Jump to content
SAU Community

N-1 vs std oil pump

The Alchemist
 Share

Recommended Posts

The Alchemist Collaborator

The Alchemist

Posted
Posted

got my N-1 oil pump yesterday and took it apart to compare to my std R32 GTR oil pump...(2 screws worked loose as they do )

here are the differences for interest sake:

1: the relief spring

std has a twin spring system N-1 has a single...both measured identical spring rates at 3 different heights starting from the installed height.

Interestingly the N-1 relief plunger has a small oil hole drilling about 8mm down from the top edge, level with the relief oil passage in the pump housing. This would have a dampening effect on the way the relief valve works as the spring cavity would have a head of oil in it that would have to squeeze out the small oil drilling first.

Plunger size was the same and relief valve cavity was the same.

2: the oil pump gears are where the biggest difference lies.

The N-1 inner gear has 1 less lobe (11) vs the std which has 12...this allows the internal volume of the pump gears to increase using a redesigned shape on the outer gear/inner gear meeting surfaces. We didn't CC the difference as the N-1 was obviously much larger than the Std R32 gear.

3: The gear hardness and material...

a hardness test was performed using a proper hardness tester in the machine shop. The std gears were a 0.56 and the N-1 scored a 0.96 a marked difference!

Also the gears were made out of the same material!! Sintered steel.

The major reason , I believe , that the N-1 gears have been hardened is that in order to increase the pumping volume the outer gear wall thickness has been dramatically reduced thus hardening is required to keep the strength up.

4:Internal channels are all larger in the pump housing and redesigned to increase flow

5: the pump backing plate has a redesigned screw fixing arrangment with an extra screw on the N-1 ( 8 screws vs 7 in the std ) Also the backing plate is 0.5mm thicker ( 6.5mm on the N-1 vs 6mm on the std )

A note worth noting :D the backing plate screws were not lock tighted, needless to say that they where during reassembly!!!

Cheers Mike

Link to comment
Share on other sites
RB26zcar Enthusiast

RB26zcar

Posted
Posted

Great info there mate...... It's good to see hard evidence of the N1 being a upgrade of the standard Nissan pump, after constaint reports of it being the same pump, with just a stiffer spring....

Link to comment
Share on other sites
GTRgeoff Grand Master

GTRgeoff

Posted
Posted

Good stuff. I had been led to believe the N1 was just a higher spring rate on the relief so it's good to see some testing.

What I have confirmed from FAST is that the RB25DET and RB26DETT oil pumps flow exactly the same amount, but it doesn't detail any defferences in construction, so to all intents it is the same pump. I can't recall if the part number was different.

Link to comment
Share on other sites
The Alchemist Collaborator

The Alchemist

Posted
  • Author
Posted

$850 NZ.

The Rb25 and the R32 GTR pump are indeed the same. We also happened to have one off a dead Rb25 and compared the two.

Interesting how the relief spring have the same spring rates eh?

Isn't the HKS pump worth a small fortune ??

Mike

Link to comment
Share on other sites
Gav Mentor

Gav

Posted
Posted

I picked up a used Trust pump for around the same price as an N1 and as GTS-t VSPEC says hopefully it is better than std.

Didn't happen to have a squizz at it when it went on did ya Paul?

Link to comment
Share on other sites
Cefiro_PWA Rising Star

Cefiro_PWA

Posted
Posted
Gav, As far as I'm aware both the Trust and HKS pumps have improved designs compared to the N1 pumps. I can take pics of my HKS pump as it's not on the engine yet, maybe someone will be able to see what differences there are.

please show us pics :P

Link to comment
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

    • Duncan
      Odometer LCD is Intermittently Wonky

      By Duncan · Posted

      Hi mate, I have never had an issue with the odometer in mine (450,000+ klm now) and can't remember another post about it. Still, your description of the likely cause sounds spot on, so an electrics repair is probably the next stop.
    • LjB123
      Custom Exhaust Questions - RB25DET Neo

      By LjB123 · Posted

      Cheers. I more want it quieter with the varex open. I only have the varex closed when i start up and roll out the driveway to keep everyone happy on days i take the car to work at 5 AM or come home late. So just a mod muffler will do tge trick? Something like that would require a retune hey?
    • joshuaho96
      My BMW 335i

      By joshuaho96 · Posted

      I was going to say generally speaking if it's like 80k+ miles since the valve cover has been replaced you don't even attempt to just replace the gasket. The valve cover itself will likely be warped and it will continue to leak after replacement, just not as severely. The valve cover PCV diaphragm can also tear and create a major vacuum leak. Welcome to BMW life. My friend's 2006 330i was t-boned and totaled out so he also just got a 335i so I can add to this thread now.
    • Kip
      Odometer LCD is Intermittently Wonky

      By Kip · Posted

      Hi all, For my '98 260rs... The odometer LCD occasionally turns blank or gives me only the bottom half or top half of the numbers. It's intermittent, which leaves me to believe it's a dead solder or loose wire somewhere. The odometer itself works. When the screen comes back, kms have been added to the trip and overall meters. A couple questions: Is this a known issue with the Stagea? I didn't see it pop up in my quick search, but that could be my searching skills. How accessible is the LCD screen in the cluster? I'm hoping it's a remove and replace type situation versus cracking open the whole housing. I'm hoping you all can narrow some of my initial troubleshooting. Any experience or opinions would be helpful.  
    • Kip
      C34 RSFour V Build in the US

      By Kip · Posted

      Yeah. Seeing the finish line must be quite the motivation. Good on you for sticking with it. Understood about the model choice. Also, totally get the challenge with sourcing parts. Based on your handle, I'm just a few hours south of you. All the little things I've bought so far come with $30 shipping, even if it's just stickers for the boot!
×
×
  • Create New...