King of the 2.5turbos. Rb25 or 1jz?

[tomj]

Jim i suggest you start a thread called "nissans cars versus toyota's car" I dare say this was a thread about the engines not the cars.

end of the day a 1jz is better then a rb25. Simple.

[JimX]

Better at what?

[Bullet-32]

I vote the Rb25 since it has a background from nissan , but in standard form the Toyo is stronger in terms of standard with no modifcations to the motor.

[DaiOni]

1JZ in a chaser is a serious combination of luxo looks and awesome power (many over 500ps). If flicking through the pages of japanese magazines such as option, every month, is any indication - there are a lot more serious 1JZs than there are RB25s (these days). That's probably got a lot to do with the fact that a chaser is a class above a non-gtr skyline (whether you like to admit it or not). A 1JZ in a soarer is another matter altogether - but the quality of the engine remains the same.

[usuckpoo]

there was this test on zoom about placing a 50 cent coin on the cam cover of a reving 1jz to prove how smooth it was....

has anyone did it on a skyline?

[HKSgtst]

i'll put my money on the 1JZ. I sat my friend's soarer, just 0.6bar, fmic, exhaust and it made 210kW at the rear. good stuff

[Tosh]

I personally would choose the 1JZ over the RB25 but I can't say which is "better" as I have neither the mecahnical knowledge nor the experience to be able to compare the 2 fairly.

I think this comes down to what people feel is more important to them and what they like. Weather you choose a motor because of it's tuneability, how much power it'll handle on stock internals, parts availability, manufacturer.... whatever it may be.

This thread is a matter of opinions... not fact, and no one has an incorrect opinion (misguided or technically incorrect perhaps but not an incorrect opinion)

[nmcmahon83]

what about the 2JZ :D??? (sorry to open up another can of worms, but if the 1JZ is taht good, is the 2JZ far superior???

[JimX]

I vote the Rb25 since it has a background from nissan , but in standard form the Toyo is stronger in terms of standard with no modifcations to the motor.

You've hit the nail on the head with that last part. The main thing people seem to focus on about the 1J (and 2J) is the power it can handle. But what about the rest of it? Does the head flow the same, does it rev similarly, does it sound as good (), does it respond the same way to mods, is it as cheap to mod, etc? If all of these are similar in both engines as I think they are, you're just back to the strength of the bottom end, which is only one part of the engine. Doesn't really put it in "a class ahead". I think it would be better to say that the RB25 or 1JZ are a class ahead of Holden's Buick 6 because there are a lot of fundamental things better on the former 2.

Sydneykid can also be quoted on these forums for saying that the Supra box is agricultural compared with the R33 GTS-t's. But man, why would you bother thinking about that when you're hung up on the bottom end

[Tosh]

The 2JZ isnt comparable to the RB25 as it's a 3L twin turbo six that puts out 280hp (yeh right toyota.....) from the factory

it is more commonly compared to the RB26

[GTRgeoff]

there was this test on zoom about placing a 50 cent coin on the cam cover of a reving 1jz to prove how smooth it was....

has anyone did it on a skyline?

That was the V8....got one and it's true

[maxim]

The 1jz definitely seems to enjoy a reputation of being equipped with a 'stronger' bottom end when compared to the RB25. Perhaps this is partly attributable to the lower compression ratio reducing the potential for detonation in comparison to the RB's higher 9:1, all other things being equal.

From what I can gather, the generally accept power ceiling on a stock RB25 is ~250kw atw, roughly 332flywheel kws without experiencing rapidly increasing probabilty of engine failure with extended use. I still think thats pretty amazing seeing factory is a relativley paltry ~187kw....

[mx83toy]

the coin test was with a 1J as well (a little party trick of mine:) the falcadore guyz freak) the 1J head can flow around 450 to 500 hp and the 2J up to around 600 without porting and mods and in the "power mode" my car shifts at 7700 so they are revvi...

the 1J and 2J are almost identical in manyspec the only major diff is better porting and 10mm longer conrods

as said above an RB25 can handle 250KW ATW which most ppl dont push too much beyond...which puts the strength of the 1J kinda out the door but its nice to know that its harder to break (get some bad tuning and you can breke it at 200kw)

as far as mods go well i find second hand goodies are harder to get that bolt straight into place but can be sourced

a massive advantage of the 1J over the RB's check out the price of one (i can get complete 1J with turbos comp ect for 1500 now thats cool for what you get hey???)