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Evening fellow car lovers...

My car - R33 GTST

Recently i did the following modifications... upgraded to R34 GTT intercooler, installed Turbo Smart Dual Stage Boost Controller (switch mounted in cabin to switch between a high and low boost setting) and a Drift Boost Guage. Installed everything myself...

Now... with the boost controller at its minimal settings (as low as the dials can go), im getting 2 different boost readings between the factory guage and the aftermarket one. I installed the aftermarket one onto the thicker hose commin off the intake manifold goin to the fuel pressure regulator (so the guages are taking readins of opposite sides of the intake manifold).

Stock guage is telling me about 8-9 psi... aftermarket guage is telling me 0.75 bar... thats like near 11psi??

Why/Which is correct??? :down: lol in oversight whats the point of having a dual stage boost controller if at its low boost setting its already at the limit of the factory turbo :D (i wasnt planin on upgradin the turbo)

Any input would be greatly appreciated :)

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Firstly, a gauge is only as good as the manufacturer. It's not beyond the realms of possibility for 2 different gauges to give 2 different readings of the same thing. The Nissan factory gauges are notoriously inaccurate, though.

And a boost controller cannot lower the boost below standard. It can only raise boost above standard.

Firstly, a gauge is only as good as the manufacturer. It's not beyond the realms of possibility for 2 different gauges to give 2 different readings of the same thing. The Nissan factory gauges are notoriously inaccurate, though.

And a boost controller cannot lower the boost below standard. It can only raise boost above standard.

Like the man says, if you are concerned get your aftermarket boost gauge calibrated.

Cheers GW

The aftermarket boost controller, should be able to get boost BELOW 7PSi, if installed correctly.

The factory actuator is only a 3PSi setup.

The question is, did you remove the factory solenoid?

Also, have you removed the ball and spring from the Turbo Smart tee-piece?

Those boost controllers aren't that great... I ran one, switched for the little $20 boost controller and haven't looked back!

The aftermarket boost controller, should be able to get boost BELOW 7PSi, if installed correctly.

The factory actuator is only a 3PSi setup.

The question is, did you remove the factory solenoid?

Also, have you removed the ball and spring from the Turbo Smart tee-piece?

Those boost controllers aren't that great... I ran one, switched for the little $20 boost controller and haven't looked back!

Uhhh no Im pretty sure the stock R33 GTST actuator is set at 7psi...

Have you ever actually seen a 33 hold 3psi on a stock turbo with everything functioning correctly?

I did remove the factory boost solenoid... and what spring inside tpeice???? lol i just hooked the tpeice between the turbo nd wastegate like the instructions said and blocked off the other top hose which went to the factory boost solenoid... nd yeah at its minimal settings its at like .75 bar lol

What sort of things would i need to check to see if anythin went wrong in installation?? Im pretty sure i did everything correctly though cause it all works lol

Uhhh no Im pretty sure the stock R33 GTST actuator is set at 7psi...

Have you ever actually seen a 33 hold 3psi on a stock turbo with everything functioning correctly?

Yeah the stock actuator is two stage. 5psi to 5000rpm then 7psi to redline :thumbsup:

I take it that your Drift boost gauge just a cheap knock off, in which case its properly as useless as the stock one. Go out and get a proper brand gauge, personally i wouldnt use any thing less than autometer (not autogague) so that means around the 100-150mark depending where you get it from, if you want to spend more on apexi and the like thats all good, you'll probably get an even more accurate reading but in your case an autometer should serve you well.

If you have the basic breathing mods done, ie fmic, turboback exhaust and filter than on low boost with no solinod you should be around the 6-7psi mark.

The location on the manifold where you get your vacuum/boost reading doesnt matter as long as its definately a manifold feed.

LOL, where do you go about getting boost guages caliibrated?

Nearly missed this, first off gauge needs to be cabable of being opened without terminal damage being inflicted. (best option) if not can get correction chart? The yellow pages is always a good place to start, mechanical gauge range = press - 0 - vacuum, electrical = take sensor also. Any NATA instro calibration company or connections to airforce/airlines/altimeter calibration joints, know anyone in the sky-diving game.......breathing? :thumbsup:

Cheers GW

Heya, i dont think the drift guage is faulty, it sells for 90 bux... nd is pretty lol...

I havent done air intake or exhaust mods yet... pod filter is on its way from ebay :banana: nd exhuast wont be for a while. Ahwell i dont really need the turbo to boost more than it is at the moment anyway lol, after i get the exhaust and a safc ill get tuned on a dyno and they can look at it then :down:

thanx for input guys

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