damn right i am. if this turns into a flame fest ill lock it and we will never discuss this topic again -Kamin

*this is just trying to make things a little easier for other people

General

Pros

-its an RB! from a skyline!
-closest thing to a real skyline
-I-6 potential
-the awesome sound.

Cons

-Yes, it is more weight, around 150lbs more for a rb25 swap. the weight isnt important tho, its the weight shift. it really depends on engine/transmission and how you mount it (i.e. crossmember or aftermarket mounts), but realistically your looking at 2-3% overall weight shift. if you look at the numbers in a 3000lb car thats only a 60-90lb shift forward. just to put that in perspective, 12 gallons of gas weighs roughly 100lbs so there is more of a shift between a full and empty tank, than a RB swap. IT DOES NOT DESTROY THE WEIGHT BALANCE OF THE CAR

-Parts are still rare and expensive, but things are starting to come over
-mounts or crossmember swap required

RB20

Pros

-cheap
-skyline engine (?)
-WD-racing was saw near 400hp with his
-easy swap
-free revving up to 8k is possible on stock valve train
-excelent gas mileage off boost (it is a 2l after all)
-can make good power with minimal mods.
-sensors interchange with lots of usdm cars

Cons

-SR is easier with same potential (for your lower goal people). out of the box both will make near the same power, and upgrade easily to near the same numbers.
-cheap turbo (ceramic wheel)
-"weaker" tranny, nearly the same as KA/SR trans
-akward intake manifold
- its getting old 89-93 production years
-high mileage engines need proper mantinence ie timing belts and water pumps
- tiny injectors (270cc)
-intake manifold flange is diffrent from rb25 (greddy manfold does not bolt on)
-some rb20's can have the same problem as the early rb26 engines with the crank collar issue

RB25

Pros

-good potential (500+ on stock internals)
-VVT
-strong tranny (also include this when you price rb25s)

Cons

-expensive clips (when you get that strong tranny)
-becoming rare and expensive parts
-weak pistons ring lands
-not full glory as rb26
-another lame turbo, but better than the RB20's
-factory hp overrated (easily achieved with basic swap upgrades though)
-side feed injectors (hard to find)
-akward intake manifold
-custom driveshaft required (unless you use RB20 tranny?)

RB26

Pros

-the GODZILLA of RBs
-most potential of all
-twin turbo stock
-upwards of 300+ out the door
-bullet proof

Cons

-$$$$$
-$$$$$
-r32 crank coller issue (kills motor)
-need for rb25 tranny
-hard to find r33 motors
-impossible to find r34 motors
-did we mention $$$$$?

RB30det hybrid

Using the higher displacement 3 L block from the RB30 engine mated to the RB25 or RB26 head can yield a very powerful engine. Here's a thread with details. http://forums.nicoclub.com/zerothread?id=188136

For Specs on engines and good info also check:
- http://www.meggala.com/nissanrb3css.htm

Team Race Bread - P&J forever!

i like where its going.

i also think we need a RB VS SR VS KA sticky

but i dunno if that would go over well in the RB forum needs to be in 240sx general haha

Excellent sticky!

http://www.myspace.com/twistingmearound

Modified by Kansei240sx at 8:31 PM 10/26/2007

RB20det = Top feed high impedance injectors. Stock is 270cc. Each injector will pass on about 10 ohms. Each is wired in parallel so that the total return to the ECU is ~10 ohms.

RB25det = Side feed high impedance injectors. Stock is 370cc. Each injector will pass on about 10 ohms. Each is wired in parellel so that the total signal return to the ECU is ~ 10 ohms.

RB26dett = Top feed Low impedance injectors. Stock is 440cc. Each injector will pass on about ~ 2 ohms. Each injector is wired in parallel to the ECU but in Series with a resistor. That resistor passes on about 7-8 ohms. The two signals add up to ~ 10 ohms returned to make the ECU happy.

Modified by Eikon at 7:55 AM 9/21/2005

Joshua 1:9 "Have I not commanded you? Be strong and courageous. Do not be terrified; do not be discouraged, for the LORD your God will be with you wherever you go."

exactly how much power can the stock internals hold on an RB20?

Thanks

Maybe this will help.

i paid 330 for mine. that was a complete driveshaft including new ends. if you use parts you have, it would be cheaper.

NICO REGIONAL MEET MARCH 18TH, 2006 - GREENVILLE,SC... PEOPLE ARE INVITED FROM ALL OVER BUT MOST WILL BE FROM SC/NC/GA

Yes you can use rb26 cranks in both. No they're not the same block. RB26 supposedly had larger or stronger webbings.

Thanks!

Ah, ok. But the RB20 and 25 is probably strong as hell, even the small CA18 block or the aluminum SR20 can handle a lot with forged internals.
The crank thing is good, I found forged ones to the 26 but not the others.

Do you know if I can use 26 cams in the 25 head? Diameter and lenght?

/Mike

So anyways, on this custom driveshaft, where can you purchase one at? I was looking at the "where did you get yours" thread and saw 300plus picked a rb25 clip from jarcoinc.com and it came with a stock driveshaft. Can I use that one or would it have to modified in someway? thanks guys!

call a local driveshaft shop for estimates, they are in the phone book.

BTW that could have been easily found by searching if your seriously considering a RB swap the search function needs to be your best friend because its not anything like a KAT or SR.

My floor jack now has MORE clearance (about 1/8") when I push it under the front lip. This is after swapping to RB20, including everything but cruise (kept stock A/C, battery location and size, SMIC, etc). In addition, I now have two PermaCool High Performance fans in front of the radiator, which probably weigh about 5 lbs more than the stock fan setup (they have steel frames and heavy motors). I also have the N1 Dual exhaust, which would seem to be heavier than stock, but I did not weigh it.

At any rate, the springs don't lie. There is no arguing that the RB20 is heavier than the KA24DE, but the center of gravity must have shifted backwards a bit to make the front lip come up. Perhaps that is the extra weight of the exhaust. No matter... the balance has shifted toward the rear, and that ain't bad.

[EDIT] In case I am not being clear, my basically stock RB20 swap shifted the balance favorably toward the rear wheels.

only problem is only a very select few people have weighed their cars PROPERLEY before and after the swap. and only 1 to my knowledge has corner weighed the vehicle. i have access to corner scales at work but have never gotten around to doing my car. maybe i should..

Interested in doing a JZ Swap? check out this!
MyJZswap.com

89' NISSAN SKYLINE GTS-T (RB24)
97' NISSAN 240SX LE (RB26 SOON)

My favorite part about the rb26 is that the entire motor will support over 425RWHP before any modifications need to be made.
This includes, injectors, mafs, turbos, and ofcourse all internals.
it also has internal throttle bodies which create better engine response
Stock bottom end has been taken to over 1000hp.

RB25DET is 9:1 Compression, better low end torque
RB26DETT is 8.5:1 Compression, bring on the boost baby!!

All RB motors are basically Factory Blueprinted. I love seeing the look on people's faces when I tell them that.

sure the engine can see 425whp without much modification but the 10,000$ pricetag for a 26 swap you could fully build a 20 or 25 and see 600whp.

all engines are "blueprinted" thats the list of specifications found in any service manual that is used when the engine is assembled.

Yes, different engines have different size bearings. Instead of a one-size-fits-all-hope-it-works system like some low budget engine manufacturers we won’t mention here (Chevrolet, Ford, etc.), Most Japanese manufactured engines run on exact clearances (blueprint). Because the machines work engine after engine after engine, tolerances vary. To make up for this, there are different bearings, pistons, etc. to choose from. For example: Standard main bearing thickness for grade 1 for the SR20 is 1.977-1.980mm and grade 6 is 1.995-1.998mm (There is only one size for undersize bearings). That’s a 0.021mm or 0.0008” difference between the thinnest and thickest shell for a total of 0.042mm or 0.0016” total difference per journal. This system works awesome in two respects; it ensures that every engine leaving the factory has spot-on clearances (Yes, this means that the RB26 is, for the most part, “blueprinted” in stock form), and it gives high performance engine builders a range of clearance options. The “old” way for “the other” engines is to mike bearing after bearing to try and find a thicker or thinner one to meet your needs.

all of this is from Matt... the skyline pimp... i take no credit i just was lucky enough to get the information

That's all I know.
Thanks for the correction on the ITB, I was a bit tired.

Does that mean that a lot of rebuilds, people used to just slap in some bearings and call it good? And those who get theirs "blueprinted" just means they took the extra time to get their tolerances as exact as they can?

Note to Moderator:
Thanks, and feel free to delete these last few posts as they are definately off topic

all blueprinting means is its built within the specs as the manufacturer reccomended in the service manual.

Quote, originally posted by TOPSECRT88 »

Awesome sticky man. This should eliminate the 100,000 RB20 v RB25 v RB26 swap topics. We shoulda thought of this earlier.

Word. Thats my dilema right now

The factory 26 crank is not fully counter balanced.

Quote, originally posted by David_NISMO »

My favorite part about the rb26 is that the entire motor will support over 425RWHP before any modifications need to be made. This includes, injectors, mafs, turbos, and ofcourse all internals. it also has internal throttle bodies which create better engine response Stock bottom end has been taken to over 1000hp.

Around 400 whp you run out of MAF. Stock injector is a 444cc that runs out at about 440 hp at the motor safely. Stock turbos lose ceramic exhaust wheels.

I have done 654 rwhp on an internally stock 26, and I have ran 137 mph with an all stock internally 26.

The 26 has individual throttle bodies.

As far as stock and 1000hp....like a ticking time bomb. 500 rwhp it will last ok. 600 whp its iffy...

At first glance I, of course, wanted an RB26, seeing as the cost difference in the actual clip was only about 2-3k more than an RB25, but then I began researching what actually went into a swap and what the actual cost would be, and I think I have come to the conclusion that the RB26 is going to be a much more expensive swap compared to an RB25 swap, or perhaps I am just under estimating the cost of an RB25 swap?

So I guess my real question is, If I do an RB25 swap how much more am I going to need after I buy the engine, trans, ecu, wiring harness and how much will it all end up being? Also how much HP can I expect out of a 25, my goal is around 400WHP, would that achievable with an RB20?

Thanks in advance guys.

-Jim


Modified by jimapaloooza at 11:39 PM 6/27/2006

ok i need someone to clarify this one for me... will an RB20 tranny mate with an s13 drive shaft??? or do you need to get r32 gts-t drive shaft or is it a trip to a drive shaft shop and a shaft in the wallet

you know you're driving a real car when you can let your shaft hang.