S3 Precat

mramage

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There are very few threads on precat removal for an S3. Most mention change of downpipe, but that's a very visible change. Has anyone actually done this? Any noise, MPG or performance difference. It seems like a nice cheap mod, especially reducing EGTs. Any downsides to this, anyone actually removed it care to comment?
 
Sounds good. I'm keen to try and write up?!
 
I think it's a lot more popular on the 2wd cars as people where able to do this themselves, but with the 4wd and having to move the diff out the way to get to it I don't think its a job for doing on drive hence why not many S3 owners do it. I did want to but when I looked into it, it was too difficult to do myself without a ramp so rather than pay to have it done and then pay again in a few months as I was having the full exhaust done anyway I waited.

If you have a friend or know someone who has access to a ramp I'd say go for it people see good improvements!
 
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I think it's a lot more popular on the 2wd cars as people where able to do this themselves, but with the 4wd and having to move the diff out the way to get to it I don't think its a job for doing on drive hence why not many S3 owners do it. I did want to but when I looked into it, it was too difficult to do myself without a ramp so rather than pay to have it done and then pay again in a few months as I was having the full exhaust done anyway I waited.

If you have a friend or know someone who has access to a ramp I'd say go for it people see good improvements!

Ah, that may explain it. Thanks!!
 
I had the pre-cat removed and my before dyno run (otherwise std car) was 280ps so around 10-15ps gain at the top end plus slightly better spool up. No noise difference though.
 
I had the pre-cat removed and my before dyno run (otherwise std car) was 280ps so around 10-15ps gain at the top end plus slightly better spool up. No noise difference though.

What was the after dyno result? I'm assuming stage1 remap here. Also, any economy difference?
 

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