Jump to content
SAU Community

Recommended Posts

hey guys just got my rb20 tuned and finished today, its didnt pull the power i wanted but i think this is due to lack of boost, i have high flowed turbs and all the supporting mods to run over 320rwhp, but when they went to tune it at 18psi, it would spike there then drop straight back to 12psi, wat is the deal there, there is no leaks in the cooler pipin anywhere as they thoroughly went over them, could this be the actuator on the turbo giving in, or would it be the stock bov opening up? how to i test these 2 things, any recommendations on wat it is would be greatly appreciated. So atm its tuned on 12psi.

Link to comment
https://www.sau.com.au/forums/topic/88513-just-dynoed-rb20det/
Share on other sites

thats the thing, they installed my apexi boost kit for the power fc, they said it wasnt working very well because it kept losing so much boost and couldnt hold it at 18psi at all, so i gave them my old manual boost controller, and they tuned it for 12psi and said that the manual one worked a bit better and wasnt so spiky, they still couldnt get it to stay at 18psi with the manual boost kit.

I found my stock actuator would drop back to 10-11psi at any boost above that.

An aftermarket adjustable would be well worth a look for 2 reasons: 1) you can set a higher base boost on the actuator and so are garanteed of that whatever your ebc does, and 2) The higher the base you set, the easier it will be for the ebc to do it's job and as a result you will have a more stable system with less spiking and a flat line to redline.

I also have a feeling the stock actuators aren't that good at holding anything above 10psi, unless combined with a decent EBC to pulse it.. Mine can sit on 13-14psi, but always dribbles back to 10-11psi in the higher rev range.

It may be one of those varying things - some factory ones may be fine, others get old and not so good.

I've got an RB20 and RB25 actuator sitting around, should do a couple of swaps and see which is better (onto rb25 turbo).

No.

Boost ramps up harder.

Try not to think about it too much. It works, that is why adjustable rods were created. :blink:

The RB25/VG30 actuator is quite soft and can be adjusted by hand, the RB20 on the other hand requires a big dirty screw driver to be levered against the elbow.

Edited by Cubes

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Which solenoid? Why was it changed? Again, why was this done? ...well, these wear..but ultimately, why was it changed? Did you reset the idle voltage level after fitment? I'm just a tad confused ~ the flash code doesn't allude to these items being faulty, so in my mind the only reason to change these things, would be some drive-ability issue....and if that's the case, what was the problem? Those questions aside, check if the dropping resistor is OK ...should be 11~14 ohms (TCU doesn't throw a flash code for this) ~ also, these TCU designs have full time power (to keep fault code RAM alive), and I think that'll throw a logic code (as opposed to the 10 hardware codes), if that power is missing (or the ram has gone bad in the TCU, which you can check..but that's another story here perhaps).
    • Question for people who "know stuff" I am looking at doing the new intake like the one in the picture (the pictured is designed for the OEM TB and intake plenum), this design has the filter behind the front bar, but, the filter sits where the OEM duct heads into the front bar, and the standard aperture when the OEM ducting is removed allows the filter to pulled back out of the front bar into the engine bay for servicing, a simple blanking plate is used to seal the aperture behind the filter This will require a 45° silicone hose from the TB, like the alloy pipe that is currently there, to another 45° silicone hose to get a straight run to the aperture in the front bar Question: how will it effect the tune if I move the MAF about 100-150mm forward, the red is around where my MAF is currently, and the green would be where it would end up Like this This is the hole the filter goes through  Ends up like this LOL..Cheers    
    • Despite the level up question, actually I do know what that is....it is a pressure sender wire.  So check out around the oil filter for an oil pressure sender, or maybe fuel pressure near the filter or on the engine. Possibly but less likely coolant pressure sensor because they tend to be combined temp/pressure senders if you have one. Could also be brake pressure (in a brake line somewhere pre ABS) but maybe I'm the only one that has that on a skyline.
    • Pull codes via the self-diagnosis procedure. As far as I can tell this is just a sign of transmission issues but not a code unto itself.
    • Hi All, putting the engine back together and everything is perfect except have this plug left over.. any ideas what it is for and where it goes? Is on cold side under the intake plenum *note not a stock plug, as everything has been modified Cheers
×
×
  • Create New...