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Hey guys, so I was reading through different threads, but no one seemed to talk about a couple things:

1st picture: The Awd sump doubles as mounting points for the transmission.  If you use a RWD sump, you lose those bottom 4 mounting points as there is no way to mount the two (r33 rwd) brackets to the NEO block (picture 2) like on the series 2 r33 rb25 (picture 3 shows the bracket mount points on r33 block).  For those that have converted awd to rwd - are you just not using those 4 bottom trans mount points?  Obviously, you could cut and weld the AWD sump and call it a day, but my preference is to not hack anything.

4th picture:  pilot bushing for r33 rwd trans shown next to where it should go on the Neo motor, but clearly has a different size pilot bushing for auto.  I see people are talking about pulling this auto bushing out, but then what? The manual bushing is too small to fit ?

All people seem to talk about is whether or not a RWD sump will fit an AWD block ?

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Edited by xRacerx972
Info found, updated question
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https://www.sau.com.au/forums/topic/475806-rb25-neo-awd-to-r33-rwd/
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Its got the 23U stamp.

It was sold as a Stagea engine, but the ECU 23740-cr700 cross references to a Cedric/Gloria. The turbo also had a metal compressor wheel fwiw, which definitely came stock on this motor as nothing seemed to have ever been worked on.

Anyhow, Im assuming the 75T block has the mount points I need.  If im not mistaken - my series 2 rb25det motor is the 75T block.

I guess its time to hack up the AWD oil pan..

I didn't use the bottom mounts and went with an ASR sump. The pickup was modified to suit the ASR sump as well.

Totally binned the spigot as it's not needed.

Bad photo, but this is how it looks atm mounted to a RWD R33.

20190104_180119.thumb.jpg.e86cf761212fd0698f47f7549cca8b88.jpg

3 hours ago, xRacerx972 said:

Anyhow, Im assuming the 75T block has the mount points I need.  If im not mistaken - my series 2 rb25det motor is the 75T block.

Yes, absolutely correct Bret, the 75T was used in R33series 1&2 and R34 Neo RWD RB25 Skylines both turbo and N/A. 

  • 2 weeks later...

So I ended up filing a notch in the auto trans bushing and was able to pull it out that way.

After some beating the steel rwd pan, i was still having some fitment issues - so I ended up cutting the awd pan and having it welded shut.  It was a little bit of a pain, but you end up with a much nicer part than going the RWD sump route.

Just some extra info in case anyone else is thinking of doing a similar setup:

The AWD sump is a very tight fit with the RWD crossmember and with power steering lines.20190122_204949.thumb.jpg.a876cc1f63d99a23ba5607416f50cc49.jpg

The "Freddy" intake manifolds are also a very tight fit against the clutch master cylinder and required the forward stud from a series 2 rb head.  The forward NEO stud was too short.

The HKS manifolds don't allow much larger of a turbo than what I'm using (borgwarner s257 t3). I'm very close to the crossmember with the compressor housing and both power steering lines from the reservoir will need to be moved.  I also had to cut the passenger side engine mount to allow clearance for the compressor housing.

 

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20190123_104400.jpg

Something of relevance to the confusion over the Neo/vanilla nature of the engine in question.

There was a short period of time where the RB25s in Stageas were a weird hybrid halfway engine using some vanilla 25 and some Neo stuff.  They are effectively a total orphan and a complete pain in the arse because of it.  Best avoided.  I looked into it a long time ago when trying to buy a Neo for my conversion and worked out what head and all that stuff was on them, discovered I did not want one because of all that and promptly forgot all the details except the cautionary warning to not consider buying one.

Once you have one, all the shit you have to do to make it work is a bit of a waste of time that you have to back out if you later need to change to either a Neo or a vanilla 25.

Just chimeing in to say that Y34 Gloria's/cedrics did have an AWD model with RB25DET. As far as mounting, i would guess it's a unique situation because chassis is half unique and half 350Z/M35 platform.

The block mounting points are the same, the only thing i noticed was the metal mount brackets that bolt to the block pointed forward.  If you were to use these, it would jam the rear of the engine into the firewall.. 

And apparently I spoke too soon.. I got the trans bolted to the engine and the engine bolted to the crossmember.. i just saw that the trans support is a couple inches too far forward and the actual trans bolts are too far backwards..  so ill have to have something fabricated to support the trans that bolts into the standard location.. it just never ends..

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