Jump to content
SAU Community

Recommended Posts

Hello. Was wondering if the RB25 crank shafts were same/similar across the range? What are the differences? 
 

I couldn’t find a definitive answer, and have a Neo series motor and needed a new crank. I can find plenty for sale but obviously want to make sure there isnt any difference between one from say an R33, and my current one

 

Also out of curiosity, is there a difference between the RB25DET blocks themselves from an R34 and R33?

Link to comment
https://www.sau.com.au/forums/topic/485981-rb25-crankshaft-differences/
Share on other sites

They're all essentially the same**. Although you have to differentiate between "block" and "bottom end", because Neos have different pistons and rods to vanilla 25s.

I won't speak to whether there were oil pump drive changes to take into consideration, as that can be fixed anyway.

6 hours ago, GTSBoy said:

They're all essentially the same**. Although you have to differentiate between "block" and "bottom end", because Neos have different pistons and rods to vanilla 25s.

I won't speak to whether there were oil pump drive changes to take into consideration, as that can be fixed anyway.

Thanks heaps. So basically, bare block, very very similar. And cranks are the same

12 hours ago, GTSBoy said:

won't speak to whether there were oil pump drive changes to take into consideration

Both NEOs I bought had short oil pump drives on them, even though internet legend has it they introduced longer collars on them.

However, it's true NEO motors used N1 sized oil pump gears and not the same ones found in the R33 RB25 motor.

Block wise, NEO has the front head VCT drained blocked off, but you can easily remove that.

22 minutes ago, Dose Pipe Sutututu said:

Both NEOs I bought had short oil pump drives on them, even though internet legend has it they introduced longer collars on them.

However, it's true NEO motors used N1 sized oil pump gears and not the same ones found in the R33 RB25 motor.

Block wise, NEO has the front head VCT drained blocked off, but you can easily remove that.

Thanks. So crank is the same, stroke and everything is the same? Im getting crank collar installed anyway

 

I have heard this internet myth as well, but ive had a few unopened Neos as well and no long nose crank. Supposedly it may have been a series 2 thing? The ones I had were from series 1’s. No idea haha

19 minutes ago, LjB123 said:

Thanks. So crank is the same, stroke and everything is the same? Im getting crank collar installed anyway

Correct :)

And whatever you do, don't use an oil pump gear, especially the one that starts with the same letter as Santa and the last letter ends with the same first letter as Lagoon. Get a proper oil pump, like a Nitto, Tomei, etc. and make sure you invest in a big fk off sump.

Won't go into too much detail, but I am sure it caused my previous built motor to go bang.

39 minutes ago, Dose Pipe Sutututu said:

Correct :)

And whatever you do, don't use an oil pump gear, especially the one that starts with the same letter as Santa and the last letter ends with the same first letter as Lagoon. Get a proper oil pump, like a Nitto, Tomei, etc. and make sure you invest in a big fk off sump.

Won't go into too much detail, but I am sure it caused my previous built motor to go bang.

No issues here with my PRP gears in an OEM pump housing. I did confirm all housing clearances were to spec prior though. Cheers. 

  • Like 1
On 11/12/2024 at 11:42 AM, Dose Pipe Sutututu said:

Correct :)

And whatever you do, don't use an oil pump gear, especially the one that starts with the same letter as Santa and the last letter ends with the same first letter as Lagoon. Get a proper oil pump, like a Nitto, Tomei, etc. and make sure you invest in a big fk off sump.

Won't go into too much detail, but I am sure it caused my previous built motor to go bang.

Well my freshly rebuilt RB25DET Neo went bang 1000kms in, completely fried big end bearing in cylinder 1 so bad my engine seized. No knocking or oil pressure issue prior to this happening, all happened within less than a second. Had Nitto oil pump, 8L baffled sump, head drain, oil restrictors, the lot put in to prevent me spinning a bearing like i did to need the rebuild. Mechanic that looked after the works has no idea what caused it. Reckoned it may have been bearing clearance wrong in cylinder 1 we have no idea. Machinist who did the work reckoned it was something on the mechanic. Anyway thats between them, i had no part in it, just paid the money

Curiosity question, does the oil system on RB’s go

sump > oil pump > filter > around engine?

If so, if you had a leak on an oil filter relocation plate, say

sump > oil pump > filter > LEAK > around engine

would this cause a low oil pressure reading if the sensors was before the filter?

 

TIA

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

    • I would just put EBC back on the "I would not use their stuff" pile and move on.
    • Can I suggest you try EBC directly again and link them to as many competitor catalogues as you can to show their listing is incorrect, eg https://dba.com.au/product/front-4000-series-hd-brake-rotor-dba42304/ If you have access to an R33 GTST VIN and your VIN, you could also use a Nissan Parts lookup like Amayama to show them the part number is different between 33 GTST and 34 GTT which may get their attention
    • So i got reply from EBC and they just this site where you can clearly see those 296mm fronts on R34 GTT. I send them photos and "quotes" that 296mm are not for 34 GTT and they are too small. But it will be very hard to return them cuz nobody here knows 100% and they just copy those EBC catalogue :-D https://ebcbrakesdirect.com/automotive/nissan/skyline-r34
    • Hi, is the HKS  Tower Bar still available ? negotiable ? 🤔
    • From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
×
×
  • Create New...