Jump to content
SAU Community

RB25DET Series 1 & Series 2 Gearbox Identification

Ratsun
 Share

Recommended Posts

BK Grand Master

BK

Posted
Posted

You can't know unless you're familiar with the transmissions once disassembled. Coming from GTR boxes (which are the same as R33 Gts turbos Gearset and synchro wise), the only difference will come with the synchros, shift fork and gear with 3rd like 97+ stuff which translates to any FS5R30A transmission. Not sure which years are series 1 and 2 you're referring to in R33 gts,t. In GTR, 89 - 96 is same, 97 -98 upgraded (R33 GTR series 3), but not much of an upgrade really like people make out but are not interchangeable. Old mate Hardsteppa just went through this on a non GTR on this page.

hardsteppa Grand Master

hardsteppa

Posted
Posted

I did indeed. I would say its unlikely you have a series 2 box, as i gather the vast majority are series 1. As above you would need to pull it apart and look at 3rd to see for sure.

hardsteppa Grand Master

hardsteppa

Posted
Posted

clip.JPG.792cafd97fd334f9a8172a93bf905ce6.JPG

 

this bit circled. So you are extremely unlikely to find a brand new 3rd gear, 4th gear,  2>3 coupler or synchro hub, but should be able to find everything else new. 

Ratsun Rookie

Ratsun

Posted
  • Author
Posted

@hardsteppa thanks heaps

It appears that I have the following options, any advice would be a appreciated

a) rebuild the series 1

b) source a series 2

c) transplant the internals from GTR

The box is being mated to a mildly worked RB26 and then shoe-horned into a 240z street/track car, so its going to get a bit of a hard life and therefore needs to be somewhat reliable.

hardsteppa Grand Master

hardsteppa

Posted
Posted

Around 3g aus i believe. Between buying a box and buying parts for rebuild i spent over 2g, and still have all old gears, beat up casing etc. So all brand new for that price is worthwhile IMO.

  • Like 1
admS15 Grand Master

admS15

Posted
Posted

I bought a brand new r34gtt box for 3k at the end of last year when there was heaps of stock. Price rose a bit in the next few months. I have been told recently they are now made to order and it's around a 3 month wait. 

  • 5 years later...
hardsteppa Grand Master

hardsteppa

Posted
Posted
On 19/12/2019 at 10:55 PM, GTSBoy said:

Let's just suggest that the differences are insignificant. Just because it has a different part number doesn't mean it's functionally different.

If you call a completely different improved 2nd>3rd  synchro setup insignificant then, ...yes.

Just finalising an R34 RB25 gearbox swap into R33, couple of things to note.  If you are going with a push-clutch rather than the R34's pull, there are bosses moulded into the bellhousing you need to drill and tap to be able to bolt your clutch slave cylinder on. I put a stud into the hole closest to the clutch fork to make installing the slave easier, but up to you.

You need to change the front cover plate....obviously, as it's well-covered everywhere. If you were short of $$ looks like you could adapt the R34 front cover to be able to take the clutch fork ballstud/pivot bolt but, up to you, prob not worth it.

The neutral and reverse plugs on the sensors that the box comes with are likely to be different. You can get the loom side of the connectors here, and they are EXCELLENT quality.

https://www.efisolutions.com.au/2-pin-grey-connector-nissan-reverse-switch-fuel-ha

https://www.efisolutions.com.au/2-pin-black-connector-fits-some-nissan-neutral-swi~138383

The box comes filled with oil but it is a corrosion-protection oil only, do not run the box with it. Drain and refill with a good 75w-90 once box is installed.

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

    • Kapr
      RB20DE NEO smallbox clutch.

      By Kapr · Posted

      For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
×
×
  • Create New...