Facelift Decat

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JamesCrs3

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Anyone around the midlands have a decatted FL RS3 with the audi sports exhaust cat-back? I'm really interested to hear what the drone levels are like with this setup.

I had a full scorpion turbo-back fitted but because of the ticking noise from the wastegate and the immense drone it was a nono for me, so I had the cat put back in.

The sound level with just scorpion cat-back in is still very loud, and it sounds near damn perfect, there is still some drone but it's nowhere near as bad as the full system.

I could probably live with the wastegate ticking noise but I'd want the drone levels reasonable for daily driving.
 
but why cant you just put it in comfort for daily driving? mines is like standard when in comfort and great for normal driving {or the girlfriend in the car}
 
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billymc92 said:
but why cant you just put it in comfort for daily driving? mines is like standard when in comfort and great for normal driving {or the girlfriend in the car}
Click to expand...

Billy didn’t you have that nasty noise with the stock exhaust? Totally defeating the object of what the op has asked?
 
billymc92 said:
but why cant you just put it in comfort for daily driving? mines is like standard when in comfort and great for normal driving {or the girlfriend in the car}
Click to expand...
There was still a huge amount of drone in comfort mode when I had the complete system on, and I mean like 2-3k rpm going up a slight incline you could actually feel pressure on your ears, it was bad. Now with the cat in it's not too bad, it's the non res cat-back so there is still a bit of drone. Just wanted to know how bad the drone is with a decatted standard system.
 
JamesCrs3 said:
There was still a huge amount of drone in comfort mode when I had the complete system on, and I mean like 2-3k rpm going up a slight incline you could actually feel pressure on your ears, it was bad. Now with the cat in it's not too bad, it's the non res cat-back so there is still a bit of drone. Just wanted to know how bad the drone is with a decatted standard system.
Click to expand...

God that sounds bad, mines is virtually silent in comfort until 4K revs when the valves open. Can’t hear any engine sound inside the cabin.

I obviously had the decat fitted with standard exhaust for 3 months until the catback got released. The car sounded epic. I think it was the perfect note. The ONLY reason I continued to get the back box was as I thought it was going to get rid of the ticking.
 
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billymc92 said:
God that sounds bad, mines is virtually silent in comfort until 4K revs when the valves open. Can’t hear any engine sound inside the cabin.

I obviously had the decat fitted with standard exhaust for 3 months until the catback got released. The car sounded epic. I think it was the perfect note. The ONLY reason I continued to get the back box was as I thought it was going to get rid of the ticking.
Click to expand...
Yeah, the standard exhaust has a perfect note to it. My plan was just decat with audi aports exhaust but got deal on full system ans like you hoped it would clear up the issues. I'm just gonna keep this cat-back system on for now as it does sound really nice. Suppose will just have to buy a tte625 and then go decat haha.
 
audi upgrades
Not sure a TTE625 will solve the issue. It is the stock turbo afterall. I messaged Simon at TTE to ask and he blamed the noise on the exhaust valves so doesn’t look like he’s even aware of the issue with the wastegate.
 
Leo-RS said:
Not sure a TTE625 will solve the issue. It is the stock turbo afterall. I messaged Simon at TTE to ask and he blamed the noise on the exhaust valves so doesn’t look like he’s even aware of the issue with the wastegate.
Click to expand...
Yeah true, have to be a big turbo then.
 
Leo-RS said:
Not sure a TTE625 will solve the issue. It is the stock turbo afterall. I messaged Simon at TTE to ask and he blamed the noise on the exhaust valves so doesn’t look like he’s even aware of the issue with the wastegate.
Click to expand...

Oh I did not know this
 
JamesCrs3 said:
Anyone around the midlands have a decatted FL RS3 with the audi sports exhaust cat-back? I'm really interested to hear what the drone levels are like with this setup.

I had a full scorpion turbo-back fitted but because of the ticking noise from the wastegate and the immense drone it was a nono for me, so I had the cat put back in.

The sound level with just scorpion cat-back in is still very loud, and it sounds near damn perfect, there is still some drone but it's nowhere near as bad as the full system.

I could probably live with the wastegate ticking noise but I'd want the drone levels reasonable for daily driving.
Click to expand...
JamesCrs3 said:
Anyone around the midlands have a decatted FL RS3 with the audi sports exhaust cat-back? I'm really interested to hear what the drone levels are like with this setup.

I had a full scorpion turbo-back fitted but because of the ticking noise from the wastegate and the immense drone it was a nono for me, so I had the cat put back in.

The sound level with just scorpion cat-back in is still very loud, and it sounds near damn perfect, there is still some drone but it's nowhere near as bad as the full system.

I could probably live with the wastegate ticking noise but I'd want the drone levels reasonable for daily driving.
Click to expand...

I don’t think there’s much of a change if any in the comfort drive mode with regards to a constant drone. I haven’t noticed it.

What I have noticed is the cold start rattle is there for about a minute now (on cold start) before dying down. It was about half a minute before the decat. Also the part throttle (25%+ I would say) has the cold rattle sound constantly until you go past about 75% throttle. On full WOT it’s not noticeable and the part throttle is less noticeable when the car is in Sports and Dynamic. I can only hear it when I have the music in the car switched to off and I’m listening out for it. However, I’m sure on the outside, to passers by, it sounds like something is broken.

Still, even though it does this, it’s not enough for me to want to put the standard downpipe back in. The noise difference on WOT is superb, it sounds proper angry. There’s more crackles and pops for sure too. There’s definitely a performance benefit even on the standard map (but I haven’t measured this yet)

In addition, I really need to see what it sounds like when it’s tuned and if MRC can do anything about the rattle. I know they can pretty much turn the cold start map off so that will definitely help. I’ll have a word with Doug to see how much he can disguise it.

Bit of a pain and looks like it’s just going to have to be accepted if tuning this engine. Can’t see an easy fix for it other than swapping out the turbo.
 
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The rattle now lasting 60 seconds rather than 30 seconds is no surprise. I've noticed the cold start noise dies down initially after approx 30 seconds but then it's another minute or so till the revs drop from 11-1200rpm to 750rpm.

Will watch with interest to see what MRC can do about the rattle. Audi must surely recognise the car sounds like a bag of spanners at low revs the way it is now.
 
D0C said:
The rattle now lasting 60 seconds rather than 30 seconds is no surprise. I've noticed the cold start noise dies down initially after approx 30 seconds but then it's another minute or so till the revs drop from 11-1200rpm to 750rpm.

Will watch with interest to see what MRC can do about the rattle. Audi must surely recognise the car sounds like a bag of spanners at low revs the way it is now.
Click to expand...


The start up rattle sounds worse in a garage or confined space.

When the car is in the Audi Work shop it’s a lot harder to hear it.

I’ve done several video recordings of the Wastegate Actuator rod on cold start and it doesn’t move at all.

Even putting my hand on the rod and moving it so the waste gate opens does nothing to alter / stop the start up rattle.

The other day mine didn’t rattle upon cold start but weirdly the rattle faded back in after 10 secs then stopped at 30 secs.
 
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