DE CAT or DP DE CAT

s3schofield

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Right im just starting modding my new s3 ive got a tip filter and dv , i wanna go stage2 im getting an intercooler , but will just a decat and cat back system be ok on standard DP or do you really need a bigger DP to support stage 2 revo?

thanks

chris
 
I would say downpipe is well mate they are restrictive well help turbo spool quicker iswell
 
Get a downpipe AND decat.

Standard downpipe on an A3 -

312043_10150463745910130_709735129_11090268_1318365028_n.jpg


And a 3" downpipe -

310606_10150463746655130_709735129_11090275_691793176_n.jpg


Makes a BIG difference and is as good an upgrade on an S3 as an A3.
 
Never as cool as you but flames would look sickkkkkkkkk blood :) flames alone have got to add 5bhp.
 
Never as cool as you but flames would look sickkkkkkkkk blood :) flames alone have got to add 5bhp.

Fact blud, flamez r wel sik.

On a serious note, downpipe and decat FTMFW. My car is 3" downpipe, but then the decat is a 3" which shrinks to 2.5" then down to 2.25" for the standard exhaust, I cut mine down to the 2.5" shrink and have a full 2.5" mild stainless from the downpipe back. It has made SUCH a difference, fair enough my car is stage 2 but with the standard downpipe it was down by 20/30BHP.
 
Do these engines require any back pressure? Were you not tempted to just run 3" all the way, in an ideal world I want speedboat idle noise with full on chatter, obviously avoiding any chavvy stigma. I'm not too fussed on speed anymore but a certain turbo noise is porn to my ears, I want to pick my kids up from school and all their mates say; WTF.

(not sure I should use porn and kids in the same post) sorry.
 
Do these engines require any back pressure? Were you not tempted to just run 3" all the way, in an ideal world I want speedboat idle noise with full on chatter, obviously avoiding any chavvy stigma. I'm not too fussed on speed anymore but a certain turbo noise is porn to my ears, I want to pick my kids up from school and all their mates say; WTF.

(not sure I should use porn and kids in the same post) sorry.

If thats what you're into I'll happily pick your kids up from school as a trial run for what their friends reaction will be like :thumbsup:

I'm not sure back pressure is really required on a 1.8t (Tuffty?), I don't think the manifolds on an A3 (unless you spend big money) particularly free flowing. There is a little difference on mine with a THS cast hi flow manifold over Prawns IDENTICAL car with a standard manifold, I should think with a hybrid on it would be a more noticeable difference though. Personally the best noise is an open turbo, a 5 pot Audi with an open turbo = TRUE car porn



I love the sound of my car, it is VERY low and pops and bangs SO loud as anybody who was at ADI will confirm! At the sound test I made it backfire on the way down from the 4.5K hold (because I'm a chav) and measured 140db! My exhaust was hand made by Longlife.
 
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Thank you, that's what I'm talking about although I'm very disappointed with whoever this was, absolutely no warm down before shut off, animals! Now finish the argument for me and tell me I can run my car (agu) without a dv, I beg you.
 
Thank you, that's what I'm talking about although I'm very disappointed with whoever this was, absolutely no warm down before shut off, animals! Now finish the argument for me and tell me I can run my car (agu) without a dv, I beg you.

You could do but it wouldn't like it, it'd cause boost spikes all over the place and throw its toys out the pram.

You've got to imagine having 15 to 18PSI wondering where the hell it's going to go after you've given it some beans and come off the throttle...
 
You can run agu with fully atoms dump :) , I want a one box system and dp Decat how do you get it to bang etc, my polo 1.8t was de cat and straight through but could never get bangs etc :-(
 
You have to have mad skills, I can make my car pop and bang REALLY loud anywhere.

I tend to give it some beans or clutch in and rev it to 4K then when it's dropped back down to 2/2500RPM just tap the throttle with my toes real quick. Failing that changing gear it licks em out quite well.

You can run an AGU with no DV/atmospheric, but it isn't worth it. Have you ever been in an atmospheric DV'd 1.8t? Laaaaaaaaag much!?
 
Thank you, that's what I'm talking about although I'm very disappointed with whoever this was, absolutely no warm down before shut off, animals! Now finish the argument for me and tell me I can run my car (agu) without a dv, I beg you.

DV is there to protect the turbo... you will destroy a little K03 without one and 1.8t's require recirculating valves not atmos ones as they cause running issues...

As for back pressure... excessive back pressure will cause egt's to rise and thats bad.... I ran a 3" straight through system on my S3 for a while with no problem at all... I only changed the back box due to noise...

<tuffty/>
 
Cool I'm gunna get the xs DP that's come out will this be ok on standard cat back system on stage 2 till I can raise funds for the rest?

Chris
 

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