Facelift RS3 Genuine Secondary Cat Bypass Pipes
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You’re right, not sure what the person thought that told me then and he has had it done.
We had an Audi Tech on here a couple of months ago show us underneath a car and state that the UK cars did not have them.
Every person since has said theirs hasn’t got them, the loan car I had with a standard exhaust didn’t.
So who has?
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The PFL does NOT need any cutting to fit Milltek secondary decats. If you feel so inclined, and jack the car slightly, they can be fitted on your drive. Just three bolts at the flange end and a strap clamp at the other - simple. Can also be easily done at the local fitter for a few quid in the hand.
Sound difference on PFL with decat is awesome with OEM sports exhaust switching between dynamic mode, no real drone on motorway. If you are complete bonkers, anti-social or just hate your neighbours, disconnect the valves in the back box too. Cold start is just mental for around 20 seconds! Motorway drone is too much for me with valves disconnected though.
Sound difference on PFL with decat is awesome with OEM sports exhaust switching between dynamic mode, no real drone on motorway. If you are complete bonkers, anti-social or just hate your neighbours, disconnect the valves in the back box too. Cold start is just mental for around 20 seconds! Motorway drone is too much for me with valves disconnected though.
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Dont expect any extra power by just fitting a Milltek secondary decat to a stock power car, in fact with the exception of one car, the dyno results I have seen seem to show a slight drop in torque. However, this can be reversed to your advantage when mapping the car as the improved flow gives the tuner more scope for squeezing a little extra output out of it (note: assuming you are having a custom tune of course).
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Well my fire just well and truly got pi55ed on. Took it to a local mechanic (I don't know him) who refused to fit the pipes for me. Apparently he's an ex Audi tech and doesn't agree with removing things that are going to pollute the earth!
Unfortunately I'm the most mechanically useless person so will struggle to relay what he said, but it was along the lines of the reduced back pressure will mean the turbo spooling up quicker and causing damage, going on to say that they need properly mapping in. All the words like knock and detonation were thrown in there. I'd love to hear some thoughts from our experts like @Aoon_M etc as I just can't believe what he was saying. People have had these bypass pipes on their cars for a long time.
I mentioned that the FL doesn't have the secondary cats and he suggested that will be because the primary cat will be bigger...is this true?
Unfortunately I'm the most mechanically useless person so will struggle to relay what he said, but it was along the lines of the reduced back pressure will mean the turbo spooling up quicker and causing damage, going on to say that they need properly mapping in. All the words like knock and detonation were thrown in there. I'd love to hear some thoughts from our experts like @Aoon_M etc as I just can't believe what he was saying. People have had these bypass pipes on their cars for a long time.
I mentioned that the FL doesn't have the secondary cats and he suggested that will be because the primary cat will be bigger...is this true?
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Real easy to change @D0C took my BIL 30 minutes. Need a ramp though imho as tough to get to unless up in the air.
Not noticed any issues with mine, other than noiseand had them on for about a year.
TX.
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Easy with Trolley jacks and Axel Stands too TX
Likely he is getting confused with the main downpipe, remove that and don't adapt for it with a software update then you can run into all sorts of issues.
Not the case on the secondary pipes though as far as I know, certainly wasn't on the first generation TTRS/RS3 and obviously isn't the case on the facelift that don't have them.
Wouldn't worry about it, any garage will fit them for you.
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Yes mate, had mine running about 420, loved the car but literally everyday was another engine failure so thought better get out of here before the prices really start to drop. Can't wait for the RS3, should be getting it early march!
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I was the same mate... my cars an everydayer so the constant thought of the engine going really took the while RS experience out of it along with the fun
My build date is 22nd Jan at the min so hoping to have it for March too
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Mine originally was the 29ty but jumped forward to the 22nd a week or two back
Nardo Saloon with pretty must everything bar the ceramic brakes... really looking forward to the quality feel of the interior and all the extra gadgets compared to the RS, especially the virtual cockpit
What have you gone for?
Nice, Nardo Saloon as well, most things bar ceramics/sunroof/wheels as will be putting aftermarket wheels on eventually. I think i'm in love with the VC
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Nice, Nardo Saloon as well, most things bar ceramics/sunroof/wheels as will be putting aftermarket wheels on eventually. I think i'm in love with the VC
Sweet! Yea I think the wheel options were the poorest part of the spec list... a nice after market set will add even more to the look, there are a couple of sets of OZ’s I’d love but probably be staying standard for a while! I was sitting in a few cars they had in the dealers and just the quality differences in materials etc is massive
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Its this kind of misinformation that leads people to believe these scaremongering statements in the first place.
Our cars are strictly closed loop boost control.
A turbo is an air pump, if you let the air get in or out easier, it increases the efficiency of the pump. By removing cats, you let the air get out easier. The car doesn't just apply say 50% power to the turbo and hopes for the best, the ECU is a a lot smarter than that. So to those thinking by removing cats you can damage the turbo by making unwanted power without a map etc or run into issues are plain and simply wrong.
The way the ECU works in "closed loop mode" is simple. It reads the voltage off the map sensor on the manifold, and it constantly adjusts how much power to send to the turbo by dynamically adjusting the wastegate. It does this by having a target boost level set in the ECU, and constantly aims to hit that target regardless of how much or how little turbo it needs to use (to an extent).
This is why, removing cats, increasing the efficiency of the car cannot possibly damage anything. Closed loop boost control will not allow it.
There are two sensors on the main catalyst, one is pre cat and one is post cat.The pre cat sensor is responsible for managing the air to fuel ratio (AFR) which is unaffected whether you are running a catalyst or not. The post cat sensor is responsible for checking if the main cat is actually working. That is all.
By removing the main cat, you will end up with an engine management light unless mapped out. Nothing else. Hope that clears that up.
Now the secondary cats on the car have no sensors on or around them, by removing them once again just like the main cat you will achieve nothing other than more sound and increased emissions. The secondaries are rather unrestrictive 300 CELL cats, we recently mapped a car to stage 2 and removed the main cat, but left the secondary cats in place - this car made excellent power and torque, the torque figure exceeding that of a fully decatted car actually.
The secondary catalysts on the car are not noise silencers or back pressure increasers or any other rubbish people will tell you, they are simply there to reduce the emissions of the car. It is that simple. you don't risk any damage whatsoever to anything by removing them, other than old peoples ears. Neither will they trigger an engine management light under any circumstance.
The facelifts have done away with the secondary cats altogether, instead they have a huge main cat, this has been made possible due to smaller turbo tech and leaving a lot more room in the bay for a larger cat. Some countries have stricter emissions standards than others however, hence why some facelift cars come with secondary cats and some don't, UK cars don't, if you are doubtful you can check whether your car has them or not by checking underneath the car or reading the servicing timeline card that came along with the manual etc of your car, there will be a page on the front with a white label full of PR codes and you will have either or below;
Bypass pipes - 7MU Emission standard LEV 3/Tier 3 125
Catalyst pipes -7GH = Emission standard EU4 without EOBD without hardware modification, 7MM = Emission standard EU6 plus
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I had an Impreza P1 about 15yrs ago, fully decatted the car and the turbo would overspool and flames would come out it’s ar*e end. Ran like a bag of sh*t until I had it tuned. More recently, about 5yrs ago on a stock TTRS, gutted the main downpipe, drove around with it for a few hundred miles on an EML light, thought the car had lost something from the butt dyno test, took it 400 miles down to MRC to be tuned and my stock TTRS was running 326ps as opposed to the 340+ it should have had. Mihnea tuned it to stage 2 and out popped 428ps. No issues at all on the car. The gutted downpipe certainly never increased the power I had before adaptation anyway. M
That’s real life experience. I wouldn’t expect to remove the downpipe on this RS3 at the moment, run it unadapted and for the car to run better with more power. The ecu will still be running from the stock requested boost and ignition tables. It needs a tune to change that. Audi have spent a lot of time tuning the engine with stock hardware, closed loop or not, change something in that setup, the ecu will have to try to adapt. Look what happens when you run different intakes, some aftermarket kits actually lose you power before anything is rewritten in the ECU
Secondary cat pipes, yes, they are there to reduce emissions but there is a clear noise gain from them when you bypass them hence why some people state they are nothing but noise suppressors.
That’s real life experience. I wouldn’t expect to remove the downpipe on this RS3 at the moment, run it unadapted and for the car to run better with more power. The ecu will still be running from the stock requested boost and ignition tables. It needs a tune to change that. Audi have spent a lot of time tuning the engine with stock hardware, closed loop or not, change something in that setup, the ecu will have to try to adapt. Look what happens when you run different intakes, some aftermarket kits actually lose you power before anything is rewritten in the ECU
Secondary cat pipes, yes, they are there to reduce emissions but there is a clear noise gain from them when you bypass them hence why some people state they are nothing but noise suppressors.
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Moving on, just read your rant about Milltek there.
Other than the Iroz downpipes, are you aware of any other solutions for the facelift cars? Contacted Iroz about their downpipe but they try and sell you it as a kit with the secondary pipes (US has the secondary cats) and not sure if their downpipe will therefore mate up to the stock UK system without modification work to the connections.
Seemed too pricy to bring it to the UK too, shipping and import charges were making it £1k alone for a downpipe, about 60% more than what you would expect to pay in the UK from the likes of Milltek or Scorpion.
Other than the Iroz downpipes, are you aware of any other solutions for the facelift cars? Contacted Iroz about their downpipe but they try and sell you it as a kit with the secondary pipes (US has the secondary cats) and not sure if their downpipe will therefore mate up to the stock UK system without modification work to the connections.
Seemed too pricy to bring it to the UK too, shipping and import charges were making it £1k alone for a downpipe, about 60% more than what you would expect to pay in the UK from the likes of Milltek or Scorpion.
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Downpipes are a whole 'nother story!
I had both Milltek and Scorpion downpipes on my pre facelift car, the Milltek spent all of its life rubbing on the propshaft and the Scorpion downpipes brackets down towards the section where it connects to the secondaries are made of .5mm sheet aluminium, the brackets ripped apart after two weeks of use and then that downpipe also spend the rest of its life rubbing against the firewall/centre tunnel.
I now have/had the APR Cast downpipe on my car and it is the best fit and quality out of any other downpipes I have ran, and when you take into account it was designed for the TTRS 8J, it's really quite questionable why the Milltek and Scorpion offerings are so poor in comparison.
My advice to you would be to either gut the cat out of your own stock downpipe or get another stock downpipe and have it gutted. Let me know if you need a hand sourcing one. It is the route I will go down if I decide to mess about with the stock turbo on the 2.5 EVO engine. Or I would take APR's offering as their hardware is unmatched in the industry, but they haven't released a downpipe yet.
Personally I don't think the stock downpipe when gutted is restrictive, Sören's TTE625 car (iron block 5 cylinder) made stated turbo power all whilst running the standard downpipe
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Also their downpipe offering would work fine on UK cars, the catback systems are identical on UK/US cars. If you take a look at the milltek downpipe for the pre facelift rs3 8v it is very similar to that
Hi Aoon,
Yes, certainly would consider gutting a standard Audi downpipe. God knows where I would find one though at this early stage. Direct from Audi will be a no no due to the cost of the Cat, 2nd hand, yes, definitely. Might have to scour the US eBay as those that are fitting the Iroz downpipes will have theirs going spare. If you do find something just fire me a PM, appreciated.
Yes, certainly would consider gutting a standard Audi downpipe. God knows where I would find one though at this early stage. Direct from Audi will be a no no due to the cost of the Cat, 2nd hand, yes, definitely. Might have to scour the US eBay as those that are fitting the Iroz downpipes will have theirs going spare. If you do find something just fire me a PM, appreciated.
This video has the RS3 FL with IMS DP/MP and stock catback. In the comments the owner says: 'you don’t have to tune for it. The car actually runs better with it then with the stock one. You will get an occasional CEL though. I’m tuning next week though so CEL won’t be an issue any longer.'
For those commenting on here with PFL’s, I am selling my AWE Tuning Switchpath Valve Controller which is in the classifieds, it won’t fit the FL.
http://www.awe-tuning.com/switchpath-exhaust-remote
http://www.awe-tuning.com/switchpath-exhaust-remote
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Connectors on the valves are different I noticed this a few weeks back, if you wanted to keep the controller it would only be a few quid to re pin the connectors to the right plugs - easy task as vag connectors are very simple to work with
Yep I had my controller all tied up when I realised, really annoying.
There is an extra pin on the new plugs though? Surely it is there for a purpose and therefore my controller will be missing a core?
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