Oil Pressure Issue? And 2 Stage Boost Issue (rb25 R32)

[GTSTLOVE]

So, ive had a catch can installed on my car for a few months, and it feels like my oil pressure is too high. I did a oil flush when i installed the can as well, 5w40 (maybe thats the cause?). If it isnt the oil thats causing high oil pressure, im thinking maybe the can setup?. Its non atmospheric, 1 way valve still connected to plenum, and plumbed from exhaust side to can, can baffled with loose steel wool, and plumbed back into intake before turbo. before putting on the can and oil change, at idle it would sit at between 1-2 (on the stock oil pres gauge), but now it sits at 4, and at pre 4500 rpm boost, its at like 5-7 on stock gauge. it seems way too high than before.

And for the second issue, the 2 stage boost is still active, its a jdm rb25 swap with what appears to be using the rb20 harness. According to the R33's, the ground for the boost solenoid needs to be grounded to the body, but since i don't have the rb25 harness looms im guessing the ecu is acting like its still an rb20. the wastegate is directly connected to the i/c pipe but it still stays at 3-5 psi until 4500 rpm then it gets to 7 psi. How can i disable the rb20's 2 stage boost? or is it not possible with rb25 turbo?

[Leroy Peterson]

what sort of oil pressures are you getting?

have you tried venting the catch can to atmos and see if theres a difference?

if stage 2 is too high just install a stage 1.

[GTSTLOVE]

what sort of oil pressures are you getting?

have you tried venting the catch can to atmos and see if theres a difference?

if stage 2 is too high just install a stage 1.

Im going by the stock oil press gauge on the dash, but it goes from 1-8 increments. im seeing idle pressure of "4" and WOT 6-7 almost max. Before it used to idle low psi at like 1-2. Sorry im not familiar with the measurements that the dash reads at i wish i could give more accurate numbers. I believe 6 on the gauge is 75 psi. and 4 on the gauge is 56 psi.

and i want the 2 stage boost removed, so i get max stock psi at low rpms instead of only at 4500+

[GTSTLOVE]

so yeah, majority of the time my idle pressure is 50-60 psi. thats way over the normal threshold. would 5w40 be too thin or thick? or is my crank case not venting enough pressure. it ran the same psi when i had the can running atmospherically

[89CAL]

I see anywhere from 20-30psi at idle running 10w40 and with a Nismo oil pump and restrictors fitted. I cant really see how a catch can would worry it but seen as its the last thing you have done wouldn't it make sense to vent the catch while its idling and see what happens to oil pressure? How is the catch can set up anyway?

What state is the oil filter in? Trying to think of things that would cause an issue if all you have done is add a catch can. Do you have an oil cooler fitted?

[KiwiRS4T]

If your wastegate is plumbed directly to the intercooler pipe you don't have a 2 stage boost and your solenoid is doing nothing (presumably its not connected to anything). If you want more boost get an RB20 actuator which should give you around 10 psi.

I don't see how your catch can has anything to do with your oil pressure.

5W40 is not too thick.

[GTSTLOVE]

I re routed the pcv lines back to a stock setup and it seems a little better now. i had the can plumbed in properly considering i researched it for days to be sure. i think one of my pcv hoses may have not been strong enough and collapsed under vacuum

And even though i have the WG connected directly to the i/c pipe it still has 2 stage. i dont feel 7+psi until 4500 rpm exactly which is the stock rb setup, but R32s didnt have a boost solenoid. so im guessing either the wastegate has its own way of increasing boost, like dual spring or something like that. I feel like theres a wire that should be coming from the ECU to what should be the rb25s solenoid, but as stated before since the R32s never had a solenoid, and i have a Mines refurbished ecu for the engine swap something mustve been left out. If anyone knows the wire number for the solenoid i want to trace the wire if there even is one.

Unless some rb20 Gtsts had a boost solenoid? However i dont see the plug that would've connected to it. I'm so confused

Edited May 26, 2016 by GTSTLOVE

[Ben C34]

No way can a wastegate on its own have a 2 stage setup.

The mines ecu would be doing you no good. Put it in the bin and get a proper ecu for it before you kill the engine.

The car could be very lean, or rich, or have too much or not enough timing causing the issue you describe.

[KiwiRS4T]

I'm so confused

This