I'm looking for an up-pipe for my WRX, and have been looking at the options, and have developed a couple of questions:

Will up-pipes without flex sections break?

Which up-pipes throw CEL's? Which don't?

In someone's humble opinion, which is the best?


Thanks for the help.

 

Break - no, but are posibly prone to develope leaks at the lower flange (it helps to use thick aftermarket gaskets & leave turbo brackets unhooked)

CEL - only a P0546 (even a gutted stock pipe can get this)

Best? I'm partal to any pipe with a flex joint... STi uppipe with no cat.

 

so why are you prone to ones with flex sections? do they offer any real advantages (other than the leak)? and I read somewhere that the sti pipe will throw a cel, unless you get the 2.2 ohm resistor fix or something like that.

 

any problems with the perrin up pipes?

 

i read somewhere that the 2.2k ohm resistor fix tricks your ecu, and prevents it from reading other things, not just the egt??

 

so with the VIshnu up-pipe installed you haven't had a cel? I was looking at vishnu's stage zero, or maybe just their uppipe, but I don't wanna have to worry about a cel or something like that?

 

I have installed a PDE & a Perrin non-flex uppipe.
Very nice pipes & good fit.
I haven't heard of any leaks on either, but we used thick gaskets & left the turbo loose in its mounts so it can move around...

There are some horror stories about pipes that leak no matter what & sometimes is related to a warped flange.

If it is a daily driver & you're not going to be pushing 350hp+ a flexible uppipe is fine... flex joints don't last for ever but the risk of developing a flange leak is realy reduced...

I personally use a gutted stock uppipe... for cost over performance I can't complain & it is WAY better than the way it used to be...

My CEL is because of crusing in freezing weather & the pipe is out of the "expected" temp range... yes I have a 2.2k ohm 1/2watt resistor in the system... no more CEL

 

glwagon- thanx for that info about flex uppipes for daily drivers.

so do you guys recommend an uppipe even with a Utech stage0?
or would i be okay with no uppipe? i dont want to go through
with changing the uppipe, but do want a little more punch
from stock. currently i have a hacked intake with K&N with
Blitz NUR catback. i want a tad more power.

thanx for your help.

 

Once you get rid of the uppipe cat (gutted or new pipe) this will add at least 5-9 hp. The real benifit is not worrying about the cat breaking up into the turbo...

If done safely (yea right) adding a little boost makes a diffrence the last guestimate I've heard is 1psi = 10hp. Factory boost is around 13.5psi. The stock ECU has been able to handle psi into 15psi range under WOT (wide open throttle)

do some searches on safe boosting a MBC isn't a great solution... I won't recomend it for a daily driver...

I personally use a dual stage boost controller (factory & MBC) with a switch under the steering wheel. "boost on demand"

https://www.i-club.com/forums/showth...+boost+control

Do some searches & go from there...

 

had my mrt flex uppipe for a good 20k miles and no leaks (did install new gaskets) and no cel's. anyways, just my 2 cents.
--neil