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Discussion Starter · #1 ·
I just installed a greddy boost gauge. when the car is idle, the reading is about -0.4 kg/cm2 and the highest it will read is 0.6 kg/cm2 when the car is in 3rd gear. is this normal?
 

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dark_rex you so nice

I prob wouldn't take the time to do searchs for people!
 

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Discussion Starter · #4 ·
but what i've heard of the normal reading should be at least around 1.0 kg/cm2 (14.22psi) at 5th gear. i only have at most 0.6 at 5th gear. is there a problem with the gauge? thx!
 

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twivy said:
I just installed a greddy boost gauge. when the car is idle, the reading is about -0.4 kg/cm2 and the highest it will read is 0.6 kg/cm2 when the car is in 3rd gear. is this normal?
Hello :)

The reading you see on the boost gauge when the car is idling is the manifold vacuum. If is - 0.4 kg/cm² or -400 mmHg, that's good. This is basically telling you how "tight" your engine is. -0.4 is good, -0.45 is better, but it's not critical.

I find strange that your car does not boost higher than 0.6 kg/mm. IIRC, it should be 0.9 - 1. If it doesnt read any higher, then either there is a leak or your turbo is not making enough boost. Does the car feel fast or not so fast?
 

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You are correct, it should be around 1.0kg/cm2, but as to why you have less, I do not know.

Where did you tap the signal for the gauge? Also, do you have some form of aftermarket boost control that could be malfunctioning?...I say this because the stock spring pressure is about .6kg/cm2.
 

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Discussion Starter · #7 ·
Does it have something to do with my A/T transmission?
I don't really feel slow about the car. and i didn't really have chance to get a ride of a fast wrx yet.

I connect the y shape joint with the manifold as the factory boost gauge instruction shows. does all boost gauges use the same kind of connection?
 

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Discussion Starter · #8 ·
I don't have any boost controller installed. so what you mean is the spring pressure affects the boost reading?
 

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Having a negative boost reading at idle or while cruising is an excellent way to be sure that you didn't accidentally get the Diesel version of the WRX.
 
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