R34 Rb25det Neo Vs. R33 Series 2 Rb25det

[pricer-1]

So I have been looking into a RB swap for my S13 and I think I want to go with the R34 Neo but I have a few questions about differences between the Neo and Series 2 engines. When it comes to upgrades or even just OEM parts will the parts for a Series 2 motor work on a Neo? Physically what are the differences? Also what parts should I consider replacing before installing the engine into my S13?

[Bass Junky]

Neo is totally different head to Series II R33.

Solid lifters, different cams, GTR rods, slightly different VCT.

Head is NOT interchangeable.

[silverr34gtt]

Theres plenty of neo specific head upgrades like poncams and fine tune timing belts ect. the stock rb25 neo has superior torque and power to the earlier rb25 also.

Parts to replace. Might want to look at a set of splitfires, i had problems with standard coilpacks failing. Other than that i cant think of anything, unless u want to go for extra power.

Edited September 21, 2007 by silverr34gtt

[pricer-1]

Theres plenty of neo specific head upgrades like poncams and fine tune timing belts ect. the stock rb25 neo has superior torque and power to the earlier rb25 also.

Parts to replace. Might want to look at a set of splitfires, i had problems with standard coilpacks failing. Other than that i cant think of anything, unless u want to go for extra power.

I have seen a lot of people talking about replacing the water pumps, oil pumps, time belt, timing belt tensioner and idler pulley, etc bc the engine is most likely coming from a junkyard and has been sitting for a while. Do you think it is all necessary precautions?

[Dale FZ1]

Water pump, timing belt + idlers, crank + cam seals, various water hoses. From the viewpoint of ensuring absolute reliability in those areas - YES. Oil pump as a service issue though, I doubt it.

Some of the parts aren't particularly cheap, but if you consider the time + labour factor involved once an engine is in the car, it is a smart option while the engine is sitting on the bench/workshop floor.

[timheather]

Correct me if I'm wrong, but I heard that with factory internals, the s2 can be pushed further than the neo because it has lower compression? Is this true??

[Al]

I would personally go for the NEO.

[Nismo_R33]

How about the turbo charger? Are they the same?

[RB30-POWER]

Both type of Rb25DET engines have same static compression ratio. 9.0:1

Rb25DET Neo has same turbo as series 2 R33 RB25DET, but has the larger (OP6) exhaust turbine housing. Same housing as used on the VG30DET. (Single turbo engine)

[Col-GTSX]

Honestlly the Neo motor is going to be younger, so it would be the better option...

However that said some second hand Neo's can be rather expensive compaired to theolder S2 rb25, so I guess you just need to weight it up...

But on the solid lifters alone id be buying a neo motor...

[GOLD_JET]

so is the neo definatley the best. looking at getting one second hand for a good price. is this the way to go or s2 25. cheers

[R31Nismoid]

It all depends on what you want to do, what you plan on down the track, and how much money you have.

[GOLD_JET]

it somes with hks fuel rail bigger injectors, fuel reg and better coil packs. i have a good turbo so prob just a computer and i guess i would be happy for a while. but just wanna no. some people say s2 25 is the best and some say neo. just real confusing. dont wanna get the wrong one hahah

[Al]

Another issue to consider is what ecu you plan to use.

For example: At this stage in time, the Wolf V500 is not yet fully compatible with the NEO, but i know they'll be fixing that soon.

[R338OY]

Go for the better, newer Neo if you can afford it.

S2 RB is great engine too, and will be cheaper to buy and probably cheaper to mod (if thats the plan), but it's not as advanced as the R34 Neo.

The Neo is more enviromentally friendly. Guess that's not important on this forum

[GOLD_JET]

yer i prob will go the neo. i donno what comp yet was thinking apexi power fc but yer not to sure yet.