Jump to content
SAU Community

RB30 Q's

quincy777

By quincy777,
in Engines & Forced Induction

 Share

Recommended Posts

quincy777 Community Regular

quincy777

Posted
Posted

Hi all,

Couple of things to clarify about rb30/25 conversion.

I have read threw the sticky thread, and had some great imput from a couple of guys but need to clarify different answers as I have the block and head ready and waiting.

1. Using sk's 475 hp version of conversion. standard rb30 pistons with ceramic crowns I understand are not the weak point for this power, correct? Does this include boost of upto 20psi? If I have to have forged pistons to be safe - which ones to keep compression high?

2. If standard pistons are ok for above which rings to get?

3. GTR cams/springs, for this power do I need them? or will the rb25de ones be ok upto 250-300rwkw mark.

Thanks for your help guys, just didn't want to find out mistake or waste of money after I have finished.

Cheers

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/
Share on other sites
StockyMcStock Proficient

StockyMcStock

Posted
Posted

consider that with a properly sized turbo (GT35/40 1.06 rear for example) you will be hitting 450rwhp at about 15 psi, judging on what other people have got with decent tuning. the pistons will be fine unless it pings. in which case forgies will last about 2 seconds longer than cast pistons before destroying themselves. the rods are what you need to worry about. standard RB30 rods prepped (stress-relieved then shotpeened) will get you to about 300rwkw reliably, but i wouldn't push them to 7000rpm too regularly, know what i mean? :P

GTR springs could be worthwhile if you are using a DE head - apparently the seating pressure can be a bit iffy on them. or just get it checked by a head specialist and see what sort of pressure they're actually getting.

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1409395
Share on other sites
drunkenmaster Community Regular

drunkenmaster

Posted
Posted

I have just spent quite a bit of time going through the RB30 thread and also various websites and the pdf but one question which is brushed over but not directly addressed, well as far as I can see, is do all RB blocks share the same engine mount bolt pattern, that is, are all RB engine mounts fully interchangeable?

I thought I would post here rather than continue the cluttering of the RB30 thread.

Thanks guys

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1409420
Share on other sites
TTT Grand Master

TTT

Posted
Posted

1.) using SK's 475hp example, you will also have read his main key in that result.

I think it was something like... TUNING...TUNING...TUNING... and more TUNING...

Also, he got that 475HP at the engine using an old T04 of some sort at 1 bar boost. and at 6200rpm was max power.

the low RPM and low BOOST and careful tuning is the reason that engine has over 70,000kms on it and still going.

2.) I believe he used OEM rings, bearings and gaskets.

I think that CUBES PDF also has what part numbers and brands he used. The PDF is in his signature.

3.) Cams should be fine for that figure from other's finding. The Valve springs though... I'm not sure.

Joel (CUBES) and his mate both bought R32 RB25de heads and sent them away for testing.

Joels was fine but the other one had seating issues..

I think the GTR valves will set you back about 300 - 400 dollars and that would be fine for the power you are after.

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1409601
Share on other sites
Sydneykid Grand Master

Sydneykid

Posted
Posted
1.) using SK's 475hp example, you will also have read his main key in that result.

I think it was something like... TUNING...TUNING...TUNING... and more TUNING...

Also, he got that 475HP at the engine using an old T04 of some sort at 1 bar boost. and at 6200rpm was max power.

the low RPM and low BOOST and careful tuning is the reason that engine has over 70,000kms on it and still going.

2.) I believe he used OEM rings, bearings and gaskets.

I think that CUBES PDF also has what part numbers and brands he used. The PDF is in his signature.

3.) Cams should be fine for that figure from other's finding. The Valve springs though... I'm not sure.

Joel (CUBES) and his mate both bought R32 RB25de heads and sent them away for testing.

Joels was fine but the other one had seating issues..

I think the GTR valves will set you back about 300 - 400 dollars and that would be fine for the power you are after.

The engine has standard Commondoor everything, rings, bearings, seals the lot.

Yep the trick is low boost, low rpm, keep the power sensible (resist the urge for that extra 20 rwkw's) and TUNING.

It is not a simply swap to stick GTR (solid follower) valve springs in a GTST (hydraulic followers). You have to modify the spring seats and the retainers and set up the seat pressure with shims. That's why we went for 1 bar, the RB25DET springs handled it easily.

:D

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1409686
Share on other sites
quincy777 Community Regular

quincy777

Posted
  • Author
Posted
The engine has standard Commondoor everything, rings, bearings, seals the lot.

Yep the trick is low boost, low rpm, keep the power sensible (resist the urge for that extra 20 rwkw's) and TUNING.

It is not a simply swap to stick GTR (solid follower) valve springs in a GTST (hydraulic followers).  You have to modify the spring seats and the retainers and set up the seat pressure with shims.  That's why we went for 1 bar, the RB25DET springs handled it easily.

:)

Thanks for your help guys.

So keep to 1 bar of boost as max, don't rev beyond 6500 regardless of springs and all will be ok.

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1410204
Share on other sites
Bl4cK32 Grand Master

Bl4cK32

Posted
Posted
I have just spent quite a bit of time going through the RB30 thread and also various websites and the pdf but one question which is brushed over but not directly addressed, well as far as I can see, is do all RB blocks share the same engine mount bolt pattern, that is, are all RB engine mounts fully interchangeable?

I thought I would post here rather than continue the cluttering of the RB30 thread.

Thanks guys

The mounting points (bolt pattern) on the blocks are the same, but the actual engine mounts are different between all model rb's ive seen. Rb20 is different to rb25, is different to rb26, is different to rb30 ....

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1410315
Share on other sites
drunkenmaster Community Regular

drunkenmaster

Posted
Posted
The mounting points (bolt pattern) on the blocks are the same, but the actual engine mounts are different between all model rb's ive seen. Rb20 is different to rb25, is different to rb26, is different to rb30 ....

Appreciate it :kewl:

Link to comment
https://www.sau.com.au/forums/topic/76992-rb30-qs/#findComment-1413333
Share on other sites

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • 25zenki
      S1 rb25/s14 starting problem

      By 25zenki · Posted

      Harness is for a s1 Rb25det, and it is engine and lower harness.  the old harness had broken off plugs and was in very rough condition/exposed wires and splices etc. it is not able to be put back on the car, I could visually inspect to see if they had rewired any pins on the ecu plug. The fuel pump definitly isn’t turning off it’s an external pump and very loud you can hear it. Will look at the other harness tonight, am also going to pull the fuel rail and watch the injectors spray, will update here with what I find. Pretty sure at this point it has to be something to do with injectors because car will fire up on starting fluid and cas is clicking the Injectors. Fuel pressure is steady 43psi 
    • Waders360
      M35 Brake caliper replacement

      By Waders360 · Posted

      Sorry. Front brake calipers
    • MBS206
      S1 rb25/s14 starting problem

      By MBS206 · Posted

      Check the injectors flow evenly, and are actually flowing what you and the ECU think they should be flowing. If it's starting up on starter fluid, you have a fuel issue. Is it possible under cranking your fuel pump is turning off?   The harness you replaced, is that the whole engine harness? Do yourself a test, and drop the old harness on and plug it into the Z32 ECU. It's possible they've wired things different. From memory S1 to S2 is different in RB25 and you may have a wrong loom
    • 25zenki
      S1 rb25/s14 starting problem

      By 25zenki · Posted

      I haven’t pulled the injectors to watch them spray yet but they are clicking from the cas and all of the spark plugs are wet with fuel. I’ve thought the cylinders were being flooded from the beginning and was hoping fuel pressure would fix it. Tonight I am going to pull the rail and watch the injectors spray. Don’t know how to test/diagnose if the plugs are firing in correct sequence but that should be a timing thing and as far as timing goes my car still has the half moon for the cas can only install it 1 way. And my mechanical timing is 100% correct I posted photos above. Confirmed with the balancer on and off. 
    • 25zenki
      S1 rb25/s14 starting problem

      By 25zenki · Posted

      I checked spark on all cylinders and they all visually have spark with the plug pulled and grounded, but plug 1 is the only one that fouled. This was a running swap that blew up and was rebuilt by a machine shop, put a new wiring specialties harness and did all gaskets, studs, and bolts while it was out.  compression is 135-150 across all cylinders. Aside from that from my understanding with the z32 ecu and maf the car should start regardless. The wiring for TPS and the dual 02 sensor/ dual knock sensor stuff shouldn’t actually stop the car from starting or even running well, (just slightly rich)  they just give fault codes. Car supposedly is supposed to start as long as you have z32 afm and ecu with the nistune base map and that’s info coming from a well known and trusted tuner who does a lot with SR/RB (Rsenthalpy). After more trouble shooting today where I’m at right now is that the cas is sending signal to the injectors they click while spinning the rotor, Fuel pressure is now set at 43psi, all cylinders have good compression and all of the plugs looked great (just wet with fuel) except for cylinder 1 which was very black (cylinder 1 has 150psi compression). all of the coils generate spark if pulled out and grounded out on the head. On the fuel pump car just pops into the exhaust. On starting fluid car will fire off. Hard to tell if all cylinders are firing off but definitley a couple. sounds like all of them but it’s only for 3-5 seconds hard to tell. 
×
×
  • Create New...