Hi, I need to replace the up pipe on my 01 wrx as the cat is going but cant seem to get a definate answer as to which pipe I need. Magnex tell me that the up pipe they supply for 01 onwards does not have a sensor boss on it , the sti up pipe does have a boss on it but thats listed as 02 onwards, they then tell me that the wrx didnt get a cat in the up pipe till 02 which confuses me even more. I definately know its got a cat in the up pipe as its been diagnosed by my local scooby garage. How can I tell (without ripping the engine apart) if i need the pipe with boss or the pipe without a boss as my car seems to be an inbetween model that has 01 and 02 parts on it.

 

I forgot to mention that its a european import from belgium, would this make any difference ?.

 

Heloooo, anybody there.

 

both pipes are exactly the same fitment, the difference being (as you have mentioned) the temp sensor boss....................

simply purchase the later style with the boss!!
if you need any help, feel free to email/pm me and i'll sort some assistance for you

alyn

 

I just replaced my up pipe,and the pipe i bought had a boss.It was not needed so i plugged it with a bolt.

regards mark

 

I got an '01 WRX, and it had a cat in the up pipe....I know cause I took it off

 

Thanks for the info, ill just order the one with the boss then.

 

i've also got a 01 wrx and i went for the one without the boss,reason being that you can then disconect the cat on fire sensor and replace with a 0.5 watt resistor where it plugs in,as i know of one sensor breaking off in the up-pipe and going through the turbo,and also i figured less turbulence in the up pipe gases due to no bolt hole or sensor sticking through.

 

Does the decat make much difference performance wise, ive already removed the other 2 cats, will removing the 3rd make much difference. Im running a boost controller so spikes wont be a problem, will fuelling need to be remapped.

 

i'm not sure to be honest as i did all my cats at once,the downpipe cat is the main restrictor of turbo spool up and flow,i'd say the up-pipe is more a safety precaution as running more boost can weaken the cat and if it collapses it goes through the turbo.it's also a pain to do,not hard but time consuming as you have to remove other things to get to it.

 

can anyone be certain about a decat down pipe passing an MOT with the standard zorst and cat in the centre pipe? cheers