Is this Normal/Has this been changed?
10 January 2013, 07:11 PM
#1
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Is this Normal/Has this been changed?
Hi all, I was trying to understand a receipt I've got in my "car folder" which describes a job which the previous owner had carried out. I eventually found a post from this very forum which described the work as follows:
The car is a 2005 Blobeye STi with PPP fitted. I took the following photograph which illustrates the section of exhaust which I'm unsure about:
From what I can gather from looking at my car, the centre section through to backbox is 2.5" and the pictured part shows the exhaust funneling out into 3" for the section leading towards the downpipe.
What exactly has been done to my exhaust, and how should it be normally? If I was to buy a 3" catback system for example - am I going to be able to bolt on to my existing setup, or will my downpipe need changing too?
The car went in today for a de-cat,before it goes in on Monday
to get mapped. The garage who was doing the work for me
phoned me up and said that the car has a sports cat on ?? wich
was 5" in diameter and believed that the 3" de-cat could restrict
it more if he was to change it.I went down to look.We decided to
leave the sport cat,follow the pipe down unltill the diameter got to
3" cut it off there and started the 3" system from there.The guy said
It was a little more work,but was worth while doing and i would'nt need
to pay for the de-cat.He thinks it was the better option as it would
still get through the MOT as well. What are your thoughts.
Have i done the right thing ? will it be as good as a 3" de-cat.
Would i have had betters gains when mapped,with a de-cat.Or
do you think this sports cat will be OK ??.
to get mapped. The garage who was doing the work for me
phoned me up and said that the car has a sports cat on ?? wich
was 5" in diameter and believed that the 3" de-cat could restrict
it more if he was to change it.I went down to look.We decided to
leave the sport cat,follow the pipe down unltill the diameter got to
3" cut it off there and started the 3" system from there.The guy said
It was a little more work,but was worth while doing and i would'nt need
to pay for the de-cat.He thinks it was the better option as it would
still get through the MOT as well. What are your thoughts.
Have i done the right thing ? will it be as good as a 3" de-cat.
Would i have had betters gains when mapped,with a de-cat.Or
do you think this sports cat will be OK ??.
From what I can gather from looking at my car, the centre section through to backbox is 2.5" and the pictured part shows the exhaust funneling out into 3" for the section leading towards the downpipe.
What exactly has been done to my exhaust, and how should it be normally? If I was to buy a 3" catback system for example - am I going to be able to bolt on to my existing setup, or will my downpipe need changing too?
10 January 2013, 07:23 PM
#2
Hi Fonzey, are you still trouble shooting the problem(s)?
Looks to me that they've cut downpipe and welded flange to it and bodged it together or something, but can't be sure. Is it blowing at all in that area?
Best bet would be is to save up and buy a whole system, best to do it right once. For your power gain unless going over 400hp, I wouldn't go for a 3", stick to a 2.5 or 2.75 decatted.
Looks to me that they've cut downpipe and welded flange to it and bodged it together or something, but can't be sure. Is it blowing at all in that area?
Best bet would be is to save up and buy a whole system, best to do it right once. For your power gain unless going over 400hp, I wouldn't go for a 3", stick to a 2.5 or 2.75 decatted.
10 January 2013, 07:25 PM
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Hey Busta, yeah I'm still experiencing my "whistle" but I'm slowly beginning to wonder it it's just the normal soundtrack of my car - we seem to have ruled out all the possibilities.
I don't believe the exhaust is blowing in this area, it just intrigued me when I found the receipts for this work and found the quoted post from the previous owner. I'm not really sure why they would do this?
I don't believe the exhaust is blowing in this area, it just intrigued me when I found the receipts for this work and found the quoted post from the previous owner. I'm not really sure why they would do this?
10 January 2013, 07:31 PM
#4
Hm, probably to save pennies, but saying that it probably does the job it wants to do, but looks a bit bent and untidy IMO.
You still up for sat? Maybe I could have a listen for you and give you my opinion wether its Scooby noise or not. Has it got an induction kit on!
You still up for sat? Maybe I could have a listen for you and give you my opinion wether its Scooby noise or not. Has it got an induction kit on!
10 January 2013, 07:35 PM
#5
Hi Fonzey, are you still trouble shooting the problem(s)?
Looks to me that they've cut downpipe and welded flange to it and bodged it together or something, but can't be sure. Is it blowing at all in that area?
Best bet would be is to save up and buy a whole system, best to do it right once. For your power gain unless going over 400hp, I wouldn't go for a 3", stick to a 2.5 or 2.75 decatted.
Looks to me that they've cut downpipe and welded flange to it and bodged it together or something, but can't be sure. Is it blowing at all in that area?
Best bet would be is to save up and buy a whole system, best to do it right once. For your power gain unless going over 400hp, I wouldn't go for a 3", stick to a 2.5 or 2.75 decatted.
10 January 2013, 07:35 PM
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Hi Busta, I reckon I should be able to make it on Saturday. I don't think I'll bother with a Dyno run though (I only had one at SC a few weeks ago) unless somebody thinks it could help troubleshoot my problem!
There's no induction kit, just a K&N panel filter which the previous owner had fitted.
EDIT: Just seen your other reply.
I thought the PPP system was already decatted in the centre?
There's no induction kit, just a K&N panel filter which the previous owner had fitted.
EDIT: Just seen your other reply.
I thought the PPP system was already decatted in the centre?
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10 January 2013, 07:42 PM
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Not that I'm aware of, it seems to go:
Turbo -> Downpipe (sports cat) -> Horizontal midpipe (no cat) -> weird flange type arrangement -> centre section (with resonator) -> Backbox
I'm sure I read somewhere that the PPP cars come without a cat in the midpipe, and sports cat in the downpipe... but I could be making that up.
If the car DID originate with a midpipe cat, I guess that's what the previous owner has had "hacked" out.
Turbo -> Downpipe (sports cat) -> Horizontal midpipe (no cat) -> weird flange type arrangement -> centre section (with resonator) -> Backbox
I'm sure I read somewhere that the PPP cars come without a cat in the midpipe, and sports cat in the downpipe... but I could be making that up.
If the car DID originate with a midpipe cat, I guess that's what the previous owner has had "hacked" out.
10 January 2013, 07:53 PM
#10
Not that I'm aware of, it seems to go:
Turbo -> Downpipe (sports cat) -> Horizontal midpipe (no cat) -> weird flange type arrangement -> centre section (with resonator) -> Backbox
I'm sure I read somewhere that the PPP cars come without a cat in the midpipe, and sports cat in the downpipe... but I could be making that up.
If the car DID originate with a midpipe cat, I guess that's what the previous owner has had "hacked" out.
Turbo -> Downpipe (sports cat) -> Horizontal midpipe (no cat) -> weird flange type arrangement -> centre section (with resonator) -> Backbox
I'm sure I read somewhere that the PPP cars come without a cat in the midpipe, and sports cat in the downpipe... but I could be making that up.
If the car DID originate with a midpipe cat, I guess that's what the previous owner has had "hacked" out.
Wouldn't worry too much fella, I'll have a listen on sat or maybe jb or someone can take it out for you and have a listen.
10 January 2013, 08:34 PM
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I shall check that tomorrow 
I just had a quick look under the car with a torch and couldn't make out exactly where the lambda sensor is. I guess somewhere after the downpipe cat but before the would-be centre section cat?
I actually noticed from the photo I posted at the start of this thread, a bit of black soot coming out from one of the clamps. I've just wiped this off now and nipped the clamp up a bit - I'll see if the soot is present after some driving tomorrow.
I doubt that would be whistling though, would expect a more traditional raspy/blowy sound I guess.
I just had a quick look under the car with a torch and couldn't make out exactly where the lambda sensor is. I guess somewhere after the downpipe cat but before the would-be centre section cat?I actually noticed from the photo I posted at the start of this thread, a bit of black soot coming out from one of the clamps. I've just wiped this off now and nipped the clamp up a bit - I'll see if the soot is present after some driving tomorrow.
I doubt that would be whistling though, would expect a more traditional raspy/blowy sound I guess.
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