HOWTO: RB25DET High Boost mode with standard solenoid

[stefan-w]

Why does it work with you, but not with me?

Crap... beats me.

If it doesn't rain tomorrow, I'll pull out my soldering gun again.

Rain? Yeah, Dutch summer, woohooo

[Sparks]

lol @ not liking electrical tape but using it anyway!

Heatshrink is key. So long as you made sure it was long enough to properly cover the connection its all you need. And looks much neater.

Hahaha I just used the electrical tape to tidy the wires up, Not for the actual connections. Heatshrink is the best

[mosquitocoils]

Hi all, tried this on the weekend and it worked easy as pie. I cut the black wire and just ran a tiny piece of wire (about an inch long) to the screw that holds the solenoid bracket on. Just unscrewed/unbolted that one bolt, wrapped my wire around it once, then tightened it back up.

7 psi all the time now. Definately feels a lot free-er in the low end around 2500. But I have a slight dead spot now about 2100-2300... it's weird. It's definately an overall improvement though.

Here's a tip too: get some of that black 'cloth' tape and wrap both the original wire and the new wire you just ran to the bolt, in that tape. Makes it look as stock as anything!

[Shmee33]

hey i got a r33 and i think its a non turbo converted to turbo.

i dont have a boost solinoid but i got a boost controller which is hitting 10psi but it sits on 5 untill 4500???

how do i get full boost all the time.

thanks alex

[stefan-w]

Connected the solenoid to ground again yesterday, no luck even though I used another grounding point.

I'm not going to try again, just slap on an R32 actuator or EBC

[Randon_I_Am]

Done this in my 34 few weeks back, worked a treat. wired it up to a switch and LED in the dash.

[boiracer]

did this today, and wrapped my coils, gapped my plugs, drives like a different car.

i have a switch i was gonna install but after hard wireing it for testing. decided there is no need to turn it down again, boost can be right foot regulated, if you have a stock car and havent done it yet, do it now!!!!!!!!!!!

you wont be disapointed.

i actually used a male and female blade plug on each wire, so i can just plug it back in as normal if i need to for any reason

[stefan-w]

The solenoid is also some sort of a boost controller?

Stock, there is a hose from the intake tube going to the solenoid, and a T'd of hose from the hose between the actuator and intercooler pipe... I removed the piece of hosing from the T-piece, and attached the hose from the intake tube.

When it went to maximum boost, it had some misfiring, like in the coilpack thing.

But I fixed my coilpacks, it never misfires at max boost with the stock hoses... so I think it was 'over boosting'.

Am I right about my theory?

[Duncan]

spot on, the solenoid is a boost controller, or more correctly every boost controller uses a solenoid. The solenoid is just a big switch that turns on and off, when it is on it lets air out instead of sending it to the wastegate. WHen it's off the air goes to the wastegate, and when the wastegate sees more pressure than it's spring can handle it opens. they call it "duty cycle" for what percentage of the time its open eg50% duty cycle means 50% open, 50% closed

eg if you have 7psi spring and run the boost control solenoid at 50% you will run roughly 14psi at the motor - 50% of the 14psi goes to the wastegate and 50% gets bled off by the solenoid. That's just an example, the duty cycle settings aren't that easy, they normally need some trial and error.

jaycar have a fully adjustable boost controller that uses the standard solenoid

[stefan-w]

Now that's a good reply, thanks for the info!

[STYLN]

did the grounding trick last weekend and it's much better. But i crave more, so im thinking im going to install the turbosmart t valve i have at home this weekend and tune to 10-12 psi.

Thanks guys this was top mod!

[Keeffy]

Did this to mine to my s2 r33 the other day, set up a swithc in the engine bay stands out a bit though.

Feels fair bit more responsive too, not a bad little temp mod.

Cheers

[Birds]

WHY is your signature only showing the top half of miss Fox?

Does anyone know if the RB25DET retains two stages of boost when you fit a boost controller without doing this mod?

[AzN]

Boost mod works well for auto.

[33drifta]

WHY is your signature only showing the top half of miss Fox?

Does anyone know if the RB25DET retains two stages of boost when you fit a boost controller without doing this mod?

just click on the pick for the rest of her lol

[Newy]

sorry if im way off the mark, but can't you just run vac line from actuator to manifold pressure?(one of the nipples on ur intake piping) Wont this run actuator pressure? without the need of boost controller? Sorry if this is wrong, just seems easier to do to get 7psi across the rev range?

[Torques]

sorry if im way off the mark, but can't you just run vac line from actuator to manifold pressure?(one of the nipples on ur intake piping) Wont this run actuator pressure? without the need of boost controller? Sorry if this is wrong, just seems easier to do to get 7psi across the rev range?

Hello there!

Yes, I think in theory that would be working (connecting red and green in the picture),

however there might be some kind of calibrated bypass in the solenoid so not too much pressure is bled off the actuator.

See this picture: (red=compressed air, green=atmospheric/negative pressure)

Edited August 10, 2009 by Torques

[gotRICE?]

sorry if im way off the mark, but can't you just run vac line from actuator to manifold pressure?(one of the nipples on ur intake piping) Wont this run actuator pressure? without the need of boost controller? Sorry if this is wrong, just seems easier to do to get 7psi across the rev range?

You are correct, BUT the R33/34 Actuator is only set to 5psi, and the solenoid bleeds off an extra 2.

So running directly off the actuator would only net you 5psi. Hence why alot of people go for the R32 actuator upgrade. They run a 10psi actuator. Do away with the stock solenoid all together. Win win.

[Torques]

You are correct, BUT the R33/34 Actuator is only set to 5psi, and the solenoid bleeds off an extra 2.

So running directly off the actuator would only net you 5psi. Hence why alot of people go for the R32 actuator upgrade. They run a 10psi actuator. Do away with the stock solenoid all together. Win win.

I thought he meant bleeding the actuator line all the time ... but actually he didn't?

[Citizen]

I tried this today, opted to splice the ECU wire and earthed it on the pod filter bracket. Worked a treat, much more power in low-to-mid range with the extra boost, don't have to wait for 4500RPM to get a kick anymore! Got a boost controller on the way too but this will do temporarily