S3 8P BCS Downpipe fitting

Muzza80

Muzza80

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Alright folks, just wondering if anyone fitted their own downpipe to their S3 8P?

I'm pretty mechanically minded, have been successful with most thing's I've tackled in the past.

I removed my intake this evening to investigate access to the turbo/downpipe flange bolts, top lambda sensor and to give them all a good blast of penetrating oil prior to tackling this later on in the week or the weekend.

After getting the intake off and having a good look down the back of the engine access from the top is a nightmare as you cannot remove the stock heatshield, one of the flange nuts is completely hidden in behind the exhaust/turbo manifold and all in all it looks like it will be a nightmare tbh!

Prop disconnection I'm not worried about, removing the actual exhaust sections again don't look like it will be a problem, I've had problems in the past with lambda sensors but hopefully I'll get them out as have a proper lambda wrench.

Can anyone give me reassurance that the upper rear flange nut is more accessable from underneath??

Any other tips?

Cheers!
 
I got to all of mine from the top. 3 of the with a ratchet and socket and the lowest one (closest to the floor) with a spanner. You need the move the prop quite a bit to fit the standard pre cat out the small gap !
 
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I done mine on a jack and stands at home.
Once the engine covers removed I removed the top lambda and the 3 bolts you can access, the one nearest the heat shield I used a long extension and worked the ratchet from above the gearbox. (All very easy)
On the underside I had to cut the bolts on my exhaust clamp/sleeve as they were seized solid.
Undone the lambda and then disconnected the 3 splined bolts from the prop which made access to the last front pipe bolt much easier.

Here's where the hard bit comes, trying to remove it through the gap.
I ended up dropping the prop support and u doing the 2 lower gearbox mounting bolts and pushed the engine forward with my foot and wangled the downpipe out.
I vowed it's never going back on as it was a pain to get out.
As your new one will be in 2 pieces it slips in much easier.
I'd allow 3 hours on the floor as removing it through the gap takes a little time.
Good luck and yes it's totally worth it when done.
 
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Keeping an eye on this one going to be trying it in July with the BCS down pipe and sports CAT. Make sure you take some pics for a helpful guide.
 
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Can you tell me where you get these from as tried searching & cant seem to find retailer?
 
I fitted a milltek downpipe and sports cat to mine last week currently on a stage 1 map and does go better. Pulls better at lower revs but as said other supporting mods will unleash more potential
 
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mechanic69 said:
You'll need the CAI for Stage 2 and HPFP for 2+ to get full potential.
Click to expand...

Thanks. Got the CAI, BCS downpipe and HPFP next - along with budget for the clutch!

That's £1.4 / 1.5k in anybody's money...


So, in language I can associate with...

Going from stock to stg1 (shark) - pretty impressed, gotta say.


Then from stg1 to stage 3 shark (2+, everybody else) whassit like???



Tease me please. :yum:

P

Sorry, just realised I've totally hi-jacked this thread. Sorry Muzza.
 
Last edited:
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Marshy said:
I done mine on a jack and stands at home.
Once the engine covers removed I removed the top lambda and the 3 bolts you can access, the one nearest the heat shield I used a long extension and worked the ratchet from above the gearbox. (All very easy)
On the underside I had to cut the bolts on my exhaust clamp/sleeve as they were seized solid.
Undone the lambda and then disconnected the 3 splined bolts from the prop which made access to the last front pipe bolt much easier.

Here's where the hard bit comes, trying to remove it through the gap.
I ended up dropping the prop support and u doing the 2 lower gearbox mounting bolts and pushed the engine forward with my foot and wangled the downpipe out.
I vowed it's never going back on as it was a pain to get out.
As your new one will be in 2 pieces it slips in much easier.
I'd allow 3 hours on the floor as removing it through the gap takes a little time.
Good luck and yes it's totally worth it when done.
Click to expand...

Can you explain the prop part more please, I tried what you did but I didn't touch the propshaft. When you mean propshaft support do you mean you removed the 3 x 10mm 12 spine bolts at the rubber doughnut?
 
I think he means the centre support, half way down the propshaft if you release it it will give you more room
 
Yeah as Granta says I removed the 2 13mm bolts that supports the prop shaft through the heat shield which allowed more movement.
Probably not required on a lift but I certainly needed it undone on the floor.
 
Just speaking to Nige at BCS there for a couple of other tips and to get a couple of new band clamps sent up.

He's warned me that the downpipe makes it sound pretty raspy without the rest of the system and just to be aware of that.

Can anyone confirm...., does it sound horrible with just the downpipe mated up to the standard back system lol?
 
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This is the setup I have at the moment as I removed and sold my Milltek.
When its cold it's really raspy and sounds like there's a leak in the system (not bad but I'm fussy)
Once warm it sounds nice almost like a powervalve setup once the extra flap opens.

My next step is to speak with Nige and see if he will mate a catback up to my cobra downpipe then I'll have perfection.

It'll be a few months once I get holidays etc out of the way
 
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Muzza80 said:
Just speaking to Nige at BCS there for a couple of other tips and to get a couple of new band clamps sent up.

He's warned me that the downpipe makes it sound pretty raspy without the rest of the system and just to be aware of that.

Can anyone confirm...., does it sound horrible with just the downpipe mated up to the standard back system lol?
Click to expand...

Isn't that to just make you buy the whole system not half of it????
 
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RedDejavu said:
Nice one buddy hope you enjoying it:)
Click to expand...

Going well mate thanks. I have had to space the 2nd O2 sensor as the light came on after 2 days and will get it mapped out when I go stage 2+ but really enjoying it
 
Marshy said:
Yeah as Granta says I removed the 2 13mm bolts that supports the prop shaft through the heat shield which allowed more movement.
Probably not required on a lift but I certainly needed it undone on the floor.
Click to expand...

Hats off to you sir if you didn't need to remove the propshaft from the gearbox. I tried with removing the centre support but in the end just removed the propshaft. Wish I had done it sooner as it'd would have taken me less time in the end.

Had to angle grind a bit off the BCS sports cat to get it to mate with my miltek cat back system. Ready to go stage 2+/3 once the clutch has been replaced!
 
I dropped the 3 bolts on to the transfer box first and still couldn't get it out that's why I dropped the centre support.
What clutch you going for?
 
Probably the Helix clutch with SMF kit. The friction plate has springs so it shouldn't I hope chatter as much. Can get it all for £811 so not too bad...
 
So just to clarify....

-Remove the intake
-Undo the top lambda sensor
-Undo the 3 accessible turbo/downpipe flange nuts from above in the engine bay
-Undo 2nd lambda from underneath
-Undo exhaust centre section from OE downpipe and rear section and remove
-Undo 3 front propshaft bolts
-Undo 2 prop shaft centre brace bolts
-Slide propshaft over to the drivers side of the car
-Undo remaining downpipe/turbo flange nut
-Wrestle the standard downpipe out of the space left after moving the prop to the side
-Re-assemble in reverse order?


And I can defo do all that with the rear of the car on ramps and the front up on axle stands, specifically getting the old downpipe out with the limited space under the car?

How do I support the propshaft when it's undone from the front and centre?

Thanks!
 
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that's its although my system fell out once I removed the three propshaft bolts! The propshaft is fine hanging tbh well I left mine and it's still fine :p
 
Muzza80 said:
So just to clarify....

-Remove the intake
-Undo the top lambda sensor
-Undo the 3 accessible turbo/downpipe flange nuts from above in the engine bay
-Undo 2nd lambda from underneath
-Undo exhaust centre section from OE downpipe and rear section and remove
-Undo 3 front propshaft bolts
-Undo 2 prop shaft centre brace bolts
-Slide propshaft over to the drivers side of the car
-Undo remaining downpipe/turbo flange nut
-Wrestle the standard downpipe out of the space left after moving the prop to the side
-Re-assemble in reverse order?


And I can defo do all that with the rear of the car on ramps and the front up on axle stands, specifically getting the old downpipe out with the limited space under the car?

How do I support the propshaft when it's undone from the front and centre?

Thanks!
Click to expand...

can see a pic heavy guide coming on
 
I only jacked my rhf wheel up and with the prop moved over I still needed to undo the lower gearbox mount bolts to allow the engine to move forward.
Apart from that the rests fine.
 
Hi mate, I've just bought a milltek sports cat down pipe for my s3 8p. I still have the standard exhaust on the car , which I belive is 2.5 inch diameter. But the milltek is 3 inch diameter. So did you have to fit a adaptor for the sports cat to fit?

Regards Sam
 
Wow over 5 years gone by.
Yes I needed a reducer which came with the downpipe.
Can’t remember the exact size though.
 
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