hi to all. i was just wondering what is the max boost on the stock trubo for the WRX.

 

15.7 psi safely.

Someone else will try to tell you differant

 

45 there I told you different.

The WRX runs 13.5 stock. I don't know if you mean max possible or max from the factory.

 

max possible on the stock turbo. thanks for all ur help

 

meh ive heard 17 but i dunno. ive peaked at about 16 a couple times and its ok.

 

+1.....

 

Cobb has their stage two map set at 15.8 plus or minus 0.5.

 

when my EBC failed (long story ) and spiked, it replayed 1.65 bar roughly 21-22psi on my stock turbo. the only reason why (i think) my engine didnt blow was that when it happend my 100% atmos bov opened and let out the boost by itself. i immediately pulled over to fix the problem.

on another occassion my friend set his MBC wrong (instuctions wasnt clear) and it was set to full boost. we took it for a test drive and in 1st gear he topped off at 20+psi according to his autometer boost gauge.

Moral of the story: Boost controllers are EVIL!.... EVIL i tell you! lol

 

there needs to be some type of fail-safe so you don't break anything when your engine hits high boost for one reason or another

 

This question is meaningless. You mean the maximum theoretical boost? That's limited by the material strength under thermal stress of whatever your turbo is made out of. ( I don't know what the construction of the TD04 is)

And you mean the maximum practical boost? There's no answer! People blow their motors at stock boost and other people run 18psi with a clipped wheel and some people run 20+psi on high octane.

The real question you have is "what boost setting do expert tuners feel comfortable running on the stock turbo such that people don't blow engines and sue them / damage their reputation as a tuner". To that I believe the TXS stage 3 is 16.5 psi? And the target for Cobb stage 2 is as MonkeyAB stated above

 

What year WRX do you have and what’s your plan for the car? Like verc said x amount of boost might be safe for 1 car and not another depending on mods etc. From what I’ve read the oe turbo starts to blow hot air once it hits over 17 psi but that doesn’t mean it’s safe to slap on a MBC and turn it up to 17 psi on a 04 with the oe upipe.

verc

I’m no expert on the subject but the target boost levels you are talking about are for off the shelf maps so I would think they would be a little more conservative than (depending on conditions) the target boost on a custom tuned car with the same mods.

BTW, I live at around 500’ above sea level, my car is Cobb stage 2 + an upipe and my car will hit 16.6 psi when it is cold outside, my egt’s never go over 1550 and my plugs have never shown any sign of det..

 

Yeah I assumed the poster was asking this question b/c he was going to take an MBC and just ran as much boost as we told him to. That's why i feel that those off the shelf maps are pretty good metrics.