S3 High-Flow sports cat

[Booth_S4]

seen this on ebay for the S3, http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&sspagename=ADME%3AL%3ARTQ%3AUK%3A1&viewitem=&item=300057599724&rd=1


sent the guy a question asking

"Hi there, the s3 has got a double cat in ie 2 side by side! how will this one your selling work in place of the standard one as the dont even look the same!

thanks"

the response i got was

"Hi . This down pipe and sports cat has been designed to do away with the restrictave standard down pipe and cats . It is a direct replacement for the standard one . Alot of chipping companys offer a stage 2 upgrade when these are fitted , so it an excellent bit of kit if your after the most you can get out of your S3 . Thanks John"

Is this guy right or should the high flow cats be like the miltek ones and have a double barrel!?

 

[james0808]

Im sure this guy used to work at awesome gti.Ask awesomesarah about him.

 

[Booth_S4]

cheers will do!

 

[s3bow]

Save your money mate. Did this on my S3 , 3" off the turbo to a 100 cell Rosi cat then on to a milltek. Makes absolutely no difference whatsoever. Just boomy at 3000-4000 rpm. Think of better ways to spend £600.

Chris.

 

[Booth_S4]

nice one for the heads up mate! i had heard this before but you have just made my mind up!

 

[mazzy]

Save your money mate. Did this on my S3 , 3" off the turbo to a 100 cell Rosi cat then on to a milltek. Makes absolutely no difference whatsoever. Just boomy at 3000-4000 rpm. Think of better ways to spend £600.

Chris.

I can comment on this, i've got a similar setup but no cat. Running a Stage II and makes a hell of a difference!!

These will be available Jan/Feb from MIJ Performance, will get prices sorted then. Also im getting my car dyno'd soon, will get some figures up.

Only worth it if u tweak your map up and run a Stage II, makes hell of a difference. Faster Spool up of Turbo, call me if you need details 01922 645 646.

Maz

 

[s3bow]

You must be the only one to get any more with a d/p. You must also have an early car with no second probe I take it ? Plenty on here have tried it before. No matter how we changed the map there was no difference. Faster spool up ? Certainly not enough to notice.
There's an old thread talking about this on the S3 forum. Conclusions were as I've said. I was gutted. Spent £480 on the d/p and cat and £440 for the milltek. Utter waste of money. And worse still I'd been told by some on here not to bother. Didn't listen. Had to find out for myself. The hard way.
I'll be honest with you about my experiences, and we spent many a sunday altering the map trying to improve. I won't waffle on about some tuners and their claims because its already been said.
Just because you spent the best part of a grand there's no guarantee of extra performance. Truth is, the d/p , standard cats and system are not restrictive for a 1.8 engine even with 1.5 bar. Its a myth. As I found. It doesn't flow the sufficient quantity to be restrictive.
Tuners will say differently though.

Chris.

 

[mazzy]

Well, my car is a 2001 with both lambda probes. All i can say is i had the d/p fitted before my stage II map and i didnt really notice much difference, but since the map & 4bar fuel regulator & other bits etc. A great difference!

The setup has to be right, a milltek cat-back is 2.75" bore, way to big... the reason for that is tooling. 1 bore size for all, whereas i have a 2.5" from downpipe then reduced bore in 2.25" and finally 2" bore in the backbox. I tried 2.5" all the way and 2.5" not as good, not enough torque as my final reduced bore setup.

Those that know my car, and have been in it know the difference.

 

[s3bow]

Mate, I had the wrong end of the stick. Thought you meant the gains you felt were big were due to the d/p swap alone.
Did you have to go down to 2.25 to get past the bulkhead and prop ? It was f*****g tight in there. I know what you are saying about Milltek using 2.75 too. 1 set of dies for the bend tooling yeah ? What you done about the second probe ? I had a check light forever on with the Rosi cat. I did read somewhere that there was a way of programming out the second probe and a "fool" box as the jap boys use.
Nice to see someone tuning the exhaust to produce what they want too. Good on you. What have you gone for ? Torque instead of big horsepower ?

Chris.

 

[Ess_Three]

Save your money mate. Did this on my S3 , 3" off the turbo to a 100 cell Rosi cat then on to a milltek. Makes absolutely no difference whatsoever. Just boomy at 3000-4000 rpm. Think of better ways to spend £600.

Chris.

Well done Chris...
You found the same as me...not worth the cash.

I never saw anything close to the gains Milltek claimed.
In fact...I saw ****** all.
A really good way to spend £600.

 

[Ess_Three]

You must be the only one to get any more with a d/p. You must also have an early car with no second probe I take it ? Plenty on here have tried it before. No matter how we changed the map there was no difference. Faster spool up ? Certainly not enough to notice.
There's an old thread talking about this on the S3 forum. Conclusions were as I've said. I was gutted. Spent £480 on the d/p and cat and £440 for the milltek. Utter waste of money. And worse still I'd been told by some on here not to bother. Didn't listen. Had to find out for myself. The hard way.
I'll be honest with you about my experiences, and we spent many a sunday altering the map trying to improve. I won't waffle on about some tuners and their claims because its already been said.
Just because you spent the best part of a grand there's no guarantee of extra performance. Truth is, the d/p , standard cats and system are not restrictive for a 1.8 engine even with 1.5 bar. Its a myth. As I found. It doesn't flow the sufficient quantity to be restrictive.
Tuners will say differently though.

Chris.

Bravo! :thumbsup:

Thank the lord for people who can see (or not) genuine gains without the placebo affect of having their wallet lightened.

Well done...there is too much of this 'big gains' ******** spoken on here.

 

[Ess_Three]

I can comment on this, i've got a similar setup but no cat. Running a Stage II and makes a hell of a difference!!

These will be available Jan/Feb from MIJ Performance, will get prices sorted then. Also im getting my car dyno'd soon, will get some figures up.

Only worth it if u tweak your map up and run a Stage II, makes hell of a difference. Faster Spool up of Turbo, call me if you need details 01922 645 646.

Maz

Since everything you fit (and also sell...*shock*) seems to make a HUGE difference...how about some before and after dyno plots from an independant dyno?

Because without that, you're just blowing smoke out of your ***...and possibly ripping people off.
And that really hacks me off.

But I'd love to be proved wrong.

 

[Booth_S4]

^^^^ Does seem funny how a guy from a pefrormance shop says it makes the world of difference and some one whos neutral ie doesnt have a performance shop and a living to make says it makes no difference!

 

[Ess_Three]

...and the owners who have spent (wasted?) their own hard earned cash can provide dyno plots to back up their observations...from many and varied independany dynos.

Maybe I'm sceptical...but I'm sick of people being taken for a ride on heresay and false dyno plots.

Let's see the proof...I really would love to be proven wrong.

 

[mazzy]

^^^^ Does seem funny how a guy from a pefrormance shop says it makes the world of difference and some one whos neutral ie doesnt have a performance shop and a living to make says it makes no difference!

What shop??

I work at MIJ, dont mean im bulls***ting. I've tested other exhaust setup's including the alterations i made on my REVO map & yes it has made a difference, what i did say earlier is that without a MAP it made little difference.

Like i say, come and demo my car if you dont believe!!

 

[mazzy]

Since everything you fit (and also sell...*shock*) seems to make a HUGE difference...how about some before and after dyno plots from an independant dyno?

Because without that, you're just blowing smoke out of your ***...and possibly ripping people off.
And that really hacks me off.

But I'd love to be proved wrong.

What are you on matey???
Either you dont read the posts properly or you cant read very well. For a start have you tried & tested everything i have done on my S3???

If not then you can keep your "I know it all comments to yourself"... Yes you do give very good advice on alot of stuff and yes i appreciate your advice. Infact i do take it at times. I dont rip people off, i work at MIJ. Don't mean i force people to buy parts, i recommend YES. Thats it!

I dont think anybody is running a setup like mine, as i've gone the more torque route which is why it makes a more noticable difference.

Just have not had the time to get a dyno plot. I better get up and get that sorted as this is taking the ****!!!

Sorry no hard feelings!!

Maz

 

[mazzy]

Mate, I had the wrong end of the stick. Thought you meant the gains you felt were big were due to the d/p swap alone.
Did you have to go down to 2.25 to get past the bulkhead and prop ? It was f*****g tight in there. I know what you are saying about Milltek using 2.75 too. 1 set of dies for the bend tooling yeah ? What you done about the second probe ? I had a check light forever on with the Rosi cat. I did read somewhere that there was a way of programming out the second probe and a "fool" box as the jap boys use.
Nice to see someone tuning the exhaust to produce what they want too. Good on you. What have you gone for ? Torque instead of big horsepower ?

Chris.

Hey Chris,

The downpipe is 3" all the way, then under the car is a 2.5" bore upto the middlebox then it reduces to a 2.25" bore and follows into a 2" backbox and then tailpipe.

All probes are in place and no engine light.

Maz

 

[confusionhunter]

Like Mazzy says... he'll get some dyno graphs up soon..... lets not start a slagging match....

 

[Ess_Three]

What are you on matey???

Only on the lookout for wide boys out to rip people off with outlandish claims - lets face it, the 'my S3 is as fast as an RS6' wasn't a good start, now was it?

You give us the proof...and we'll make our own mind up.

You are 5 years too late to be a pioneer...so I'd sceptical that you have found a special mod / secret to eternal life that hasn't already been found / tried.
So...give us the proof...

Either you dont read the posts properly or you cant read very well. For a start have you tried & tested everything i have done on my S3???

I suggest I read a lot better than you!

So...if you have all these independant dyno plots showing boost, ambient temperature, fuelling, power and torque, to back your claims up...then post them.

If not then you can keep your "I know it all comments to yourself"...

Ooh...cage rattled is it?
Give your head a shake.

I don't know it all, but I can spot a bullshitter at 20 paces.
If the cap fits...

I dont think anybody is running a setup like mine, as i've gone the more torque route which is why it makes a more noticable difference.

Really?
Mine was...
1.89 bar peak boost...332 lb-ft.
I know what torque is, and at what revs/boost...so once again...lets see some dyno plots.

I have never come accross a higher torque K04 S3 than my old one, so forgive me if I hear stories about gains you got, cars you've beaten/kept up with...what I know damn well mine wouldn't have.

I better get up and get that sorted as this is taking the ****!!!

Oh, this isn't taking the ****...
I can start that is you wish?

Let's see before and after dyno plots...all parameters shown..
I have 30+ independant dyno plots for mine...showing every mod, before and after...so I CAN say what worked and what didn't.

Sorry no hard feelings!!
Maz

No hard feelings here Maz...
I'm just keen to see the real gains...I hope you found gains I couldn't.
But having been ripped off for many years...I'm sceptical until I've had things proved.
No hard feelings here...just that's the way I am.

 

[mazzy]

Its not about being ripped off. I have paid also for all my mods & they have made a difference, the spool on it is like there is no lag at all. Why dnnt we meet up???

Besides you saying that even with the power you were running the S3 dont stand a chance against a Scooby etc. its bogus because ok an S3 wont launch off quicker you will maintain if not beat the gap the scooby has on you. So it boils down to getting it right in the S3 so they cant gain on you. 2 cars can never launch the same time as drivers differ so 1 will always launch 1st (quickest reactor) so why not that 1 be ME!!!!

With the boost & setup you were running you should've gained and maintained. Power to Weight!!!!!

Oh and whats with the 996 Turbo front end? Wannabe!!

 

[Ess_Three]

Oh and whats with the 996 Turbo front end? Wannabe!!

Ignorant peasant!
It's a C4S.
As it came from the dealer...

C4S's have a turbo body and front end. If I'd wanted a turbo, I'd have bought one. I could have got one for considerably less than the C4S cost me.
I didn't want one...they aren't as nice to drive.

Faster...but no panache.

So get things right before you make smart comments...or you end up looking a tit.

 

[Ess_Three]

Its not about being ripped off. I have paid also for all my mods & they have made a difference, the spool on it is like there is no lag at all. Why dnnt we meet up???

Don't take things personally, but one persons "hell of a difference" or "big difference" is easily influenced by the amount of cash that's been levered out of their wallet!
I tried most of the 'tweaks' available for the S3...and found that despite the placebo effect telling me things should be better...most did nothing.

To me, a gain is a repeatable, dyno proven gain...anything less if subjective...and frankly, worthless.
Independany dyno tested (ie, not the maker of the part...it's too easy to make dynos show what you want them to...I'm experienced enough on dynos to know the tweaks and tricks) with before and after runs on the same day, same fuel, same operator, same map etc.

As I said...I'd love to be proved wrong and see that you've tried something that's given a decent gain...but my experience is that most things have been tried by now, and there is no secret tweak.

Besides you saying that even with the power you were running the S3 dont stand a chance against a Scooby etc. its bogus because ok an S3 wont launch off quicker you will maintain if not beat the gap the scooby has on you.

I'm not saying anything of the sort.

Mine was quicker off the line than many Subarus...but since the S3 is low geared, when you change gear, they make up ground.
0-60 the Subaru may win because it hits 60 in 2nd (the S3 doesn't) but 0-80 the S3 can take it.
This is no news to me...

The Jap import STIs (Type-Rs) are difficult as they have a closer ratio 'box...and they just keep pulling...

With the boost & setup you were running you should've gained and maintained. Power to Weight!!!!!

Hmm...not sure I follow:
Even at 275+ BHP and 332 lb-ft in an S3, you are heavier and often making less power than the Surarus (for example). The Subaru also has a longer rev range...

Mine was quick (Not RS6 quick though! ) so with WRXs/STIs/Evos...some you win, some you loose.
Pick the right road...and you'd come out in front.
The wrong road...you loose.

 

[mazzy]

Hmm...not sure I follow:
Even at 275+ BHP and 332 lb-ft in an S3, you are heavier and often making less power than the Surarus (for example). The Subaru also has a longer rev range...

Mine was quick (Not RS6 quick though! ) so with WRXs/STIs/Evos...some you win, some you loose.
Pick the right road...and you'd come out in front.
The wrong road...you loose.

Exactly so what is so hard to believe in the old thread?

Some you win, some you loose. You've just got to get it right!

 

[Ess_Three]

Because an RS6 has 420BHP minimum, only weighs a few hundered Kgs more and has enough torque to pull the sides off a house.

In an S3, you loose. Every time.

...except on handling.

 

[Ballcrusher]

do wat i did if ya got a eatly one

£105 from rsr in croydn

 

[mazzy]

do wat i did if ya got a eatly one

£105 from rsr in croydn

You can do this on later 1's too. Aslong as the probes are put back in properly.

 

[Ess_Three]

How do you avoid the engine check light coming on, and the "Catalyst Efficiency Below Threshhold" fault being logged, on the later cars?

Mine was a 210, and it used to come up when running Milltek 100 cell cats that had done 10,000 miles.

Give them (Milltek) their due, they replaced the cats with 200 cell versions to avoid the check light.
But I can't see how you can avoid the engine check light if you don't run cats.

So how do you do it on later cars?

 

[Booth_S4]

and what gains are to be had when this is done? surely not alot if any!

 

[Ess_Three]

I found no real gains when going to 100 cell cats (you can see straight through them!)
No change when the car went to 200 cell cats either...

Other cars have tested de-cat pipes and also got no gain and engine check lights on.

Personally, having been stopped twice for a routine roadside check, I wouldn't remove the cats anyway...
1. I don't want to get caught and fined.
2. I don't believe in it...if you can't tune keeping emissions compliancy, then you don't know what you are doing...so don't at all.
But these are my views...


With regard to high flow cats or de-cat pipes...I've never seen one make a 'good' gain.
By good, I mean a quantifiable, dyno proven, repeatable gain in power or torque.
On my S3 the dyno showen no more power...but I did get a slight gain in torque (parhaps 5-10 lb-ft) but this wasn't repeatable enough to quantify with certainty....the rolling road accuracy is approx 5% anyway (5% of 300 lb-ft = 15 lb-ft...so you get my point!)

It appears that the boost control circuits on the S3 are quite slow, and it's possible to get slightly more boost at peak torque that with standard cats...presumably the reduction in exhaust restriction allows the turbo to mildly 'overboost' before the ECU regains control.

That being said...
100 cell, 200 cell or de-cat have not given ANY ADDITIONAL PEAK POWER.
This is on 4 or 5 cars I trust...with people I believe, using a 'control' dyno.

Perhaps a gain in torque...the 'butt dyno' would suggest it feels more aggressive to drive...but since I couldn't prove it...I suggest it was the placebo effect of having my wallet lightened to the tune of £700.


People are welcome to read into that what they like...

 

[Booth_S4]

thanks for all your help mate!

 

[Ballcrusher]

my car only had i lamda so it was easy dont no obout later cars

 

[s3bow]

I ended up clearing the cat fault code every week. So when Mazzy says it can be done, yes it can but you will get a check light and a fault code.

Chris.

 

[Ess_Three]

Which doesn't really seem worth it to me...

No real gain, and a check light for your trouble.