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How much boost can an internally standard RB20 take. I am talking reliable boost, not how much before it goes bang.

The reason I ask is:

I was told when I bought the car that this block is extremely tough, so can handle the occasional high boosting. So, I have been running mine at 1.5 bar for nearly two years now. Just cause it can boost this high doesn't mean it reaches this every gear change. Far from it. I may actually only hit this boost once a month, but it is there when I want it.

Today I went to get my car dynoed. Came back $270 poorer and missing an extra 20 rwhp that I used to have and 0.3 bar of boost. He says I will blow a piston if I run it at this boost, but I haven't (yet). There is no detonation problems at 1.5 bar, and the fuelling is all ok.

Thoughts peoples?

So will my car die tomorrow if I wind the boost back up?

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on australian fuel (98 octane) i dont thinky you should run over 1bar (14.5psi) with octane booster and the right tuning im sure 1.5 bar is possible but over time the engine will breather more and wear out due to such high boost levels.

im running my t04 at 14psi with a bigger pump and std injectors at 90% duty cycle

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Is the T04 the standard Turbo???

I have standard engine/turbo/intercooler with 3'' exhaust, Blitz BOV, HKS filter and Turbosmart Bleed Valve wound out to 0.95 bar. (14PSI)

The car runs fine and I love the boost response. I have no problems with running these sorts of pressures, but I am waiting for the turbo to say goodnight, so I can give her some real boosting!!!

My car is religiously serviced every 7500 to 10000 k's and she gets the good oil!

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Originally posted by GILTY

Is the T04 the standard Turbo???

Where did that come from?

Anyway, NIZ30, if you're running the standard turbo (a T3 derivative), at 1.5 bar, then you've been extremely lucky. The ceramic wheels are notorious for parting company with the shaft when run at much above .9 bar, and are often then ingested backwards into the engine. And the ceramic material is a wonderful cylinder honer.

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yeah i think you should leave the boost if you dont want any problems, if it was running fine then why did (whoever you took it to) wind it back? running 1.5 bar is too much for the factory turbo and you might not notice detonation but doesnt mean its not occuring. if you wanna run high boost get a FMIC, management, and an aftermarket turbo that can handle the high boost pressure

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I got all the things people are saying : -

Trust TD06-20G Turbo

Trust FMIC

Trust custom exhaust manifold (high mount turbo)

Trust Wastegate

Injectors (i think?)

Fuel pump

The car runs fine at 1.5 bar there is no problem with that. But can the engine withstand this boost?

Saying this, I am a bit disappionted with my 239hp considering the turbo I have. I need to sort out the fuel problem and think an Apexi S-AFC might be in order.

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I am pretty certain that the interanls should be fine on 1.5 bar, but it depends what sort of period you want to run this boost, as bigger boost equals increased engine wear.

You should check to see if you do have aftermarket injectors.

Going by the dyno results the fact that you dropped your boost pressure by .2 bar and only lost 20rwhp is good, as normally the rule of thumb is for every 1 pound boost you should make 10hp..? (correct me if i am wrong) so therefore you've dropped close to 3 pounds and only lost 20 hp.

Maybe you should look at getting adjustable boost so you can run say 1bar low and 1.5 high... I'm sure your turbo will be able to handle it, as well as your interanls, and you have a bigger pump so the injectors and some sort of aftermarket management is all you would need..

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