Modified OEM Downpipe

Chris-32T

Registered User
i thought i had posted up about this but had a quick search and it would seem like i haven't

Anyway i had been looking for a second Downpipe to modify (take the pre Cat out) but as luck would have it a few weeks ago whilst i was at work a friend of mine spotted this on another forum and aquired it for me already gutted which was a bonus.

Pic of gutted Downpipe



Once i had picked it up i got in contact with another friend of mine to see if he could run a bead of weld around the inside to try and smooth it out to aid flow.

Downpipe after Welding



And thats how it sat for a few weeks until i found the time to fit it, finally managed to get it sorted yesterday an absolute PITA job to do on your drive by the way, come MOT time im either going to rent a ramp or pay someone to fit it lol.

Quick pic to show OEM Vs Modified OEM



Modified



Now thats on the car i have a RR'd session booked for Thursday morning to run the car in its current guise, once finished there i will be heading off to get the APR Stage 2 software loaded onto the car then hopefully back to the RR to see if there are any significant gains to be had.

Car Spec as it stands

APR Stage 1 V2 software
Forge Front Mount IC
De-Catted OEM downpipe
Secondary Cat delete pipes
Milltek Cat back non Res

Waiting on a Pipercross filter hopefully here Wednesday

Will keep you guys informed with Pics,Vids and graphs all being well :)

Cheers

Chris
 
Last edited:

Chris-32T

Registered User
To answer your questions, firstly getting the downpipe off is a bit of a chore but doable, I did it on the drive however a ramp would be much easier. With regards to removing the cat I wouldn't know I bought my downpipe already gutted so I could keep the OEM one intact come sale/trading in time.

But looking at the inside of my OEM pipe, once it's of just use a hammer and chisel to remove the insides. With regards to MOT time because there is no physical evidence or tell tale sign there isn't a cat in there then how would the tester know ??

Would possibly fail on Emissions but then there are ways around that aswell ;)

Best bet is to try and find one already gutted or a cheap second hand downpipe and gut that, once fitted the car pulls stronger and breathes a whole lot easier.

I would expect to gain between 5-10 bhp possibly more and from what I've seen/read the gains are equivalent to those seen with the milltek etc downpipes.

Cheers

Chris
 

Kelza

MODERATOR
Staff member
Moderator
Thanks Chris ,it just seems a cheaper option than a uprated downpipe (1k) just trying to work out what's best at the moment ,cheers
 

Chris-32T

Registered User
Well I paid £300 for my gutted downpipe, and fitted it myself so much much cheaper, but even if you paid someone to fit it the chances are it still would be less than half of just the cost for a milly version with the latter yielding no extra benefits. So it's a no brainer IMO.
 

45bvtc

The Older I Get The Better I Was
Supporter
Gold Supporter
Will this be easy to spot by the MOT tester? or will you have to temp refit them for the test?

ONLY when sniffing the exhaust, I'd guess.

Run a 'fully-cated' RS3 end-to-end with Bluey's sans secondary cat(s) system and you can certainly smell 'a' difference that ain't just down to body colour...
:whistle2:
 

Dave Hedgehog

Registered User
ONLY when sniffing the exhaust, I'd guess.

Run a 'fully-cated' RS3 end-to-end with Bluey's sans secondary cat(s) system and you can certainly smell 'a' difference that ain't just down to body colour...
:whistle2:

I guess it depends on how much effort they are going to apply to check the cats after the change to the MOT test
 
Top