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Cant Get Over 4psi On R33

rnbguy

By rnbguy,
in Engines & Forced Induction

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rnbguy Collaborator

rnbguy

Posted
Posted

hey guys,

ive just taken ownership of an r33 skyline , man you guys are lucky, there freakin fun to drive...

anyway thats not the reason of my post...

my question is, the turbo on this 1993 r33 gtst skyline wont go over 4psi... what could be causing it to limit?

From my previous experience boost limit can be caused by:

a) ecu limiting boost (but its only 4psi not the 12/14psi margin)

b) boost leak (will need to pressure test it)

c) exhaust leak in external wastegates however its an internal in this one

d) screwed turbo (hmmm?)

I dont mind if its any, as im confident with the help on these forums i can change it, can anyone think of another issue?

i notice a slight whislte noise when im driving but i dont think thats turbo related as it doesnt get louder, its more constant, and only happens when im moving (if it where turbo i think itll happen slightly while idle as its still spinning)

i just need a bit of your nissan experience on this kind of issue if possible.

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https://www.sau.com.au/forums/topic/254293-cant-get-over-4psi-on-r33/
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teng Rising Star

teng

Posted
Posted (edited)

I had the same problem. When i got my R33 it was only boosting at 0.4bar MAX. After numerous $$$$ and fiddling, i still couldn't find the problem. In the end i just bought a HKS Adjustable Actuator and adjusted it to 0.73bar and it fixed the problem permanently. I still don't know if it's a solenoid problem as i can't get my hands on a used one. The whining noise was even louder now than when it was in 0.4bar :)

Edited by teng
geraus Mentor

geraus

Posted
Posted

Hey mate, Try and get a manual boost tee and set it up to 8psi. it sounds like your solinoid isnt working properly. I;ve seen this happend before on my freinds car , when he unpluged his boost solinoid it melted and then we tried to fix the cable but didnt work.

cmoney Proficient

cmoney

Posted
Posted

+1 for the boost gauge you're reading this off.

Without any smoke from the exhaust, the turbo should probably not be stuffed. Just stick a proper dual stage (turbosmart or equivelant) unit in & set the boost to what you would like to run.

rnbguy Collaborator

rnbguy

Posted
  • Author
Posted

nah i have an after market ebay job gauge, im curious how the stock solinoid is connected , my assumption is the top hose goes out into the air intake system... the button hose sits between a boost source and the actuator correct?

does it matter with the top hose which point its supposed to plumb the air too (e.g. pre any sensors?)

QWK32 Veteran

QWK32

Posted
Posted
Most aftermarket boost gauges come in x1000kPa hence the stock will move and show the same pressure as the aftermarket one. I know mine does.

more like x100kPa (BAR). and unless you get an aftermarket gauge that reads in mmHg the stock gauge will read different to the aftermarket one.

also +7mmHg on the stock gauge is about 10psi.

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