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I've been looking into building an RB25 on the side for awhile and finally came across a well priced one. I have a few quick questions before I move forward as I know nothing about the neo engines. 

1. What exactly is different between an S2 RB25DET and an RB25DET NEO? From what I have read, it seems superior in everyway. 

2. Anything weird I should know about putting these in an R32? Is there anything vastly different between an S1/S2 RB25DET swap besides ecu/wiring?

3. This is an auto RB25DET NEO. Besides the tranny and ecu, anything else that is different due to auto? I would purchase a new R34 5 speed or CD00X 6 speed to accompany it. 

Thanks!

Edited by TurboTapin
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1. Yes, it kinda is. In terms of differences, it has a different head, and a different block, as well as a different turbo and uh, different wiring and ECU, so I mean yeah it's a completely different engine (but also very similar.. paradoxically).

2. There's writeups about this, I would wager @GTSBoy will know.

3. No. In-fact you can re-use the Auto ECU/Loom for the motor in a manual car with no worries, and tune it with Nistune if you like.

1. NEO motors use solid lifters, however it's shim over bucket where as the RB26 is bucket over shim. Still good, but you need the correct tolerances if not when you kiss the limiter you'll shit out shims.

2. Wiring realy

3. Remove the auto spigot

Just now, Kinkstaah said:

and tune it with Nistune if you like.

Pretty much compulsory. It's the only way (other than an aftermarket ECU) to get the engine to run without emo fault codes about missing TCS, ABS, etc etc. Plus there's all manner of bullshit in the boost sensor & stuff that needs to be gotten rid of.

Search. Many many posts exist.

Thanks everyone for the quick feedback. I've searched but wanted a quick response from people knowledgeable in NEO's as I need to put an offer on it right now before it disappears. Wiring/ecu isn't an issue as it's in my line of work and I'm already familiar working with nistune.

Just wanted to confirm there's nothing mechanically funky with these compared to regular S1/S2 RB25DET's that would cause me any big issues. 

Thanks again. 

Edited by TurboTapin

The throttle body does have a silly electronic blade on it which closes for 90s style traction control. Some of the Stageas didn't have them, so if you have one of these ones great! If not, weld the stupid thing open OR just run an aftermarket plenum/intake OR one off a R33.

6 minutes ago, GTSBoy said:

My TCS TB is still installed. Has never moved from the fully open position because there is no TCS CU installed to make it move.

I thought it would have closed (assumed default position), good to know it doesn't shut :)

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