Car Not Boosting Past 0.6bar...help

[flyz33]

hey guys,

I have abit of an issue with my car (r34 gtr) at the moment and just wondering if you guys might be able to lend a hand and give me some ideas on what the issue could be. Installed a pair of HKS2530's that I purchased from a forumer not long ago. Put the car on the dyno for a tune last weekend and the car wouldnt boost over 0.6Bar. We took off the waste gate vacuum line to test the boost but still, it would not go over 0.6Bar.

I did a quick search on here and seems the usual troubleshoots are to check the lines and cooler piping. I went and got a 'smoke test' done on the car to see if there was a leak and where it could be coming from. There was no leak.

Im abit stumped as to what it could be...could cam timing cause this boost issue?

Cheers

[Johnny]

Hey man, i had a similar issue with mine; on the dyno getting tuned with a newly installed evc it wouldnt boost past 0.5-0.6 bar. At first they checked vacumn lines n found nothing so we thought it was an issue with actuators or the boost controller but after careful check it turned out to be a vacumn line, not sure which one but it gave rob from creatd ms a headache for a couple of hours.

I remember vaguely somewhere under the plenum???

hope you sort it out mate, good luck!

[flyz33]

Hey man, i had a similar issue with mine; on the dyno getting tuned with a newly installed evc it wouldnt boost past 0.5-0.6 bar. At first they checked vacumn lines n found nothing so we thought it was an issue with actuators or the boost controller but after careful check it turned out to be a vacumn line, not sure which one but it gave rob from creatd ms a headache for a couple of hours.

I remember vaguely somewhere under the plenum???

hope you sort it out mate, good luck!

thanks for the reply man. I will probably be changing out the vacuum lines just for good measure. Hopefully that fixes things. Although, it should have boosted as we took out the wastegate vacuum line? did your mechanic try that when you had your problem?

[Johnny]

thanks for the reply man. I will probably be changing out the vacuum lines just for good measure. Hopefully that fixes things. Although, it should have boosted as we took out the wastegate vacuum line? did your mechanic try that when you had your problem?

Hey man, npz i jst hope you get it sorted so you can enjoy your car.

we didnt try anything with the gates as that could be quite dangerous, found the problem beofre anything like that had to be attempted. Could it be the turbos? are they new?

maybe check to see if the installation was done right, gaskets etc or maybe its the intake rubber pipes sucking shut when it reaches 0.5bar

i dunno just throwing ideas around now cos i have no idea

goodluck bro, keep us updated

[BK]

I had similar problem with hks gt-ss turbos not boosting up, no matter how much I tried winding into them. Same thing with disconnecting actuator lines. Turned out to be collapsed cat converter - the more the car revved, the more backpressure was created so no extra boost. Drop the exhaust at y pipe and see what happens before you go any further. It's turned me off running cats ever again after that.

[flyz33]

I had similar problem with hks gt-ss turbos not boosting up, no matter how much I tried winding into them. Same thing with disconnecting actuator lines. Turned out to be collapsed cat converter - the more the car revved, the more backpressure was created so no extra boost. Drop the exhaust at y pipe and see what happens before you go any further. It's turned me off running cats ever again after that.

I have actually de-catted my cat (looks like a compliance cat), to prevent that from happening.

definately frustrating as I cant wait to wake up these turbos.

[flyz33]

update:

still havnt figured out what wrong with it yet.

Pulled off the cam gear cover and found that the car came with Tomei Adjustable cam gears....which brings me to my question. Can cam timing affect boost? As i suspect the timing is off.

Cheers