Scorpion Cat Bypass pipes finally fitted

Mr_Freeze

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Lightning got her first upgrade!

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​Tidy job. :) x
 
Did you have to remap having removed cats? And what kind of power gain does this give?

Regards Bob
 
Proper job Neil, I'll post this now for others...

1) Using a 13mm ring spanner carefully remove the 6-nuts holding the cat-pipes to the down pipes

Make sure to spray the studs with WD40 or similar lubricant as the studs are mild steel and secured to the cat-pipes

2) Using a 13mm ring spanner release the 4-nuts from the connecting-sleeves securing the cat-pipes to the primary silencer

3) Carefully slide each connecting-sleeve forward and onto its respective cat-pipe

4) Carefully remove both cat-pipes with the gaskets and the connecting sleeves

5) Carefully remove the metal gaskets from the cat-pipes: use a thin broad blade or similar so as not to damage the gaskets

6) You'll have noticed that the nuts on the connecting-sleeves were uppermost when you removed them; this is not good engineering practice as if the nut were to unscrew then the likelihood is that you'd loose both the nut and the screw so, when refitting, change the connecting-sleeves over so that the nuts are on the underside (hope this makes sense…)

7) Slide the original nearside connecting-sleeve onto the offside bypass pipe (securing nuts down)

8) Using the original metal gasket without sealant, assemble the offside bypass pipe to the offside down pipe: use stainless steel nuts and bolts where possible and make sure to coat the threads of ALL bolts with Copperslip or similar anti-seize grease

9) Slide the connecting-sleeve on to the offside primary silencer pipe and pinch tighten both nuts and bolts (make sure you've applied Copperslip to the threads)

10) Keep checking the alignment and tighten all 5-nuts and bolts to complete

11) Use exactly the same procedure (7 to 10) and assemble the nearside bypass pipe

12) Double check alignments and tightness of the fastenings

The tools:

 
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Did you have to remap having removed cats? And what kind of power gain does this give?

Regards Bob

No remap needed as the sensors are before the cat's.

I will report back how she feels after a few days driving.

The power gains are not expected to be much maybe realistically a couple at most, silly figures of 10-15bhp would be silly.

Others report the car rev's more freely and of course it will growl just a little deeper when pushed.

Going out to play :jester:
 
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Great job that john and mr_freeze :)
 
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Proper job Neil, I'll post this now for others...

1) Using a 13mm ring spanner carefully remove the 6-nuts holding the cat-pipes to the down pipes

Make sure to spray the studs with WD40 or similar lubricant as the studs are mild steel and secured to the cat-pipes

2) Using a 13mm ring spanner release the 4-nuts from the connecting-sleeves securing the cat-pipes to the primary silencer

3) Carefully slide each connecting-sleeve forward and onto its respective cat-pipe

4) Carefully remove both cat-pipes with the gaskets and the connecting sleeves

5) Carefully remove the metal gaskets from the cat-pipes: use a thin broad blade or similar so as not to damage the gaskets

6) You'll have noticed that the nuts on the connecting-sleeves were uppermost when you removed them; this is not good engineering practice as if the nut were to unscrew then the likelihood is that you'd loose both the nut and the screw so, when refitting, change the connecting-sleeves over so that the nuts are on the underside (hope this makes sense…)

7) Slide the original nearside connecting-sleeve onto the offside bypass pipe (securing nuts down)

8) Using the original metal gasket without sealant, assemble the offside bypass pipe to the offside down pipe: use stainless steel nuts and bolts where possible and make sure to coat the threads of ALL bolts with Copperslip or similar anti-seize grease

9) Slide the connecting-sleeve on to the offside primary silencer pipe and pinch tighten both nuts and bolts (make sure you've applied Copperslip to the threads)

10) Keep checking the alignment and tighten all 5-nuts and bolts to complete

11) Use exactly the same procedure (7 to 10) and assemble the nearside bypass pipe

12) Double check alignments and tightness of the fastenings

The tools:



The easier option is to go down to Cannock to see a certain John and let him do it, just make sure you have a couple of litres of Sangiovese fuel with you.:lmfao:

BEWARE : avoid stepping on his toes while is doing the work , sorry I meant watch out for flying spanners...
 
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Thank you Vito for your kind words...

PS, my 1972 Lotus Europa did sell yesterday and will soon be off to a very good family and home just South of AUDI UK...

Is it me?
 
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John did graciously offer to do the swap over for me, but due to the distance involved i found a local alternative.

I feel that at some point in the future i will make the trip to casa del Bluey, if for nothing else but to check out his garage, but not this weekend,
 
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Well i had a nice little drive yesterday that involved a spirited section or 2.

I don't know whether this is just a physcological response to the extra sound, but it definately feels like it rev's better, more crisper and slightly faster (Again it could be just in my head........Mark step in anytime and disect me).

So round town, no real noticable difference, but open her up and a definate deeper growl and a more pronounced "BRRRUUPP" on the upshift when pressed hard.

Verdict, not an expensive option but gives a pleasing result. VFM.
 
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Well i had a nice little drive yesterday that involved a spirited section or 2.

I don't know whether this is just a physcological response to the extra sound, but it definately feels like it rev's better, more crisper and slightly faster (Again it could be just in my head........Mark step in anytime and disect me).

So round town, no real noticable difference, but open her up and a definate deeper growl and a more pronounced "BRRRUUPP" on the upshift when pressed hard.

Verdict, not an expensive option but gives a pleasing result. VFM.

Oh yes! Yes, yes, yes!

Same on mine Neil, even Moschops said the same while driving mine (BLUEY)...

Uncanny for a turbo/inter-cooled engine but it does seam to breath better/freer somehow.

As for the noise, best not go there as I'm still utterly besotted by the noise both up and down the box…

And thank you for your kind words too…
 
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Yes I agree Neil, having driven Bluey the other week, it breathes more easily and sounds nice on the upshift..:w00t:

Do i or don't i.......Hmmmmmm:think:
 
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Well i had a nice little drive yesterday that involved a spirited section or 2.

I don't know whether this is just a physcological response to the extra sound, but it definately feels like it rev's better, more crisper and slightly faster (Again it could be just in my head........Mark step in anytime and disect me).

So round town, no real noticable difference, but open her up and a definate deeper growl and a more pronounced "BRRRUUPP" on the upshift when pressed hard.

Verdict, not an expensive option but gives a pleasing result. VFM.

I'm completely positive about the secondary decat pipes. I think there are two different things to think about. One is effect (what the mod does) and the other id affect (how the mod changes how you think and drive).

Effect - almost certainly some reduction in back pressure from the turbo and enough to feel a little more throttle response for sure. More performance, probably a small increase with learning ECUs and all that. There is more growl and deeper roar with decat pipes. We heard several pass from the side of the road at the meet and it's a noticable difference, well within the normal range of exhausts and at the same time good.

Affect - I think the added sound has a big influence on how you drive and how you feel about the drive. You like the sound and so you want to experience it more often. That in turn gives you more reason to enjoy the car. The sound makes you feel like you are going faster (you may well be). As a result you enjoy the car more...

All in all a great mod for a reasonable price.
 
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Full milltek is 2k plus so id say the scorpion is around that price ,could be cheaper ..
 
Cheers RS3-KEL

Do you trust the figures? I would have thought that stock is a bit higher to start with. If it's really 30-40bhp, that's good as there is no remap and potentially no warranty issues?

And does the full line push the car to the next emission tax band?
 
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This is the list price of their kit. Most retailers will offer you between 10 -15% off.

As you will see the full systems are recommended that a remap take place due to management light been activated, so i would assume its more than just a system change to get to the quoted figure..

The comment is however wrong regarding the Cat Bypass pipes, as the management light is not activated.

Scorpion list price
 
I am glad you lot have seen the light with the secondary CAT bypass.... :w00t: I feel somewhat responsible :yes:
 
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I am glad you lot have seen the light with the secondary CAT bypass.... :w00t: I feel somewhat responsible :yes:

Just ordered the pipes - due delivery Friday, fitting next Wednesday. Thanks for the detailed instructions John! Looking forward to the results of my first mod...

Not notified the insurer yet - any experience with DL?
 
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Pipes fitted today, brilliant mod! Much better note! On both up and downshifts!!
 
So, a question for those people who have upgraded to either Scorpion or Miltek exhausts. What have you done with your original OEM Exhausts? EBay, keep them for some reason?
Also, do they only fit the RS3 of would they fit an A3/S3 or will the cars need altering first as I am wanting to sell mine and I have no garage space for mine.

Currently mine is listed in the RS3 sales section but I will be moving the advert into the General Sales section and linking it back to the RS3 section and I will possibly advertise on EBay too.
 
Surely you aren't going to tell your insurance company you have an illegal modification...?
 
I've kept mine and will refit the OEM system before selling the car, eventually. I declared the minor mod to my insurance company and it was not an issue. Audi haven't noticed/haven't mentioned it...
 
I've kept mine and will refit the OEM system before selling the car, eventually. I declared the minor mod to my insurance company and it was not an issue. Audi haven't noticed/haven't mentioned it...

Sorry I'm confused, you told DL that you have fitted a decat to your car and they said that's fine???

Legally speaking that is not fine lol!

Legally speaking the car is now not road worthy..
 
Since the car is fitted with 3 catalysts and the rear 2 are not measured for efficiency by the engine control unit insurance companies will cover them.
If the car was stopped for a road side check or presented for an emissions test the car would pass the mot criteria.
It's only come MOT time that the tester could notice the secondary cats are missing.
Probably only an issue when presenting your car to an Audi dealer who is knowledgeable in what cars should and shouldn't have the extra cats.
I wouldn't call it not road worthy.
 
I have always defatted my cars, I'm not being a goody goody or anything but there is no way an insurance company would accept that, surely. They have very low emissions for such high performance hot hatches because of new technology and the three cats, I do not believe for one minute that an insurance company would allow you to remove any of these.

My dad has an old st200 with two pre cats either side of the v6 on the manifolds and one central one on the actual exhaust system. He fitted new stainless 4,2,1 manifolds and therefore removed the two precats, the car went in for mot that year and passed. He then got a full stainless system and removed the final cat. Even though I think the car is road worthy and I'm sure you all would, removing any of the cats in the eyes of the law would surely see the car not fit for the road.

If you had an accident and wrote the car off I personally think the insurance company would **** you up the *** when they realise you have removed two of the cats, whether they are connected to the ecu or not...

I would personally get a full system and remove all three cats, I just can't see an insurance company giving this kind of mod the okay!?!

I hope that makes sense lol
 
I understand what you mean.
Although there's about 5 people I know of who've declared this mod with their insurance company and its been accepted as a mod?
An insurance company will insure a car with a sports stainless exhaust which all have these secondary cats removed.
I think I'm going to do this mid at some point on mine, I'll be declaring it with my insurance and making sure my documents list secondary cat bypass pipes.
 
Ah right, fair enough lol. Everydays a school day.

I bet they sound good with them out
 
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so jealous of you guys who have the rs3 btw!
 
Firstly, I'm not insured with DL anymore. I can't exactly remember the specifics but I discussed it with LV and they approved the change of pipes - I may or may not have gone into detail about the cat but I provided all the details they asked for and this doesn't involve total cat removal as there is at least one or two (?) more and I'm aware of some that have passed the MOT with the mod in place, although perhaps not at an Audi dealershit. I'm loving the improved sound that the mod has provided - not massively noticeable really unless you give it some in sport mode with the S button down, then it booms/shunts!
 
The secondary cats made only 0.01% difference to my emissions: a pre-MOT without secondary cats the CO was 0.02% while the actual MOT with secondary cats with was 0.01%

Stafford Audi (a with a different MOT tester to the one undertaking the pre-MOT) would not MOT the car without secondary cats - and I fully agree with the rules surrounding this issue. Post MOT, the secondary cat by-pass pipes are back on; I too love the noise.

As for the insurance; my secondary cat by-pass pipes are listed and were a no cost addition.

Just love the less-muted noise from BLUEY's 5-pot...
 
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I declared my Scorpion with DL, Cats were not altered and DL have not had issues. It has been fitted since December and they have renewed my insurance without any problems and I have also had an MOT without issues. I also have had my car serviced at an Audi Approved Independant so no more PITA problems with my local dealer like I used to get.
Although it would be nice to keep hold of the original exhaust to then swap back in another 2-3 years the problems I have are 1) transporting exhaust home as I have not got a car or boot big enough 2) my garage is not dry enough for storage 3) my independant will not be best pleased to look after it for 2-3 years 4) if/when I exchange the exhaust I will have the same issue with having an extra Scorpion Exhaust as I cannot guarantee I will buy another RS3, 5) As I don't have access to a van I cannot go to any car events/meets.
 
I dont know what your asking then, if you can't store it sell it. If you can store it, keep it!

As for your statement you declared the Scorpion but Cats were not altered, doesn't make sense. If you fitted a Scorpion system (Good choice by the way) then by definition you have altered the Cats as there will be less fitted than there was before you started?
 
If your original exhaust is still with Scorpion, why don't you ask them to chop it and weld 2 flanges on and supply you the bolts / gaskets thus making it a 2 piece system suitable for transporting in a car!