Backbox Options - Post Your Pics Please...

[Ryan_W]

Guys,

Looking to get a full 3" custom built exhaust for my S3 and I'm struggling to decide on which tailpipes to have...

This is where I need your help in 'showing me yours' before I take the plunge.

I think I want something similar to OEM but a tad bigger...

Here's mine as it currently stands with its standard exhaust.

Cheers in advance...

 

[Ryan_W]

I'm thinking something like this (obviously only one side):

or like this:

 

[superkarl]

the above tailpipes are the milltek slash cut. i have these. they look good

 

[Ryan_W]

Are they not slightly larger than the S3 8L tips? Certainly look it?....

 

[Prawn]

I thinki you're on the right lines Ryan, twin 3'' pipes, slash cut at the ends with no fancy rolls or flares, looks mean and purposeful to me.

Where are you going for a full 3'' system? Most places I've approached won't do bigger than 2.5''!

 

[Benjiman46]

Powerflow RAiT tailpipe, Relentless downpipe and decat with 2.5" custom system. Sound shweeeeet!..

 

[Paradox1]

Video of how it sounds or it never happened

 

[Ryan_W]

I thinki you're on the right lines Ryan, twin 3'' pipes, slash cut at the ends with no fancy rolls or flares, looks mean and purposeful to me.

Where are you going for a full 3'' system? Most places I've approached won't do bigger than 2.5''!

Exactly mate, I don't want any bling, just agressive looking.

Hayward & Scott shall be making my exhaust, one of the best fabricators in the UK. It goes without saying that it's all done properly ie: mandrel bends and welding that should in an art gallery!

 

[superkarl]

Hahaha, ask stacey about hayward and scott.I originally approached a powerflow dealer who said he would do 3 inch, only thing when places do 3 inch they nearly always buy pre bent pipes rather than bending their own, most places can't, hence why most places say no. My milltek slash cut tips fill the bumper recess very well. Think I put pics in my thread

 

[s3 Hoggy]

I have the miltek slash cut havnt really got a great pic but you can sort of see it

 

[StaceyS3]

Will post some links up shortly but please avoid Hayward and Scott like the plague!
Needless to say they've had mine back 4 times and have agreed to give me a full refund when I return it, and some of the comments I've had from them are a joke like "bolts will naturally fall out of downpipes" (5 out of 7 bolts to fall out in 250 miles after they fitted the second set as drove straight to Gloucester for mapping) and "what do you expect it's normal for a 3 inch downpipe to rub on a car like this" as was apparently asking the impossible and wouldn't have it when I tried to show them that could buy 3" downpipes off of the shelf for S3's and other transverse 1.8t's!
The final straw was the fact it was wearing through my power steering pipe which could have caused a huge fire had it broken through for them just to throw back a stupid comment like above, please do yourself a favour and don't go there as they may do some lovely work (lovely job on a friends custom manifold and full system) but obviously are no good with tighter installs and some of their practices leave a lot to be desired

 

[Sam_]

Exactly mate, I don't want any bling, just agressive looking.

Hayward & Scott shall be making my exhaust, one of the best fabricators in the UK.

Apart from their S3 downpipes. Why not just go Milltek? This is their "special tips":

 

[coatesy]

this is my milltek on my a3.

 

[Prawn]

Apart from their S3 downpipes. Why not just go Milltek? This is their "special tips":

Not 3'' is it.....

 

[Jason.s]

Hayward are just hit and miss i think. As said before they did a full system with interchangable sportscat/decat pipes on an E36 track car with E46 M3 engine upfront for a garage i use and they did a good job. Quality wise is really good and that has he type of tips being shown in these pics above. It did cost over £2k though im pretty sure.

 

[superkarl]

I originally asked the powerflow dealer for 2.75 inch system, which they couldn't do, so agreed on 3 inch, but, I'm glad I never got 3 inch due to firstly the ground clearance, the 2.75 milltek is low, secondly its a little extra noise, and thirdly, there is no real need for 3 inch unless you are going crazy on the car.

 

[Jpd89]

Can anyone explain the differences between the jet tips and the special tips?! Trying to order my milltek cat back now but not sure which one to go with! Sorry for the hijack but it's a similar request so pointless starting my own thread!

 

[Ryan_W]

The jet tips are rounded as suck, the tail pipe is thicker. The 'special' tips are a slash cut, thinner walls and look much better IMHO...

I 'may' now go for the Relentless V3 mani and DP and mate it to a Milly. Ideally I still want 3" but after Stacey's experience, it's a little off putting!

They've done work on my old track cars and it was excellent, but this was a few years ago.... Hmmmmm.....

 

[AVLO]

is that your car benjiman? i think slash cut looks more aggressive but like things looking oem! cant decide what to do on my s3? desicions decisions

 

[Sam_]

Not 3'' is it.....

Nope - 2.75"

Ryan: Why the 3"? Going GT30/35?

 

[Benjiman46]

Video of how it sounds or it never happened

What?.. Me? lol

 

[coatesy]

What?.. Me? lol

at a guess its you. just because you said your zorst sounds sweet. im hooked now, video or it sounds gash!

 

[Benjiman46]

is that your car benjiman? i think slash cut looks more aggressive but like things looking oem! cant decide what to do on my s3? desicions decisions

And yeah it is mate

As mentioned above, 3" is not necessary unless you're going over 400bhp, 2.5" is adequate for up to about 350-380bhp.

 

[AVLO]

i got my turbo back exhaust done from brett up at top gear as i live local to them and i like his work very good quality work, i am looking into getting a back box side ways on same as yours on my new s3. how does it sound?

a video clip on start up wouldnt go a miss

 

[superkarl]

any excuse to share mine ...

[ytv]e2aah3-zBFk[/ytv]

 

[Gops]

i loved your car hoggy!! I fell in love when I saw iT at AITP!!

I have the miltek slash cut havnt really got a great pic but you can sort of see it

 

[s3 Hoggy]

Cheers bud!

 

[Prawn]

it's all about flow though isn't it lads?

There are cars running 400bhp with 2'' intercooler pipes. they work, but who knows how much it's restricting?

''standard manifolds flow fine'' don't they? Welly made 411bhp on a standard manifold, so it OBVIOUSLY wasn't a problem was it? until he fitted a high flow and cracked 445bhp.....

I'm all for experimenting, and I reckon there is potential merit to a 3'' exhaust system when going above 300bhp.

My hybrid AGU has more 'high flow' products than just about any other setup out there, and makes more power at 15psi then most hybrids make at 20psi.

I'm not saying it'll be night and day, but I reckon by giving the engine every possible chance you're most likely to get the best results.

I'm swapping out my 2.5'' system for a 3'' very soon

 

[superkarl]

Definately a good move for you prawn

I think the design of exhausts and backboxes is just as essential as size. Fluid dynamics is one complex subject I dare not read too much into, but its always good to get the biggest you can anyway, to be future proof. Everyone who has gone for a bigger system has felt the difference some how, I bet yours will be night and day prawn, despite it being quite a high flow system anyway.

I need to get my car to an exhaust place to have the 2.5 decat-oem bit removed, it will probably make sod all difference, but its on my mind.

 

[Ryan_W]

I plan on upping power in the near future, be it maxing out a k04 or going BT.

3" is future proof so worthwhile in my eyes.

 

[Prawn]

3" is future proof so worthwhile in my eyes.

This

 

[Benjiman46]

at a guess its you. just because you said your zorst sounds sweet. im hooked now, video or it sounds gash!

Haha ok

Here you go then

Standard map, 3" Down-pipe and de-cat with 2.5" powerflow de-cat-back system with 2 silencer boxes...

 

[Dani_B19]

As prawn said, ive had a full and i mean full 3" exhaust all the way through, even to the point were they cut the xs power decat and welded a flange on were it goes from 3" to whatever it is 2.75 etc and i made them keep it 3" even around the rear diff even though it means the exhaust sits slightly low on the back before it meets the box, i know that i never have to worry about any restrictions afterthe turbo now, plus its got a 25 year guarantee .

 

[colicabcadam]

3 inch also helps keep down the turbo temps from what i have been told.......... true ?

 

[Dani_B19]

I would guess so mate, if the turbo can get rid of the gases quicker then theres less backed up gases so should mean less heat, or thats how id see it lol.

 

[colicabcadam]

these are what you call downpipes.....

 

[Sam_]

This

Same as 6 pots then

 

[<tuffty/>]

3 inch also helps keep down the turbo temps from what i have been told.......... true ?

Yes, but its not just because its a 3"... I ran a std exhaust system for a very short time after I did the BT conversion on my car... EGTs were mental... I even had an EGT over temp fault code (1110 deg!!) and that was mostly due to the OEM back box being restrictive...

Granted I bunged a 3" system on afterwards and EGTs were sensible again but any decent free flowing system thats suited to the power output will so...

There are not many people doing 3" systems as you arguably need to be pushing a fair amount of power for it to be realistically beneficial and they are trickier to fit as that extra 1/2" (fnarr) can make quite a difference when trying to get it over axles etc...

For most peeps a 3" DP to a 2.5" (std S3 size) or the Milltek 2.75" is more than enough... 3" systems can sound raspy when cold but raucous when on it...

...and what I now have is...

<tuffty/>

 

[StaceyS3]

Do you think the milltek cat back will become a restriction on mine when running near full potential with the gtx as potentially could be chasing 500's?

 

[Prawn]

I have absolutely no genuine knowledge on your question Stacey, but in the interests of seeing more shiney parts in your build thread, I'm going to say Yes. it will be a restriction. get 3''