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HOWTO: RB25DET High Boost mode with standard solenoid

paulr33

By paulr33,
in Tutorials / DIY / FAQ

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paulr33
paulr33

HOWTO: RB25DET High Boost mode with standard solenoid Intended Audience: Stock RB25DET owners Technical Level: Very Easy Duration: 5 minutes Effort: Easy Result: Fairly Good !!!Caution/Ach

Sciby
Sciby

Reset the computer by disconnecting the battery, put the brake pedal few times (to ensure there's no residual charge), then reconnect the battery. Good idea to take it for a good drive now, so it rema

Sklyn
Sklyn

Karu it doesn't matter because you won't use the solenoid at all once you install a boost controller. And with stock ecu and turbo do NOT run over 12 psi, naybe even 10 depending on your car.

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gotRICE? Veteran

gotRICE?

Posted
Posted
ah ok, i thought maybe the solenoid was to restrict it to 5 from 7. ah well there goes that idea. will keep shopping for a 10psi r32 one. Any diagrams going around to disconnect it once i get the 32 one?

I think i did one a few pages back :down:

Torques Mentor

Torques

Posted
Posted (edited)

Hi!

There is no restrictor as such.

The actuator is subdued to the manifold pressure unless the car reaches 4500 rpm or so.

At this point the solenoid kicks in and reduces the pressure on the actuator, tricking the actuator into 'assuming' the boost is lower than actually is.

The actuator is a 5PSI type ..

Cheers,

Andrew

ah ok, i thought maybe the solenoid was to restrict it to 5 from 7. ah well there goes that idea. will keep shopping for a 10psi r32 one. Any diagrams going around to disconnect it once i get the 32 one?
Edited by Torques
maddowse Proficient

maddowse

Posted
Posted
ah ok, i thought maybe the solenoid was to restrict it to 5 from 7. ah well there goes that idea. will keep shopping for a 10psi r32 one. Any diagrams going around to disconnect it once i get the 32 one?

once you have the 10psi actuator the solinoids will be obsolite wont they ??

  • 1 month later...
Tommy_J Contributor

Tommy_J

Posted
Posted
this mod has been around for a while now, how have peoples solenoids held up with being held open 100% of the time when it should normally be momentarily? any solenoid failures?

...I'll second that. Anyone?

  • 1 month later...
Bomba Contributor

Bomba

Posted
Posted

Attention R34 owners

I have just done this mod without cutting or stripping any wires and it works.

1) Unplug the solenoid

2) Feed wire through the ecu plug side and reconnect plug. (see pics on post 231 on pg12) ignore warning as he had a different problem (see post 355 pg18)

3) Turn ignition on but not engine

4) R34's have an earthing strap from the engine that earths on the chassis just below the solenoid via a spade plug. Attach other end of wire here.

5) You will here the solenoid 'click'.

6) Drive around on high boost below 4500 revs.

Took less time to perform the mod than it did to write this post :P

Side note for those who want a switch for fuel economy. There are 3 pedals in the drivers side foot well. The far right one is the fuel economy switch. It's a good switch as it's progressive and not just an on/off switch :P

Torques Mentor

Torques

Posted
Posted (edited)
could some one please send me a pic of how the vac hoses are ment to be connected to the solenoid because mine has been bypassed and i want to connect it back up.

Here you go ...

post-33912-1288562192_thumb.jpg

Edited by Torques
UWAM Contributor

UWAM

Posted
Posted

Anyone with an R34 that has done this and felt a difference, before you did the mod, did you see the boost change at 4500 rpm? Using the stock gauge, once I hit max boost around 2800, it doesn't change until the redline.

  • 1 month later...
  • 3 weeks later...
Shazza24 Proficient

Shazza24

Posted
Posted

Is this useless if you have an EBC?

Noobiest question Ive ever asked lol.

An EBC is basically a more advanced/adjustable version of the stock solenoid. Normally to fit a EBC the standard solenoid would be removed/disconnected.

Skavenski Collaborator

Skavenski

Posted
Posted

if you unplug one of the hoses and block it it tricks the solenoid into keeping the wastegate closed for longer coz its getting an inaccurate reading,

by doing this i am running 11psi and only takes 30 seconds to do. seems pretty safe and dont get any boost spikes as far as i can tell

cannabiscorpse Mentor

cannabiscorpse

Posted
Posted

if you unplug one of the hoses and block it it tricks the solenoid into keeping the wastegate closed for longer coz its getting an inaccurate reading,

by doing this i am running 11psi and only takes 30 seconds to do. seems pretty safe and dont get any boost spikes as far as i can tell

I had mine off and it definately did the same thing.. I ended up connecting it back up and doing it with the wire, but i am hitting 9 sometimes 10psi and i have only got a cat back and pod. Cant wait for my turbo back..

  • 2 weeks later...

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