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Hi guys,

I have a R33 1996 GTST 4door sedan auto.

I have done a search and it seems that the standard boost for a R33 GTST is 7psi, but couldn't find any thread that matches and answers my querie.

Basically, my friend who drives a R34 GTT noticed that my standard boost guage is not reading above the half way marking being close to 7+mmhg? Which I believe is where it should read at max boost (i.e7psi).

I have a turbo back exhaust and big pod, would expect to be getting close to 8psi.

We disconnected the boost controller and still no difference? Is there something wrong with the boost control or is it the guage?

Any advice is much appreciated.

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what controller are you running, and also and yes 7psi after 4500rpm if you have stock controller or 4-5psi before 4500rpm and the gauge is reading right 7+mmhg=1.0bar which is 14.5psi so half gauge is right, the stock gauge may be not so acurate as compared to a hks but and also do you have any mods.

what controller are you running, and also and yes 7psi after 4500rpm if you have stock controller or 4-5psi before 4500rpm and the gauge is reading right 7+mmhg=1.0bar which is 14.5psi so half gauge is right, the stock gauge may be not so acurate as compared to a hks but and also do you have any mods.

It's stock a controller, and at max boost it's just below half way? Though it would be above, as friend's stock R34 GTT (with pod and cat back), at full boost is above half way mark. So R34 GTT's run higher stock boost??

Thanks.

Edited by godspd

Works like this.. from 0 - 4,500rpm - they run 4-5psi (depending on other factors) once it hits 4,500rpm the solenoid opens bleeding more air which will cause it to go to 7/8psi from there to redline.

mine - which is mainly stock did this but went to about 0.66Bar which is about 9psi so it can vary a little..

if it isn't going past the 1/2 way mark - check your going over 4,500rpm :(..

if your mates hits 8psi before that mark, he's probably got the boost solenoid out of the loop.

check under your bonnet and see if it's still hooked in and plugged in, it's on the right side under the stock air intake..

you could always get a turbotech boost controller and try using that instead..

Works like this.. from 0 - 4,500rpm - they run 4-5psi (depending on other factors) once it hits 4,500rpm the solenoid opens bleeding more air which will cause it to go to 7/8psi from there to redline.

mine - which is mainly stock did this but went to about 0.66Bar which is about 9psi so it can vary a little..

if it isn't going past the 1/2 way mark - check your going over 4,500rpm :D..

if your mates hits 8psi before that mark, he's probably got the boost solenoid out of the loop.

check under your bonnet and see if it's still hooked in and plugged in, it's on the right side under the stock air intake..

you could always get a turbotech boost controller and try using that instead..

Yes your absolutely right, it hits 7/8psi above 4500rpm due the opening of the solenoid (friend with the R34 knows this too) that's why he picked up that something might be wrong with my boost. The problem is that mine dosn't even do this at 7000rpm??? it just stays below the half way marking of the boost guage at full boost, which is telling me its around 5/6psi?? Something wrong here?

from the sounds of it you should possibly check the solenoid.. check the plumbing..

if the solenoid isn't opening about 4,500rpm you'll never get higher than 4-5psi..

It actually feels like, boost changes from around 3000rpm?? but not 4500rpm?

sooo..

It actually feels like, boost changes from around 3000rpm?? but not 4500rpm?

With a auto, you actually don't feel that big change in boost heheh, its quite progressive unfortunately...

huh?? I don't understand.. i'd be hell surprised if you can't notice a change by approx 30% in boost pressure.. you'll notice it whether it's auto or manual..

and the change at 3,000rpm.. that's not the solenoid.. the solenoid works from 4,500rpm.. not 2,000.. not 3,000..

We disconnected the boost controller and still no difference? Is there something wrong with the boost control or is it the guage?

what boost controller??

if you disconnected it without putting the solenoid back in the right way you will never get over 5psi..

did you plug it all back in with the T piece or did you just "take out the boost controller" ..

sorry.. just had to vent a little

edit: oh and one more thing, go and get a decent boost gauge..

Edited by Links
Hi guys,

I have a R33 1996 GTST 4door sedan auto.

I have done a search and it seems that the standard boost for a R33 GTST is 7psi, but couldn't find any thread that matches and answers my querie.

Basically, my friend who drives a R34 GTT noticed that my standard boost guage is not reading above the half way marking being close to 7+mmhg? Which I believe is where it should read at max boost (i.e7psi).

I have a turbo back exhaust and big pod, would expect to be getting close to 8psi.

We disconnected the boost controller and still no difference? Is there something wrong with the boost control or is it the guage?

Any advice is much appreciated.

the half way point on a standard gauge IS just over 7psi.

and if u're not running more than standard boost, it'll hit half way on the gauge mid way thru the rev range.

so it's running fine.

sooo..

It actually feels like, boost changes from around 3000rpm?? but not 4500rpm?

With a auto, you actually don't feel that big change in boost  heheh, its quite progressive unfortunately...

huh?? I don't understand.. i'd be hell surprised if you can't notice a change by approx 30% in boost pressure.. you'll notice it whether it's auto or manual..

and the change at 3,000rpm.. that's not the solenoid.. the solenoid works from 4,500rpm.. not 2,000.. not 3,000..

We disconnected the boost controller and still no difference? Is there something wrong with the boost control or is it the guage?

what boost controller??

if you disconnected it without putting the solenoid back in the right way you will never get over 5psi..

did you plug it all back in with the T piece or did you just "take out the boost controller" ..

sorry.. just had to vent a little

edit: oh and one more thing, go and get a decent boost gauge..

Its cool mate, we didn't take out the solenoid, just "unplugged the boost controller.

Plus what I am trying to say is that there is no jump in boost from 4500rpm, only which seems like to happen at around 3000rpm, but I could be wrong, as one can't look at the factory gauge on the dash while at the same time driving :)

hi mate,

just to let yo know that the stantard boost for the rb20det and the rb25det is

8 PSI as quoted in high performance imports magazine.....

hope it helps :)

Half right and half wrong.

The satndard boost for an RB25DET is 7/8 PSI

The standard boost for an RB20DET is 10 PSI

Just wanted to clarify this so no one3s gets confused.

The stock boost guage IS accurate. Your boost levels are fine, and for the record...the 34 guage reads in different measurement anyway.

Don't compare your guage to your friends 34 guage. Just take a reading...go to google and type in 'convert mm/hg to PSI'. Then work out your boost level from there. You will see that the stock guage is ok.

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