in a little further, I think the exhaust does need a booster.

Will be looking into modding the exhaust now so will reach out to that chap again…

 

[Mike.46]

I strongly suspect that even the sport exhaust does not do what you think, for starters reading the manual suggests the programme reverts back on start up to quiet mode (says something about double pressing the selection of drive mode) and I have also noticed that in say Performance mode the exhaust note is quite loud in neutral but once D is selected it goes quieter.

I started this thread with a link to a Kufatec device that says the exhaust flaps are active and open/close to different positions, the Kufatec device keeps them open all the time.

BMW M4 has similar, the lads there unplug the actuators whilst the valves are open, makes them much louder but resonate at certain speeds/rpm, whether unplugging the actuators wouls work the same I dont know, but best have someone handy with VCDS/OBD11 to clear any poss dash lights

 

[HulkRS3]

I strongly suspect that even the sport exhaust does not do what you think, for starters reading the manual suggests the programme reverts back on start up to quiet mode (says something about double pressing the selection of drive mode) and I have also noticed that in say Performance mode the exhaust note is quite loud in neutral but once D is selected it goes quieter.

I started this thread with a link to a Kufatec device that says the exhaust flaps are active and open/close to different positions, the Kufatec device keeps them open all the time.

BMW M4 has similar, the lads there unplug the actuators whilst the valves are open, makes them much louder but resonate at certain speeds/rpm, whether unplugging the actuators wouls work the same I dont know, but best have someone handy with VCDS/OBD11 to clear any poss dash lights

I've noticed what you're referring to between D / N / S - I think when it goes louder in N is to give you a bit more of an 'experience' sound, and when you go to D it gives you more of an organic sound. S obviously has a higher resting rev threshold so that sounds decent too. What we really need is the car to sound like it does on a cold start.

 

[8YARWY]

I strongly suspect that even the sport exhaust does not do what you think, for starters reading the manual suggests the programme reverts back on start up to quiet mode (says something about double pressing the selection of drive mode) and I have also noticed that in say Performance mode the exhaust note is quite loud in neutral but once D is selected it goes quieter.

I started this thread with a link to a Kufatec device that says the exhaust flaps are active and open/close to different positions, the Kufatec device keeps them open all the time.

BMW M4 has similar, the lads there unplug the actuators whilst the valves are open, makes them much louder but resonate at certain speeds/rpm, whether unplugging the actuators wouls work the same I dont know, but best have someone handy with VCDS/OBD11 to clear any poss dash lights

If they are same as the 8V it pulls power higher up the range when it detects the valves aren’t working.


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[Terminator x]

If they are same as the 8V it pulls power higher up the range when it detects the valves aren’t working.


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Cete valve controller would auto control the valves open and shut to prevent that. I really liked mine (mostly as it remembered open / shut even after an ignition cycle) although I appreciate some people had issues with theirs.

TX.

 

[8YARWY]

Cete valve controller would auto control the valves open and shut to prevent that. I really liked mine (mostly as it remembered open / shut even after an ignition cycle) although I appreciate some people had issues with theirs.

TX.

Yes that’s a way around it. I had one until I remapped the car.


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[HulkRS3]

Kufatec offered to give me a unit for free if I took the car to Germany for a day. Sadly would’ve cost me more to get there but an offer for someone if you want to reach out

 

[8YARWY]

May order this.

Active Valve Control Profil-Based Control / Audi RS3 8Y / right-hand steering (RHD)

Most important details Better sound due to highquality goods No external buttons needed – easy handling with already available buttons Plug&Play fast and easy installation

www.active-sound.eu

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[Mike.46]

^ Thats a good find, expensive though

 

[Keano04]

Given the difficulties with opf removal, is there a lighter option to fit a modified opf so you get more flow/noise but still retain some filter capabilities so the ecu doesn’t throw a wobbly?

I’m thinking like fitting a sports-cat but a sports-opf?

In the past I’ve modified the down pipe on a car to remove part of the cat so that the noise went up but emissions weren’t an issue as it was still doing “enough” to keep the ecu happy…

Doing similar with the opf may be a good way of coming up with a stealthy improvement to noise without the headaches?

 

[8YARWY]

Given the difficulties with opf removal, is there a lighter option to fit a modified opf so you get more flow/noise but still retain some filter capabilities so the ecu doesn’t throw a wobbly?

I’m thinking like fitting a sports-cat but a sports-opf?

In the past I’ve modified the down pipe on a car to remove part of the cat so that the noise went up but emissions weren’t an issue as it was still doing “enough” to keep the ecu happy…

Doing similar with the opf may be a good way of coming up with a stealthy improvement to noise without the headaches?

I’m waiting until they release the pressure sensor bypass modules that actually work, similar to Joe Achilles has used.


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[Keano04]

I’m waiting until they release the pressure sensor bypass modules that actually work, similar to Joe Achilles has used.


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I was thinking about it from a slightly different angle to create a stealth-opf mod so from under the car you would t know it’s modified as the opf(s) would still be there…

Wouldn’t be any issues with warranty etc as to a tech they would look oem as per the factory.

 

[8YARWY]

I was thinking about it from a slightly different angle to create a stealth-opf mod so from under the car you would t know it’s modified as the opf(s) would still be there…

Wouldn’t be any issues with warranty etc as to a tech they would look oem as per the factory.

It’s all in one piece though………

How are you going to gut the OPF ?


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[Keano04]

It’s all in one piece though………

How are you going to gut the OPF ?


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Cut it open, mess around a bit with the innards, weld it back up again and fit it.

I’ve messaged that PCW exhausts chap to see if he fancied giving it a go…

Once the first is done, would be a nice little money earner if he did a load and offered them on an exchange basis.

Had something similar (pre opf so was done on an oem cat) on a previous car. These are some pics from when it was done on a previous cars down pipe/cat.

 

[8YARWY]

Cut it open, mess around a bit with the innards, weld it back up again and fit it.

I’ve messaged that PCW exhausts chap to see if he fancied giving it a go…

Once the first is done, would be a nice little money earner if he did a load and offered them on an exchange basis.

Had something similar (pre opf so was done on an oem cat) on a previous car. These are some pics from when it was done on a previous cars down pipe/cat.

You do realise how big a job it is to get the Main Cat, let alone the one with OPFs attached to it, out…… on the 5 cylinder ?




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[Keano04]

You do realise how big a job it is to get the Main Cat, let alone the one with OPFs attached to it, out…… on the 5 cylinder ?




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Nope

If considering opf delete anyway isn’t that a moot point?

Modifying the back box does nothing so that’s a bridge you’d need to cross whether going opf delete or modified opf…

For context, the above modified cat cost me under £100… labour charges are what they are for taking off/putting on the opf regardless if it’s delete/modified… far cheaper than a new back box that does very little…

 

[8YARWY]

Nope

If considering opf delete anyway isn’t that a moot point?

Modifying the back box does nothing so that’s a bridge you’d need to cross whether going opf delete or modified opf…

For context, the above modified cat cost me under £100… labour charges are what they are for taking off/putting on the opf regardless if it’s delete/modified… far cheaper than a new back box that does very little…

Most would cut the pipes I bet (like a golf R res delete mod) That way it’s at least reversible without having to take half the car apart, and not every garage is capable of carden shaft removal without knackering the centre bearing.

Plus then it would need all re-instating for the next owner, because come MOT time it’ll be a fail, and they’ll have a big bill to rectify it back to a legal standard.


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[Daggerit]

You could easily alter the pressure right at the secondary sensor to fool it into thinking there's an OPF still in place by tapering down the pipework there and create a venturi effect. That would fool the sensor without putting any actual barrier in place but it would still create a bit of a restriction. The other thing you'd need to know is just how much of a pressure drop it was expecting to see so that the calculations could be done.

If the pressures can be measured with VCDS or something then I could come up with some sizing and see if it's possible without choking it too much.

 

[Daggerit]

And just a follow up, it looks like it would be a taper down to about 30 mm (with a lot of assumptions because I don't know the pressures or the estimated flow rate) and a 72 mm long tapered lead down into that. That should give minimal pressure drop overall and minimise back pressure but still fool the sensor.

 

[Mike.46]

You could easily alter the pressure right at the secondary sensor to fool it into thinking there's an OPF still in place by tapering down the pipework there and create a venturi effect. That would fool the sensor without putting any actual barrier in place but it would still create a bit of a restriction. The other thing you'd need to know is just how much of a pressure drop it was expecting to see so that the calculations could be done.

If the pressures can be measured with VCDS or something then I could come up with some sizing and see if it's possible without choking it too much.

I suspect that 'might' work in theory, but, the ecu 'may' also be looking for a change in values coming from the pressure sensors as the OPF does it's work when a regen is required, an OPF pressure signal that does not alter after a regen could be flagged by the ecu (just depends how much trouble and sophistication they have gone to)

 

[Daggerit]

I suspect that 'might' work in theory, but, the ecu 'may' also be looking for a change in values coming from the pressure sensors as the OPF does it's work when a regen is required, an OPF pressure signal that does not alter after a regen could be flagged by the ecu (just depends how much trouble and sophistication they have gone to)

Could well be. I would like to think that it wouldn't ever initiate a regen if it thinks that the OPF is running happily within a high efficiency range, but that's not really guaranteed.

 

[Keano04]

Most would cut the pipes I bet (like a golf R res delete mod) That way it’s at least reversible without having to take half the car apart, and not every garage is capable of carden shaft removal without knackering the centre bearing.

Plus then it would need all re-instating for the next owner, because come MOT time it’ll be a fail, and they’ll have a big bill to rectify it back to a legal standard.


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The point of the partial removal/modification is you wouldn’t need to reverse it and it wouldn’t be an mot fail…

When done to the previous car it got through mot fine so there was no need to reverse it. Opf removal you would have issues at mot like you say of course.

If the “right” amount of the filter material could be removed it would be fit and forget in terms of mot and warranty… what the right amount of material would be I don’t know - the first one is the hardest as it’s a bit of an unknown but if a garage were to take it on and figure it out, it could be fairly lucrative.

 

[Keano04]

Most would cut the pipes I bet (like a golf R res delete mod) That way it’s at least reversible without having to take half the car apart, and not every garage is capable of carden shaft removal without knackering the centre bearing.

Plus then it would need all re-instating for the next owner, because come MOT time it’ll be a fail, and they’ll have a big bill to rectify it back to a legal standard.


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The point of the partial removal/modification is you wouldn’t need to reverse it and it wouldn’t be an mot fail…

When done to the previous car it got through mot fine so there was no need to reverse it. Opf removal you would have issues at mot like you say of course.

If the “right” amount of the filter material could be removed it would be fit and forget in terms of mot and warranty… what the right amount of material would be I don’t know - the first one is the hardest as it’s a bit of an unknown but if a garage were to take it on and figure it out, it could be fairly lucrative.

 

[Mike.46]

Did I read somewhere that the 8V OPF delete did not work on the 8Y ? and that Billymc car was ok at first and then a couple of hundered miles later 'on' pops the engine light? modrn ecu's are getting clever'r and more sophisticated propbably even more so with VW group 'Diesel gate' stuff as well.

A friends A4 2.0TDI threw a hissy fit over the ad blue, turned out (I think) he had over filled the tank by not using the Audi filler neck and although all the temperatures looked ok within the ecu the radar (or untrasonic?) level gauge (yes that exact!) within the tank could not detect the level falling he got a warning basically ''Take me to a dealer within 150 miles or i'm stopping''

 

[8YARWY]

Did I read somewhere that the 8V OPF delete did not work on the 8Y ? and that Billymc car was ok at first and then a couple of hundered miles later 'on' pops the engine light? modrn ecu's are getting clever'r and more sophisticated propbably even more so with VW group 'Diesel gate' stuff as well.

A friends A4 2.0TDI threw a hissy fit over the ad blue, turned out (I think) he had over filled the tank by not using the Audi filler neck and although all the temperatures looked ok within the ecu the radar (or untrasonic?) level gauge (yes that exact!) within the tank could not detect the level falling he got a warning basically ''Take me to a dealer within 150 miles or i'm stopping''

I spoke to Peron Automotive today……..

“Any material removal from OPF filters will 110% cause an ECU error”


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[Keano04]

I spoke to Peron Automotive today……..

“Any material removal from OPF filters will 110% cause an ECU error”


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Had they tried it already?

Well that kills that idea then.

 

[Terminator x]

For all the modders we also have this "you can't mod your car" law coming soon ...

https://petition.parliament.uk/petitions/600954

TX.

 

[8YARWY]

Had they tried it already?

Well that kills that idea then.

They have a bespoke exhaust side to the business, was there a year back when I went on their rolling road.
Very knowledgable guys, do / supply a lot of parts to Hank.


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[Keano04]

For all the modders we also have this "you can't mod your car" law coming soon ...

https://petition.parliament.uk/petitions/600954

TX.

***

Unbelievable

Wonder how far reaching that would be… the wording seems deliberately vague as a catch all too.