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Darn it aye, was hoping I wouldnt need to get a boost gauge

I thought they were either all inaccurate past the standard boost levels, or they were pretty much spot on.

I believe they are electrical gauges. Alot of the top brands sell electrical ones too, does this mean that they are also relateively inaccurate? Perhaps the boost sensor on the R34's isnt as good quality.

There is no real reason why the stock boost guages would be highly innaccurate, unless the sender has failed?

IMHO usually people go for aftermarket boost guages (and oil pressure and water temp) as they have more increments and are easier to read. With only 4 increments or so on the stock one its quite hard to read accurately. The difference between 12psi and 14psi is hard to judge for example, and one is safe and the other is possibly not.

ive got autometer cobalts on mine (boost/vac on an xr6 turbo). my gauge is pretty accurate when there is constant acceleration (auto, gauge is mechanical), however when i floor it and it kicks down a gear, it spikes up to 10psi, and then returns to 6psi.

my gauge also lags abit because i have kinks in the nylon tubing, which i will be replacing soon.

Its good to have a nother gauge but not really needed.

In my R33 I occassionally use an old pressure gauge I have that is fairly accurate to check the boost and see where it sits on the factory gauge.

I dont leave this connected and just have a glance at the stock gauge to see eveything is ok.

Stock gauges (iff same as R33) are a pressure transducer that sends a 0-4.5v (I think) signal to the dash.

I took a multimeter to it once but can't remmber the vs at atmospheric pressure (May have been 1.25 or 2.25v)

So it would be a 2bar MAP sensor...

0-1bar is vacuum

1-2 bar boost - due to turbo

+1 on the gauge would be about 14psi-15psi

Yeah Ive got a pivot stepping motor boost guage on my r32, it seems the stock one is pretty close.

With just a cat back and filter its running 0.7-0.75bar which is 10-11psi i guess.

The conversion from 100mmHg (what the factory guage is in) to psi is times by 1.934. So +7 on the factory guage is 13.5psi.

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