MK5 Golf GTI
All Things Mk5 => Modifications & Technical Area => Performance Modifications => Topic started by: chrisvectra on November 13, 2014, 09:06:12 pm
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I bought my Golf a few months back
http://www.mk5golfgti.co.uk/forum/index.php/topic,87860.0.html
Fantastic car really pleased with it the only downside was the exhaust.. To put it bluntly it was was Loud and I mean Loud!! and as I do lots of motorway miles in it decided it was time to quieten it down... (it was starting to do my head in) So a trip to powerflow was arranged and also parted with some cash , I now have a car thats alot quieter and a hell of alot faster which im very confused about..
The car had had the cat removed and basically was a straight thru exhaust from turbo to tail pipe...
Hence why it was loud.. But now there are are boxes in place and a decent exhaust fitted the car now has a nice sound.. But also has become alot faster and I mean alot.. It pulls hard really hard now and wheelspins and wakes up the traction control like it never has before.. So whats going on?
Confused that a exhaust could make such a difference
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Don't have the answer myself but work the problem backwards.
If you had an exhaust fitted, and only that, think about what it can affect on a diesel. Probably boost related, maybe even fueling also due to 'dodgy' sensor outputs?? Just a thought.
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The only thing I can think of is back pressure as there obviously wasn't any before, But to change the characteristics of the car like it has has me baffled..
The car ran fine before with the straight through exhaust on and the car didnt have any warning lights on at all its now just so different to drive as I've explained..
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If the old one was to big (diameter) and with no cats then as above you might have lost back pressure which will cause a loss of power, I would have thought it would make as much difference as you've described though....
Sounds like it was a cheap one so maybe it was poorly fitted which might cause other complications?? I'd be interested to know of anybody has the answer.
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If the old one was to big (diameter) and with no cats then as above you might have lost back pressure which will cause a loss of power, I would have thought it would make as much difference as you've described though....
Sounds like it was a cheap one so maybe it was poorly fitted which might cause other complications?? I'd be interested to know of anybody has the answer.
It was a hand made put together system made from different parts so wasnt ideal and very loud hence why I felt the need to change it....
I dont know why the car is so much faster now but im happy it is lol..I would like to hear other views on this matter please
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sounds like the old exhaust must have been restricted some how
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sounds like the old exhaust must have been restricted some how
The old system had no restrictions at all bud it was just a straight thru system which is why it was so loud..I Have a feeling that it must be back pressure related as nothing else on the car has changed.
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Either way you win, sounds better and extra power you weren't expecting :wink: sorted
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Either way you win, sounds better and extra power you weren't expecting :wink: sorted
Im happy in how the car performs fella, even more so no just confused in how or why a exhaust system could make the car so different..
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anyone else have any clues?
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The only way to prove it would be to put the old one back on the car and see if it goes slower again. I think as said before that it may have been a lazy sensor at some point, which then fixed it's self in removal and refit.
Also i know that the intake system is sensitive to airflow speed, if your in take sensor has a too big pipe, it can't measure the in coming air accurately. Could be the same for the exhaust...
Or a dirty sensor, that got cleaned up on removal ?
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I belive the less backpressure the better on a turbo car.. Maybe not the case with a smaller k03 turbo though..
When i removed my milltek for a straight pipe coming out under the side of the car with 1 silencer i felt gains.. Allthough i belive the milltek restricted my car
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The old exhaust has gone in the bin bud so couldnt do a back to back test on it. also there wasnt any sensors to remove from the old system so I dont think its sensor related either..
I have spoken to the powerflow guys and whilst there not 100% certain they think it maybe back pressure related..