R33 Rb25 Vs. R34 Rb25

[old240sx]

I recently bought a s13 and have been wanting to do a 25neo swap. I live in the us so neo motors are a rarity and the only place I can find them are from those sketchy canadians up north. And from them who knows what your gonna get. I can find r33 25's all day even in the states for a little extra but I dont know the potential I would be missing out on. I've heard a lot of good things about the neo besides the price of clutches and was wondering your thoughts. From what I here if anyone would know about these motors it would be you guys.

[The Mafia]

well, for starters, I'm pretty sure the NEO's are fitted with RB26 rods from the factory so that would make them stronger.

They are also 9.3:1 Compression as opposed to the 9:1 compression of the R33 RB25

[old240sx]

I've read they also have solid lifters and the vvt as apposed to the r33's but I was wondering if any body has pushed them and if they really mad more reliable power than the r33's.

[r33cruiser]

most rb's have vvt. its called NVCS.

also the neo engine is meant to be more 'environmentally' friendly aparently

[STATUS]

The NEO tends to make more power for the same amount of mods better breathing due to head package). They are both as reliable as each other but the Neos' tend to have lower mileage which helps.

[old240sx]

Someone told me that the r33 was only good for 550, but the neo was capable of around 700.

[R34NRG]

the 33 is also only 187kw compared to the 206 of the gtt

[DLOOOK]

Also consider the availability of aftermarket turbo kits and ECU's (ie Power FC). Mods for the 33 are more readily available and cheaper than for the 34. NB: PFC are discontinued for RB25's

[joeyjoejoejuniorshabadoo]

my mate and i have a 25t and a 25t neo with the exact same mods.

the neo is the tinyest bit better due to the compression.... but not a heap

but they are newer

[shnaped_second]

well, for starters, I'm pretty sure the NEO's are fitted with RB26 rods from the factory so that would make them stronger.

They are also 9.3:1 Compression as opposed to the 9:1 compression of the R33 RB25

interesting, can anyone back this up?

[STATUS]

Also consider the availability of aftermarket turbo kits and ECU's (ie Power FC). Mods for the 33 are more readily available and cheaper than for the 34. NB: PFC are discontinued for RB25's

turbo kits from R33 fit perfect on R34, i do it all the time with the trust kits.

[Birnie]

I've also heard they have stronger internals, as in the rods.....so that's a plus making it better for bolt on mods

[R338OY]

For a little more money and patience a NEO is definitely better. If you're not anal about a few HP and some extra mileage the R33 RB is great.

[PSI Parts]

most rb's have vvt. its called NVCS.

From my understanding the NEO has a constant cam variation capability compared to the standard On/Off of the old RB25.

[Adriano]

From my understanding the NEO has a constant cam variation capability compared to the standard On/Off of the old RB25.

Its a very common misconception. The r34 vct works exactly the same as the r33 system

[BLK33T]

doesn't the neo have both intake and exhaust NVCS?

also standard the NEO has smaller injectors than r33?

and a slightly better stock turbo...

both are good standard but the NEO would be the better choice because they're are generally newer.

[GTRsean]

Bloody net dropping out!!!!!

Here we go, I'll retype again...

NVCS is only on one cam.

They run narrow body injectors

Stock turbo is weaker when boosted due to nylon comp wheel, ceramic exhaust wheel like r33

Mate Ben has R34 GT-T

Stock engine

tomei poncams 260

800cc inj

044

fuel reg

z32

power fc

front mount

plazma man plenum

T04Z

363RWKW @22 psi Z32 starting to max out.

He has a built RB30 bottom end to swap in due to nos system he intends to use with setup, no bull.

[discopotato03]

The way I look at it is that it makes a bit more grunt in factory trim so that can't be a bad thing . The electronics running it are a bit more advanced so if you can get control of those then its tighter controls IMO .

I think the non hydraulic buckets are a bonus and will open up your choice of cam profiles . If you really want to I'm sure there are ways to get larger injectors into them .

Also don't write off RB26's if you can get them for reasonable money , a few people have used those in the US .

Further O/T . If I was over there I'd be doing a killer KA24DE-T because there are so many parts available for them and they are std (DE) in a USDM S14 anyway . I guess its a case of how much your prepared to pay to be different . I don't remember the exact cc figures for both KA24 and RB25 but there's probably only 100cc's in it if that .

Cheers A .

[GeeTR]

Agreed, rebuild your KA and leave world supply's of RB's alone lol

[gotRICE?]

Further O/T . If I was over there I'd be doing a killer KA24DE-T because there are so many parts available for them and they are std (DE) in a USDM S14 anyway . I guess its a case of how much your prepared to pay to be different . I don't remember the exact cc figures for both KA24 and RB25 but there's probably only 100cc's in it if that .

And an extra 2 cylinders bobbing away in the RB? Surley that counts for something?