Hi guys

I found a cheap de-cat downpipe from a classic I assume this will fit my uk bug? Just the lamda is in a different place? I assume this won't cause issues? Car will be re-mapped anyway.

Also wil the length be ok when bolted up to a newage cat back system? Won't be too long or short?

Thanks all

 

I'm not a 100% sure but I don't think this will work mate. If you had both classic cat pipes i think it would work with a bit of tinkering but mixing the two creates an end length which is the wrong size (either too long or too short).

Hopefully someone will come along and confirm mate

Good luck

 

I've before fitted full exhaust from classic on mine and has been fitted without the problem,yes one hanger on backbox has been on wrong place,which can be rewelded,but we are not...

This issue with O2/Lambda sensor is nothing to worry


Jura

 

Ok mate thanks foe the help
Will a classic up pipe fit a bug uk wrx? As he has 1 of them as well

 

Hi jura

Its only the dwn pipe from a classic the centre section and back box ate newage

 

I think the classic Downpipe is longer than the newage downpipe by about 4'' but the classic centre section is shorter than the newage by the same difference. If you had both pipes then it would fit but just the downpipe will mean that your hanger won't line up.

Bide your time for a newage one mate, there's always plenty around the for sale section.

 

Thanks mate

Do you know if the up pipes are the same?

 

Bug up-pipe has a Cat and EGT sensor
Classic up-pipe no Cat or EGT and should fit no problem although you will have to either use an EGT fix or have it mapped out.

 

Thanks mate its an after market stainless 1 so it has a place to put a sennsor but worse case will just map it out

It assume a bug is a 2 bolt flange?

 

If after Market one check bore size as some are far to big and hinder spool rather than improve it, also avoid any with a flex joint in.

 

Not sure,i've before full exhaust from classic and has been fitted nicely on my wagon


Jura

 

No problem mate. I only know as I made the mistake myself

Not sure on up-pipe sorry

 

+1

These oversized Up pipe with flexi joints will kill your spool,if Up pipe try source STi up pipe,which don't have EGT,but can be mapped out by mapper

Or try contact Harvey for Up pipe

Jura

 

Yea I cheecked bore size and was 2" and its the slip jointed type.

Are the classic pipes deffo longer and nit shorter?

 

This pic explains it better than I could mate:



Some aftermarket downpipes do come as 1 piece. I.E sections 1 & 2 are joined together to make your exhaust 3 pieces from the turbo back. Hope that helps mate

 

Thanks a lot mate I know what I need now

 

No worries

 

Reanimating this thread.

Do you simply screw your O2 sensor into the boss on the classic pipe, or does it need remapping to recognise that the O2 sensor is before the CAT?

Everything I've read points to the classic downpipes being shorter, the centre sections being longer than later models.

 

Hi there

Yes I would screw sensor on classic downpipe,we are run this downpipe on our wagon,I wouldn't think you will need to get car remapped,but if car hasn't been mapped for decat exhaust then you will need get car mapped or at least check'd

Hope this helps

Thanks,Jura

 

Cheers. It's a bog standard Forester 2.5XT at the moment with 4 piece exhaust and O2 sensor at the lower end of DP. The Classic downpipe I'll be putting in has a cat on it; but I guess the O2 in the classic position it will think it hasn't.

 

generally car doesn't need remapped to move the front o2 behind the turbo (top of the downpipe spot). This is how I have my car setup along with JDM/classic downpipe (shorter than a UK wrx one) and classic length centre section (longer than a UK one).

The rear o2 you can remove and have it mapped out or put it in the rear o2 spot (bottom of the downpipe, would normally be after the main cat) and still have it mapped out.

 

If I did that with the rear O2 but didn't map it out, I'm not going to get error codes all the time am I?

 

if the rear o2 is there without the cats you'll get a catalyst efficiency code on occasion. if the o2 is removed then you'll get a no-response code.