I'd seen a lot of posts on Briskoda forum about people removing the pre-cat from the exhaust downpipe (not to be confused with the normal CAT) and seen some great gains in terms of power and fuel economy (some members reporting a gain of 5MPG). Most people do this themselves by removing the 4 bolts by the turbo, remove downpipe and take a hammer & chisel to the pre-cat. I didnt fancy doing it myself so I booked mine it at my local trusted garage (ABP Motorsport in shavington, Crewe) and they did the work in just under an hour
After a bit of ECU - adapting (on the bypass) I'm happy to report the following:
- More turbo sound
- slightly deeper exhaust note
- faster turbo spool up
- pulls harder in the higher revs
So to sum up, it's a win-win for me
I'll report back on the MPG effect at a later date.
I should also point out that this WILL NOT CAUSE YOUR CAR TO FAIL AN MOT! (unless the requirements change again). VW fit it to aid cold-start emissions which isn't tested as part of the uk MOT.
It's worthwhile changing the manifold gasket and the nuts while your doing it (parts are only about £8 from vw)
See here for more info, part no's and photos:
http://briskoda.net/forums/topic/197778-pre-cat-removed/Cheers,
Graeme