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I have been searching on both clubs, tried this one first, information about what is the maximum boost I should be running with stock a WRX. I would also like to know what gear I should be able to calculate this in. And approximately what rpm range I need to rev to to acheive maximum boost.

I finally have a boost gauge and I maxed out at about .96 hkpa which is about 14 psi. But I don't remember what gear it was in. Does that sound normal?

I am intesested in getting an aftermarket MBC but it won't help me if I don't know what my factory maximum boost is.

I see that there are a lot of people here with after market MBC's so I know someone out there can help me, PLEASE!!!!!!!!!!!

Kurlee Daddee
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KurleeDaddeeWRX said:
I have been searching on both clubs, tried this one first, information about what is the maximum boost I should be running with stock a WRX. I would also like to know what gear I should be able to calculate this in. And approximately what rpm range I need to rev to to acheive maximum boost.

I finally have a boost gauge and I maxed out at about .96 hkpa which is about 14 psi. But I don't remember what gear it was in. Does that sound normal?

I am intesested in getting an aftermarket MBC but it won't help me if I don't know what my factory maximum boost is.

I see that there are a lot of people here with after market MBC's so I know someone out there can help me, PLEASE!!!!!!!!!!!

Kurlee Daddee
(THE ORIGINAL)
That's about right...You wont see that in 1st gear but 2nd onwards. You should see it hitting around 14psi (mine 15psi) at around 3.5/4k maybe. It's been a while since I had the car stock.

My MBC is set at 15psi and I get 14psi in 1st. The stock boost in 1st is around 9-10psi.

MichaelWRX
 

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I wouldn't calibrate for more than 16psi in 4th gear. That way you shouldn't spike much over 16.5psi in 5th. Boost will be lower in the first three gears as michaelwrx pointed out, especially in 1st and 2nd.

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Is thier a recommended limit as to how much boost the pistons and engine can handle. I've heard that about 17 psi is the limit. I'm thinking about turbo upgrade, but don't want to dramatically increase the chance of blowing it.
 

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what about wear issues? when i'm out at the track or the 1/4, the boost just stays at 15psi through all the gears since im WOT. if im running like that for all day, whats gonna happen to the car?
 

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Hmm, 17PSI is about the limit on Stock Turbo? Curiously, what is the deciding factor to let one know how much boost can be? Is it EGT? Anyone in the know?

Thanks,
Carlo
 

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well yeah, egt factors in, but its more of the limits of the turbo itself. anywhere above 17psi and you're in the danger zone - the turbo is spinning way too fast and if something goes wrong your car could explode. well maybe not explode, but bad stuff could happen
 

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Well my take would be that at 17psi or so the TD04 is moving way out of it's efficient zone and is gonna run hotter than hell. On my WRX I have seen EGTs of 900c with the TD04, but have not gotten over 850c yet with the VF30. Also, I should think that at those kinds of boost levels the ECU cannot adjust to adequate fueling without some kind of additional engine management, be it piggyback or standalone.

-Pace
 

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On the stock system 17 would be taxing the turbo a bit much. 17 p.s.i. on a track for a few runs would be safe, but not a daily driven p.s.i. on a stock turbo and fuel. The internals should hold up pretty well though, after all, the wrx was built to be a turbo with the low compression ratio to comphensate for sudden surges of power i.e. forced induction. In any case, Turbo XS stage 4 privlegies are running safely 18 p.s.i. daily on the car, of course on a different turbo and fuel system, as well as exhaust and an new air filter (which really does not make that big of a difference) I like my set-up. I would have gone with stage 4 Turbo XS but I decided to ditch the air filter for an injen race division and get an MRT to support the high temperature the new system gives. Therefore I created my own stage 4 that holds up to 18 maybe 20 for a few good passes without hurting anything. And I don't even have a fuel pump:D
 

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I haven't dyno'd yet but I am expecting around 285-290 to the wheels!!! On pump gas.... I plan on getting a fuel pump,some pulleys,porting and polishing my throttle body, and getting some cusco headers within the next month!!! Putting me swell over 300 hp to the ground!!
 

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What do you mean WOW!! I should be saying that to you, my car will blow up before I even know what's goign on, you on the other hand have the smart mods, protective maintainance with gauges, you know what's goign on in your ride.. I say WOW to yu buddy.. your heading down the not so greedy path........
 

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hehe, true. but remember that i eventually want my car to perform somewhere near the same level as your car, so inevitably we all end up in the same situation. im just astounded at how much you've done to your car in only 3k miles (i think you had said 3k before)
my car is at 4400mi and i havnt done nearly as much. its just amazing at how powerful some ppl have been able to get these wrxs. you're among a very elite few:D congrats!
 

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AecannonRacing said:
Thanks a bunch!!! But in any case, my car has 1052 miles on it!!!!!!!!!
I have actually read some dyno reports on MY01/MY02's at different ages and that even around 20,000kms they produce more power than when they are 10,000km's old.

MichaelWRX
 

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AecannonRacing said:
Thanks a bunch!!! But in any case, my car has 1052 miles on it!!!!!!!!!
you gotta be kidding me. only 1k miles on it? have you even followed the break in schedule? with that much stuff on the car already...geezz...i wonder how thats gonna work out for your car long-term. on the otherhand, you're ages ahead of those who are just starting to mod their cars. i didn't start till 3k mi.
 

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AecannonRacing said:
Cool, that's like a good wine. Aging a car can make it better! Do you know where you saw this? Sounds interesting.
Somewhere here in Aus. I will try and find the link.

MichaelWRX
 
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