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:rant: ill take that as a compliment.

why are people so scared of engine work??? atmo and v8 guys thrive on calculations and mixing and matching this with that to get this. everything gets stroked and ported and balanced

turbo guys just wanna push the stock bottom end as far as it can go, if the stock bottom lets go, they put in another one.

rb26 has nothing on 2jz anyway... id be putting one of them in a go kart.

its not that i'm scared of engine work, its just that for 20k, you could have at leaest 100rwkw more with better response than a 20 and you could build it to rev just as far too.

as they say... there's no replacement for displacement

i'm all for pushing the stock bottom end, but rebuilding when it lets go, or dumping an LS in there :rant:

and as for the 2j v 26 thing, they BOTH have their limitations, especially over 400rwkw

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like i said.... RB20 haters... what part of making an RB24 is illegal??? its all neatly contained in what looks like a standard rb20.

removing and transplanting engines takes the spirit out of the car.. rb25's are boring.. they are the middle child.. i would rather spend $20000 on my RB20 and make whatever power it makes than put an rb25 in my r32.

a stock rb26 would tromp the rb20... no shit... but the rb26 belongs in the GTR... like the harbour bridge and bondi beach belong in sydney.

The GT30 sized turbo on the side... guess you could use a highflow, but they are compromised at best. Try reading my post next time.

I have an Rb20, does the job, but I know when I am flogging a dead horse.... An RB20 is dead money. you hit 300rwkw or so, the head is unhappy, you want 400rwkw, you go to a bigger turbo and make the car a track car an RB26 is a more efficient way of doing it... RB26 also has more off the shelf aftermarket support, you get one with stock bores, more future for rebuilds if required.

try finding Rb20 spares new in a few years compared to RB26...

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WIKIPEDIA:

RB24S

This is a relatively rare engine, as it was not produced for the Japanese domestic market. These were fitted to some left hand drive Nissan Cefiros exported from Japan new. Mechanically it is made from an RB30E head, RB25DE/DET block and RB20DE/DET crank with 34 mm height pistons. This engine used carburettors instead of the Nissan ECCS fuel injection system. It is able to rev harder than the RB25DE/DET (as it has the same stroke as the RB20DE/DET) as well as being almost the same displacement as the RB25DE/DET. A common modification is to fit a twin cam head from other RB series motors while retaining the carburettor set-up. The standard single cam form produced 141 PS @ 5000 rpm and 20.1 kgf·m (197 N·m) of torque @ 3000 rpm.

http://en.wikipedia.org/wiki/Nissan_RB_engine#RB24S

Edited by Nic_A31
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yeah, the ze ones are forged form factory aparently

not forged... but over engineered and heat treated.

hmmmmm I has a 1GGZE sitting in the shed...

I should build a go kart...

check out the Sidewinder plans... then modify the rear subframe to take the jz and find a suitable gbox with the axles out the side... like a subaru or porsche. old boy and i put a 4age in one with a renault 5 spd box.

The GT30 sized turbo on the side... guess you could use a highflow, but they are compromised at best. Try reading my post next time.

i read your post, i got what you were getting at with the GT30.... my point being... why is a GT30 the only turbo you can use?? why is a GT30 on an RB24 any different in terms of legality as a GT30, T04, T51, T88 etc... on the side of an rb25, rb26, sr20, ca18, 2jz, etc.

the rb24 part of the engine is just an air pump, so its now capable of pumping nearly the same amount of air as an rb25.. but its stronger than a stock rb25 and revs harder due to its different bore vs stroke.. it can, in theory, support any turbo that an rb25 can support.. the head is where the restriction is... and as far as i can see it... the rb25, rb26 and rb20 heads are all just a chunk of alloy with different holes.. a chunk of alloy designed by a man.. it was made by man, it can be modifed by man.. there is no reason that the rb20 head cant flow the same, just noone has tried to really push it as the $$ value is too great compared to an rb25.

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RB20 head can't be that bad, my cefiro arrived with a rb20 head, east bear 1.8mm HG on a rb25 bottom end.. Was good enough to compete in the advan drift meeting.. Theres an r32 about in japan built by garage testorossa (sp) with an rb20 head on 30 bottom end.

Hands down would take a 24 if it had enough research and $$$ are behind it.

That is just doing something different - for different's sake.

Nothing more.

The cost to get a RB20 head on a 25 bottom end is... stupid.

Nothing lines up. That would have been nothing more than a "it can be done" motor, well we all know anything can be done - it comes down to money.

Why would you waste money putting a RB20 head onto a block that it doesn't even line up with for less flow? :)

Half the jap stuff is like that. Its not the easiest, or cheapest, or best - it is just done to prove it can be, well big deal to that. Not everyone has endless budgets for no added benefits

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RB22 = 82mm pistons (4agze, tomei or custom)

RB23 = 82mm pistons, RB25 crank and rods

RB24 = 82mm pistons, RB26 crank and rods

I thought RB26 and 25 had the same stroke? so if they have the same stroke and same piston size how does one end up being a RB23 and the other a 24?

Not being a smart ass, genuine question

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That is just doing something different - for different's sake.

Nothing more.

The cost to get a RB20 head on a 25 bottom end is... stupid.

Nothing lines up. That would have been nothing more than a "it can be done" motor, well we all know anything can be done - it comes down to money.

Why would you waste money putting a RB20 head onto a block that it doesn't even line up with for less flow? :)

Half the jap stuff is like that. Its not the easiest, or cheapest, or best - it is just done to prove it can be, well big deal to that. Not everyone has endless budgets for no added benefits

true that.... not all jap stuff is to be taken as gospel... ive seen some horrid things done by some top workshops that dont run or idle but are told them has a grumpy race engine and its not being revved hard enough... ahh no sorry, it has a head that doesnt line up with the inlet or exhaust, and a cam that has soo much overlap that the valves are still open on combustion.

I thought RB26 and 25 had the same stroke? so if they have the same stroke and same piston size how does one end up being a RB23 and the other a 24?

Not being a smart ass, genuine question

i may be wrong here but i they have the same rod length yes... different crank, different pistons.. stroke may be the same but bore vs stroke is different, rb26 rev harder than rb25 due to the different bore vs stroke.. i think the rb25 is over square... so it would make more low end grunt off boost than the 26 off boost...

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not forged... but over engineered and heat treated.

check out the Sidewinder plans... then modify the rear subframe to take the jz and find a suitable gbox with the axles out the side... like a subaru or porsche. old boy and i put a 4age in one with a renault 5 spd box.

i read your post, i got what you were getting at with the GT30.... my point being... why is a GT30 the only turbo you can use?? why is a GT30 on an RB24 any different in terms of legality as a GT30, T04, T51, T88 etc... on the side of an rb25, rb26, sr20, ca18, 2jz, etc.

the rb24 part of the engine is just an air pump, so its now capable of pumping nearly the same amount of air as an rb25.. but its stronger than a stock rb25 and revs harder due to its different bore vs stroke.. it can, in theory, support any turbo that an rb25 can support.. the head is where the restriction is... and as far as i can see it... the rb25, rb26 and rb20 heads are all just a chunk of alloy with different holes.. a chunk of alloy designed by a man.. it was made by man, it can be modifed by man.. there is no reason that the rb20 head cant flow the same, just noone has tried to really push it as the $$ value is too great compared to an rb25.

an RB24 with a GT30 is compared to an RB26 with N1's power wise, and you get both cars pulled over, which ones will have more issues?

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With its longer stroke the RB26 is closer to square than the RB25 meaning the 26 'should' (longer stroke = more down low and less revs up high) have more down low and not rev as well, however the difference in stroke is pretty tiny!

Things that limit the Rb26s low end grunt would be a lot more turbo in comparison to a Rb25 and some will also say the shorter runners in the inlet manifold and the RB25 doesnt rev as well due to things like hydraulic vs solid lifters. thats my pretty noob spec take on it

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The only difference between the 25/26/30 is the stroke (the 30 needing a different block to accomodate the extra stroke length). An RB26 crank can go into an RB25 but there are a few walls to get over with it. All drop in stroker kits I've come across can fit either the RB25 or 26. The blocks are nearly the same, the bore is exactly the same standard.

The heads and manifolds are quite different though...

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like i said.... RB20 haters... what part of making an RB24 is illegal??? its all neatly contained in what looks like a standard rb20.

removing and transplanting engines takes the spirit out of the car.. rb25's are boring.. they are the middle child.. i would rather spend $20000 on my RB20 and make whatever power it makes than put an rb25 in my r32.

a stock rb26 would tromp the rb20... no shit... but the rb26 belongs in the GTR... like the harbour bridge and bondi beach belong in sydney.

hmm you know the rb24 have a love of splitting bores don't you? i have a purple 4dr 32 in here that is rumored to have the hpi engine in it and its also got a split bore :)

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the rb24 part of the engine is just an air pump, so its now capable of pumping nearly the same amount of air as an rb25.. but its stronger than a stock rb25 and revs harder due to its different bore vs stroke.. it can, in theory, support any turbo that an rb25 can support.. the head is where the restriction is... and as far as i can see it... the rb25, rb26 and rb20 heads are all just a chunk of alloy with different holes.. a chunk of alloy designed by a man.. it was made by man, it can be modifed by man.. there is no reason that the rb20 head cant flow the same, just noone has tried to really push it as the $$ value is too great compared to an rb25.

There is quite a lot more "meat" in 25/26 heads than the 20...going by what ive seen you would be lucky to get a 20 inlet port the same size as a standard 25/26 head without finding water jacket poking its head up to say hi.

the small bore also serverly limits the valve sizes that could be used.

Im sure you could get the 20 heads to flow well enough given enough R+D (re: $$$$$) but buy the time you have done that you could have bought an OS Giken RB31.

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