Jump to content
SAU Community

Recommended Posts

  • 12 years later...
On 17/07/2021 at 5:52 AM, schowdhry said:

hello from the year 2021 blind elk if your still on here i need your help! i have just swapped the rb25 neo into my gts4, all the mechanical work is done but i need help with wiring up the ecu! 

@blind_elk

  • 7 months later...
On 17/07/2021 at 6:22 AM, schowdhry said:

hello from the year 2021 blind elk if your still on here i need your help! i have just swapped the rb25 neo into my gts4, all the mechanical work is done but i need help with wiring up the ecu! 

Are you available to chat with about this conversion ??

  • 2 months later...
On 11/16/2008 at 3:16 PM, blind_elk said:

Sorry, but that's rubbish. When I did the swap in mine, it all just swapped over.

This is Rubbish information and basically screwed up my build plans. 

 

RB25DET (Neo) does not use the same AWD oil pan as the RB20.  The Pan's do not swap. Bolt holes are not aligned. I'll have more photos when I pick it up from the shop. 

 

So to be specific as possible, since every thread I find about this information is vague and useless. 

 

 

1989 GTS-4 Coupe - AWD - Turbo RB20DET 5spd Manual. 

Engine  - RB25DET NEO - Stagea - most likely automatic car. 

 

Car in Question 

 

IMG_20210510_152439.thumb.jpg.067204d9eb6cb415c07435d06db840f1.jpg

 

Engine

IMG_20210429_122841.thumb.jpg.d39938a742f75efc3df061314ffa2659.jpg

RB25DET NEO AWD PAN

20220518_171456.thumb.jpg.73818ee2fb8d51101fa0f6d4a6ab45e7.jpg

RB20DET AWD PAN

20220518_171538.thumb.jpg.291f0f04d4d14ad2c6cf598be6b25d78.jpg

On 7/16/2021 at 1:22 PM, schowdhry said:

hello from the year 2021 blind elk if your still on here i need your help! i have just swapped the rb25 neo into my gts4, all the mechanical work is done but i need help with wiring up the ecu! 

Did you swap the Ring and Pinion? 

 

How much a PITA Is it to shim the front differential. From what I can tell there is two thrust washer with 6 various sizes each for sides and two washers with almost 10 each options for the pinion depth along with a pinion sleeve that comes in 6 sizes. 

There is almost 1.65mm of depth tolerance stacking and with each of these washers/shims running for $5, that's almost $500 to get enough to play whack a mole with setting up the R&P pattern. 

On 5/20/2022 at 1:05 PM, corbic said:

There is almost 1.65mm of depth tolerance stacking and with each of these washers/shims running for $5, that's almost $500 to get enough to play whack a mole with setting up the R&P pattern.

That's why I always just give it to my trusted diff guy to put my Frankendiffs back together.

On 5/19/2022 at 10:19 PM, GTSBoy said:

That's why I always just give it to my trusted diff guy to put my Frankendiffs back together.

I'm state side, so while I have two great diff shops near by, neither is going to stock GTR/Nissan shims. 

On 5/19/2022 at 10:47 PM, GTSBoy said:

No, but they can use whatever shim they have, measure the difference with feeler gauges (or whatever alternative approach they may choose) and then buy appropriate shims as required. Not really any different over here.

Shims are unique to the GTR/Nissan.  A local shop may determine that a longer sleeve is needed, but they are not going to be able to call up NAPA Auto Parts or a Nissan Dealer and pick up a sleeve. 

Also, looking at the FSM - it looks like there is a pressed on bearing for the Snub - sooo I doubt any shop is going to have a dummy bearing to get the initial depth without having to press on - press off the bearing a dozen times. 

 

$150/hr experimenting with all this is going to turn into a $2000 shop bill real quick if I went that route. 

 

 

Le sigh. The shim you want to leave in there may unique to the R200. But I can guarantee you that any decent shop will have OTHER SHIMS THAT WILL FIT, even if they have to bore the inner diameter out or scrape some off the outer diameter, to use as a bloody reference.

It hasn't cost me much to have my trusted diff shop do it.

  • 1 month later...

As you can see the Pan's are completely different. The RB25 pan is a different bolt pattern and the axle tube + differential are mounted forward.  The Axle is nearly touching the oil sump and there is an additional 3 inch gap between the differential flange and the end bellhousing plane. 

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

    • Well, the trouble with that ^^ is: The configuration shown is absolutely a 1-way, not a 1.5-way. There is no way that a 1.5-way can be said to offer LSD action only on acceleration. If Nismo cannot get that right, then it is impossible to believe their documentation. That ^ is not a 1.5 way setup. That is a 1-way.   And so now I have allowed all doubts to flourish and have gone back to look at the MotoIQ video. I originally made the mistake of believing him when he said "this is a 1.5-way" at the ~6:10 mark. Because what he did was take the gear assembly out of the 2-way opening and just rotate it one place to the left to drop it into the 1-way opening. When he dropped it in there, the cam was "backwards" compared to the correct orientation shown in all other photos of that config. The flat shold have been facing the 1° ramp side of the opening, not the 55° ramp side. And I thought, "gee that's cute", but I was concerned at the time, when he put the other ring back on, that the gap between the rings looked like it was wider then in the 2-way config. And then I said a lot of things in my long post on Tuesday that could only make sense if the guy from MotoIQ was correct about what he'd done. BUT... I have now done my homework. I grabbed a frame of the video with the 2-way config, and then grabbed another with the "1.5-way" config, snipped out the cam and opening of that frame and just pasted it direct on top of the 2-way config. I scaled it so that the triangular opening was almost exactly the same height in both. AND.... the gap between the plates is wider with the cam installed in the triangualr opening backwards. That is.... it cannot go together that way. There would be massive force on the plates all the time, if you could even reassemble it.  So, My statement on the matter? The Nismo diff is actually only a 2-way and 1-way. There is no 1.5-way option in it, regardless of what they say. Here's a photo of a real 1.5-way ramp opening from Cusco (along with the 1 way option). And the full set of 1 through 2 way options from their racing diff, which is not same-same as what we'd typically be using, but...the cams work the same. A little blurry, but it comes from this Cusco doc, which is quite helpful. AND.... Cusco do in fact do what I suggested would be sensible, which is to have rings that do 1 and 1.5, and 1.5 and 2. Separately.  
    • Welcome Adam. Car looks great!
    • "With a 1.5-WAY, the LSD is effective only during acceleration."
    • Well it wasn't as easy as I thought.... and it also wasn't in my original manual which I did end up finding. They discuss the process in the Nismo catalogue though and it requires slight machining. Page 145.  NISMO PARTS CATALOGUE 2020
    • I'm an idiot, my intercooler is rated for 1000hp. I had clicked on the wrong product. Knowing the delta P would be nice, but I'm doubtful I'll do it. Now as for an EMAP, that would be great and I'll get around to it eventually but from my findings in my last post, I'm considering a turbo swap now. 
×
×
  • Create New...