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Stock Boost Not Going Above First Stage

Munkyb0y

By Munkyb0y,
in Engines & Forced Induction

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Munkyb0y Grand Master

Munkyb0y

Posted
Posted

Hey ppls.

R33, exhaust, pod. no other mods.

I noticed recently that the my stock boost doesnt seem to jump up a couple of psi after 4500rpm.

It used to go from 6-7psi (low) to 8-9psi (after~4.5k).

Today and yesterday i noticed it sitting on about 7psi the whole way to 6k.

Even though the car is warmed up and has done at least 2-3km by the time i tried this, is the ecu perhaps holding back till the car is alot warmer? could that be it?

Also, a while ago i tried the high boost mod, by earthing the solenoid. it freaked out, spiked to 14psi, still dunno why, but i'm sure it was all good after i put it back to standard. Could that be the cause.

Will a bleed valve set to desired boost (9psi) resolve this problem?

Any thoughts, or insight appreciated.

Links Veteran

Links

Posted
Posted (edited)

I'd say your solenoid isn't working correctly..

Hence it's sitting on 7psi.. and not 8/9psi..

Easier just to get a bleed valve for $30

ECU won't give a hoot whether your car is cold or warm.. it just triggers - >4,500 - open solenoid..

You can test it as I believe you should be able to trip it to open or close the solenoid if you do the "full boost" thing manually by grounding the wire.. see if you can hear it or try blowing air thruogh it..

Edited by Links
Munkyb0y Grand Master

Munkyb0y

Posted
  • Author
Posted
ECU won't give a hoot whether your car is cold or warm.. it just triggers - >4,500 - open solenoid..

You can test it as I believe you should be able to trip it to open or close the solenoid if you do the "full boost" thing manually by grounding the wire.. see if you can hear it or try blowing air thruogh it..

i will try that. cheers.

i thought the ecu did give a hoot. i think it's the same on the Z32 300's. i may be mistaken.

Munkyb0y Grand Master

Munkyb0y

Posted
  • Author
Posted
But the R33 stock solanoid only gives you 7psi above 4500.

5psi under that.

Anyway, definately get that manual one off the SAU guy. It's tops!

yeah i've already bought one, just got it, not fitted yet.

5psi then 7psi. but with exhaust and pod, turbo breathes better, and gains ~2psi on stock boost. hence 7 to 9.

Munkyb0y Grand Master

Munkyb0y

Posted
  • Author
Posted
You can test it as I believe you should be able to trip it to open or close the solenoid if you do the "full boost" thing manually by grounding the wire.. see if you can hear it or try blowing air thruogh it..

do i need the engine running to try this, or just ignition on?

will give it a shot tomoro.

Munkyb0y Grand Master

Munkyb0y

Posted
  • Author
Posted

i grounded the solenoid, and i can clearly hear it clicking. so i assume it must be working.

i've had no time, or space(traffic) to give it a decent run and check psi +2.

will let u know how it goes.

mad082 Grand Master

mad082

Posted
Posted

when i first got my car (it was stock as a rock) and it wouldn't go above 5psi.... for the first day or 2. then i read about the solenoid and i hooked it up to a battery (had a spare one, didnt do the highmode mod) just to see if it clicked over. it did then after that it would go straight to 7psi on the gauge, but it did feel like it got extra power at 4500rpm.

but i run one of the turbotech controllers. they are much better than the turbosmart one i have. it (the turbosmart) holds boost and keeps the wastegate open on gearchanges so when you grab the next gear the boost goes to 0 then slowly climbs. shocked me the first time i did it. boosted up 1st and then second and it worked fine, then grabbed 3rd and at 4000rpm i had just reached 0 boost.

Munkyb0y Grand Master

Munkyb0y

Posted
  • Author
Posted

ok, took it for a nice big run on the fwy tonight. reaching 9spi after 4500, no prob.

was very apparent in 2nd and 3rd, less so in 4th, but then i had to back off a bit at that stage, speed limits and all :D

so it looks like the solenoid is ok, maybe grounding it manually to get the thing to switch did the trick.

when i get time, i'll get the turbotech boost controller on and set to 9psi.

did u guys get better spool times, more response, etc etc, after installing the turbotech (compared to the standard solenoid)?

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