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Hey there,

I've just noticed this today, as I don't really boost my car often but after I took it for a run to make sure it was running well after I was working on the motor I noticed that the car is only boosting to about 2-3PSI?

It had a boost control on it, which was turned right down because I just had a forged rebuild so I took off the boost control and connected it normally, still seems like it's only boosting at 2-3PSI on the stock boost guage as well as a aftermarket boost guage.

Any ideas? All hoses etc seem to be connected well checked everything I could...

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https://www.sau.com.au/forums/topic/144683-boost-problem/
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  • 2 weeks later...
when you say 2-3,do you mean 2-3 on the stock gauge?

because that is normal...

Yeah, I do mean on the stock guage. My other guage ain't that great so I can't go off that either.

I'll go over the car this weekend T04GTR make sure all that is alright.

But, Waz - so it's normal only to go to 2-3PSI on the stock guage then? So, It's just me? :(

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https://www.sau.com.au/forums/topic/144683-boost-problem/#findComment-2728776
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Stock boost under 4500rpm is 5psi and 7psi over that.

So 7 on the guage is 7000mmHg or whatever the multiple is, which is about 1 bar I think? So you should see about halfway between 0 and 7 when on full boost.

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https://www.sau.com.au/forums/topic/144683-boost-problem/#findComment-2728893
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stock gauge is in mmHg (that millimetres of mercury)

and the conversions are: 760mmHg = 1bar = 1atmosphere = 14.3(ish) psi

and the stock gauge is read at x100mmHg

so...

+7 on the stock gauge actually means 700mmHg which is a tad under 14psi

and so on a stock R33, which runs 5psi then 7psi higher in the rev range, you would expect the stock gauge to read between +2 and +4 on the stock gauge

that is 100% normal :D

from my experience, the stock gague is pretty accurate. its flaws are that is it hard to read because of its units aren't commonly talked about, its in a hard position to see, and that it can't read over 14psi

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