im looking at mods and doing a de-cat i would like to know if there is a cat in the up-pipe or not in on the 03 cars, and if it doesnt have a cat is it still a good idea to replace.

p.s what and where is the up pipe anyways, downpipe centre and back i understand. but not up.

 

Always confuses me too.

If its an up pipe, then surely its the pipe that goes up.

But if your looking from the other end, does it become the down pipe.

Now I know where the tail pipe is, thats easy!

Diagrams please........

 

Up pipe goes up to the turbo.
Down pipe goes down from the turbo.

 

The up-pipe connects from the manifold (underneath your engine)to the base of the Turbo,Hence the name Up-pipe (Up from manifold to Turbo).I think you know about the downpipe.

I was told that there is NO cat in the 03 up-pipe.

Zippy

 

No cat in the up pipe on an MY03

 

so it isnt worth replacing the up pipe with another pipe with no cat in then I guess.

So my upgrade consists of new down pipe, centre section with hi flow sports cat, and a back box. and a custom ecutek re-map.

with just the sports cat in the centre what is the likelyhood of the car passing an mot test ??.

 

No CAT in the uppipe of an STI8

 

Never has been an up-pipe cat in any of the STis, the 7 didn't either. I believe Pete Croney has said that some WRXs seem to have inherited an up-pipe cat, some haven't.

Up-pipe as said above goes from your headers (manifold) to the bottom of the turbo - gas flows up, hence "up-pipe". There is no need to replace it if it is already decatted, but there will be a small benefit if you do, as a good aftermarket one will provide "cleaner" flow. If you're changing it, get your headers ported at the same time. Or better still get new headers (some even come with the up-pipe). Could do the turbo whilst you're at it . . . . See how quickly your money can get spent?