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How To Tell Between Rb25Det And Rb25Det Neo?

xntrq
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xntrq Veteran

xntrq

Posted
Posted

I know this may be covered already but I have only found conflicting answers.

How can I tell if a motor is a RB25DE or a RB25DE NEO?

Where would a stock R33 GTS-T turbo be located?

What are the differences between the mentioned motors and the intake manifold, being a Y-Split or a single (as seen in most DETs)?

f8066f67.jpg

  • Like 1
GTSBoy Grand Master

GTSBoy

Posted
Posted

The pictured manifold is from a DE Neo. That's the only engine that had it. The R33 RB25DE and DET both had similar looking single inlet plenums and TBs. The DETNeo also has a single inlet plenum but has a different TB. It has traction control, so there is a whole extra butterfly and motor to drive it upstream of the main TB. The crossover pipe is therefore shorter.

Neo DETs have an OP6 turbine housing. Of course these can be retro fitted onto older engines, so it is not a 100% proof of Neo-ness.

A stock R33 turbo would be located on the exhaust manifold, in exactly the same place as any other twin cam RB engine's turbo.

  • 3 weeks later...
webber Proficient

webber

Posted
Posted

As mentioned above, people retrofit and bastardise engines for all types of reasons.

Head Casting Numbers, Most conclusive method for identifying heads. there will be a casting version number next to this identification number. IE. 5L7 3 would be the third revision casting of an R34 RB25DE. MORE INFO HERE

Otherwise if you have just a block, look up the engine number and make assumptions based on that. FOUND HERE

I have updates for both the register & the casting page. Just so lazy to type it all out.

  • 1 month later...
xntrq Veteran

xntrq

Posted
  • Author
Posted

Bump with a new question.

How to tell difference between R33 RB25DE non Neo to a Neo or DET? I have a hunch that I've got a DE sitting around but unsure if it's just a non neo DE or DET. To me they look identical but doesn't have a turbo exhaust manifold. Though when i bought this car in question, i found pieces if paper inside with PSI numbers and lap times, car had turbo timer and a racing clutch and pod filter. Everything says it's a DET but there's no turbo/turbo manifold so i think it's been converted to NA.

GTSBoy Grand Master

GTSBoy

Posted
Posted

Nup. Turbo and manifold would have been sold off to someone or taken by original owner to use on another/next car.

I think the R33s had different sized throttlebodies between turbo and non-turbo. Not sure what sizes they are. If the engine still has its cross over pipe, then the BOV on it will indicate turbo engine. If there is a water feed pipe from the beack end of the inlet manifold water plumbing around the back of the head to where the turbo would be, then that indicates turbo engine. Likewise the oil supply and oil drain back to the sump under the turbo.

  • 7 years later...
Smokey_1507 Contributor

Smokey_1507

Posted
Posted (edited)

Sorry for bringing up a old thread but I’m having trouble identifying what engine I have.. is it a neo or s2? It has a plastic cas for a neo, turbo is a 45v4 , 75t block, no igniter on back of the block for coil packs..  I don’t wanna start spending cash until I know what parts to buy.. cheers ? 

9FEDBB23-EA47-469E-9FE9-4D507F42461B.jpeg

DC0C6D48-CE45-4700-BF40-47EB748AD5E6.jpeg

382BF84A-868C-4FA0-A339-857AC3B913AF.jpeg

Edited by Smokey_1507
KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

There were a few "transitional" engines that had the Hitachi CAS but were not Neo engines.  My theory is that you can tell by the ECU plug. The R33 is slim and has two rows of pins. The R34 (Neo) has 3/4 rows of pins. I used to know the colours  of the plugs but maybe someone else can tell you.

  • Thanks 1
Ben C34 Grand Master

Ben C34

Posted
Posted

Vct connector is heaps different, pre neo has external Vct drain at front exhaust side, that should be reasonably obvious.

Coil packs bolt in differently

What are you buying?

  • Thanks 1
Smokey_1507 Contributor

Smokey_1507

Posted
Posted (edited)
2 hours ago, KiwiRS4T said:

There were a few "transitional" engines that had the Hitachi CAS but were not Neo engines.  My theory is that you can tell by the ECU plug. The R33 is slim and has two rows of pins. The R34 (Neo) has 3/4 rows of pins. I used to know the colours  of the plugs but maybe someone else can tell you.

Cheers KiwiRS4T, next time I’m back home I’ll check the ecu plug... the more I look at different pics of neo’s and s2’s I get confused at the differences!! 
 

 

2 hours ago, Ben C34 said:

Vct connector is heaps different, pre neo has external Vct drain at front exhaust side, that should be reasonably obvious.

Coil packs bolt in differently

What are you buying?

Ben C34, 

I’m looking at service parts at the min, timing belt, water pump, spark plugs.. I’ve just got the car back from the painters and had an arch, side skirts, front and back bumpers fixed and painted.. I’ve just put a custom stainless exhaust on from the cat back ( sticks out a little too much, may take it back a little bit!) the next big thing will be injectors and turbo + link ecu and a tune to see what it puts out.. I’m not looking for crazy power.. it bothers me that I don’t know if it’s a neo but when I’m home I’ll check for the vct drain and ecu plug!

i have kinked tension rods, rear camber arms, toe rods, traction rods ready to be fitted when I get back. 

the video it sounds like something is slipping in the engine, possibly a belt or could be bad audio but I heard something that doesn’t sound right  ?‍♂️

0526D834-2A18-431F-938A-1AE9D088D4C4.jpeg

1FEC7ACB-FB0C-4787-9275-51147ADB279B.jpeg

589FA580-4151-4A9C-90CE-D4DC980DA548.jpeg

8D39099B-3A3A-4F25-B51B-F87FFA7D7DCB.jpeg

Edited by Smokey_1507
Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted
2 hours ago, KiwiRS4T said:

There were a few "transitional" engines that had the Hitachi CAS but were not Neo engines.  My theory is that you can tell by the ECU plug. The R33 is slim and has two rows of pins. The R34 (Neo) has 3/4 rows of pins. I used to know the colours  of the plugs but maybe someone else can tell you.

This theory is flawed, especially if a moron (like myself) has put a R34 NEO motor into their R33 using the R33 loom & plenum :)

Best way is to locate the front passenger side head drain, it's non-existent on a NEO.

  • Thanks 1
Smokey_1507 Contributor

Smokey_1507

Posted
Posted
5 minutes ago, Dose Pipe Sutututu said:

This theory is flawed, especially if a moron (like myself) has put a R34 NEO motor into their R33 using the R33 loom & plenum :)

Best way is to locate the front passenger side head drain, it's non-existent on a NEO.

Cheers I’ll check it out or get someone too ASAP!! 

  • 7 months later...
ADH_A31 Newbie

ADH_A31

Posted
Posted
On 24/06/2020 at 6:15 PM, Smokey_1507 said:

Sorry for bringing up a old thread but I’m having trouble identifying what engine I have.. is it a neo or s2? It has a plastic cas for a neo, turbo is a 45v4 , 75t block, no igniter on back of the block for coil packs..  I don’t wanna start spending cash until I know what parts to buy.. cheers ? 

9FEDBB23-EA47-469E-9FE9-4D507F42461B.jpeg

DC0C6D48-CE45-4700-BF40-47EB748AD5E6.jpeg

382BF84A-868C-4FA0-A339-857AC3B913AF.jpeg

bro i’m looking for like this one intake manifold 

how can I fond one for my RB25de neo?

 

thank you

  • 2 years later...
Quincy Newbie

Quincy

Posted
Posted (edited)

@Ben C34 so does this mean i have a neo? I recently took out my CAS to paint as well and someone told me that it was a neo CAS but when i bought the vehicle (A31 cefiro) i was told the engine was just a Rb25 s2

SmartSelect_20230228_003346_Gallery.jpg

20230227_173738.jpg

Edited by Quincy
GTSBoy Grand Master

GTSBoy

Posted
Posted
49 minutes ago, Quincy said:

ooh so i got a neo head on a regular De s2 block?

Would be very unlikely. Neo combustion chambers are about 10cc smaller than the vanilla 25s, and the compression goes through the roof. Neos use RB26 rods and different pistons, with the differences being in the height of the pin and the shape of the crown. There is less dome, so they don't stick up into the chamber as far.

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