Jump to content
SAU Community

Recommended Posts

Narrow it down to ill be setting pressure to 70-65psi

Narrow the restritors to

Leave VCt, 1.3mm in the other two

Or

Leave VCt, 1.5mm and block rear, (or should this be block middle 1.5mm rear)

Abr33 are you running a head drain? Also are you running bigger sump with extended pickup?

Doesnt really matter which oil feed gets blocked, it all runs a common gallery for lifters...

I have a gated and baffled sump that I made with better pickup, holds bit over 7 litres. If you need pics I think I put them up several pages back or can send more.

And have a rear head drain/vent also enlarged oil return channels and drilled return holes to 9mm. Also running front of sump to cam vent but will send it to a can soon.

Don't block the rear oil feed it does matter, block the centre at 75 to 85 psi max hot oil pressure if you leave the front restrictor std (which if you want the VCt to operate you should) and block the centre then reducing the rear to as little as 0.9mm combined with using a high volume pump so as oil pressure at idle is 30 psi or greater hot the lifters won't rattle.

Don't block the rear oil feed it does matter, block the centre at 75 to 85 psi max hot oil pressure if you leave the front restrictor std (which if you want the VCt to operate you should) and block the centre then reducing the rear to as little as 0.9mm combined with using a high volume pump so as oil pressure at idle is 30 psi or greater hot the lifters won't rattle.

So many mixed story's, this thread has a graph on the first page and that says to block the rear?

Fine on a gtr head with solid lifters and no VCt. You have VCt and hydraulic lifters yes? Then don't block the rear, your engine builder would know this if they don't be concerned, mention loss over distance and gauge the response , trust me block the rear and the lifters at the rear of the head will define it for you.

Fine on a gtr head with solid lifters and no VCt. You have VCt and hydraulic lifters yes? Then don't block the rear, your engine builder would know this if they don't be concerned, mention loss over distance and gauge the response , trust me block the rear and the lifters at the rear of the head will define it for you.

Yeah running hydraulic lifters and VCt, the engine builder didn't wanna put any in for the fact of noisey lifters...

Nitto website says dual spring crack off is 120psi... Single spring crack off is 75psi??

Should I do the single spring to give me the 75psi if this is max?

  • 2 weeks later...

Hello all.

I've searched but havent found the answer I'm looking for....

My motor is a Stock S2 RB25DET, standard bottom end and oil pump. But has Tomei Poncams and Hi flow OP6 turbo.

Its only street driven but with occasional drags.

What restrictors should I fit.

SK has said Leave VCT, block center and 1.5mm for rear.

From my searching I have found that the standard RB25DET restrictors are already 1.5mm. So all I need to do is block the center one?

Or is there no point in even removing the head to just to block off one restrictor with a stock motor?

Cheers

I am getting a bit of oil through my cooler piping etc as its running the stock breather hoses off the rocker covers.

Will look at a catch can.

Btw motor is out of the car at the moment, hence why I'm thinking of pulling the head to do the restrictors...

  • 1 month later...

Hi everyone my name is stef..I hope someone can offer me some advice as I have read this hole thread from start to finish!

I'm in the middle of a forged rb25det build with an n1 oil pump.. After reading this thread I have come to the conclusion that I need to leave the vvt, block the middle and restrict the rear to 1.5mm. Now upon stripping the engine which I believe has been untouched I have found that all three restrictor a are 1.2mm which has now confused me lol..should I still block the middle supply and drill the rear out to 1.5mm? Thanks for any help

Regards

Stef

Yeah I just got the head off mine this week. The front vct is 1.5mm and the other 2 are 1.2mm

Motor is a S2 RB25DET from a 95 R33.

So should I just put in 2x 1mm?

Depends on what pump you are using. I have an N1 pump RB30 block S2 head and I'm successfully using 2 x 1mm restrictors (street. track and to come - drags).

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

    • Nope.    Grab a varex and turn it down as you get close to home, win win? 
    • So, I've had my V36 for about a month now and have already copped an "excessive exhaust noise" notification from QLD TMR, reported by someone in my local area. It's a twin as per the original, and can have a bit of a throaty note to it when idling cold 😄 and if I do get up it a bit, it can be noisy, but it did pass a roadworthy inspection before sale, so.... ... but in the interest of being a good neighbour, I do want to quieten it down a bit. Is anyone here running a quiet aftermarket cat-back on their V36 or 370Z? And the big, bold question: does an aftermarket cat-back really make much of a performance difference on these cars?
    • The wiring diagram for the R33 RB25 is freely available, and is essentially the same same as most other RBs (just with differences as to which pin # does which job). To get the ECU to power up, you just need to provide power to the ECCS relay, and have the other power feeds that come in from the top left of the wiring diagram (wrt the ECU) that give perma power to the fuel pump relay, the ECU itself, etc etc, all connected. When you put power on all these it will just come to life. It's pretty clear from the diagram what needs to happen. Just follow the lines from the 12V + supply stuff in the top left over towards the ECU. I've even posted snips of such diagrams (not for vanilla 25, I think for Neo and 26) to various threads here in the last few months, talking about what it takes to get the fuel pump and FPCM up and going. Search these up and they will help get you started on doing the same with the vanilla 25 diagram. Hell, for all I know, I've done the same with that one in years past and have forgotten.
    • Yep...so unless someone posts up the answer you will need to probe from the ECU connector to the dash plug with a multi meter in continuity mode to trace the wires.  Note the ECU has multiple - and + (and across different key settings - Battery, IGN and Start) and most likely the power is fed from the connector(s) that is normally near the left hand headlight.
    • Thanks Duncan, I am actually just trying to get the Rb turning and running with the RB25DET S2 original loom itself  I am just trying to get it going outside the body and not thinking about the S15 or trying to match anything to the S15 loom at all I am only trying to see if anyone has done this and what pin they found to be the ignition trigger and ECU+/- on the dash connector, that's about it. Thanks  
×
×
  • Create New...