I searched, Trust me. RB25 vs sr20, Different questions...

[drift freaq]

Originally Posted by jamanrr

No crap. Every RB owner I have ever seen including the 20 have had issues of some kind. I have been pleased with my sr -- 3 years now and over 18 months of mid 300s whp and have not blown up yet. Knock on wood. Like everyone says in this thread take care of your SR and your SR will take car of you. I change my oil with Mobile 1 every 2 thousand miles and change spark plugs every 6-8 thousand miles. Better to be safe than sorry.

More hearsay by someone who has no first hand experience with RB's, based on their speculative opinion.


Please if your going to comment in thread don't spout hearsay. I have seen people have problems with SR's and I have seen people have problems with RB's.

Stupid in stupid out. I.E. if you don't know how to do things right you will have problems. Lots of jacked up RB installs lots of jacked up SR installs.


Someone please kill this thread.

[Seanbonham]

Originally Posted by drift freaq

Honestly right now I would say your bets are higher on a a low mileage RB over here.
The days of low mileage SR's are indeed coming to an end. Though you have to realize something. 100,000k is still on 62 thousand miles. That is still low mileage . Plus fact is you have been buying running cars that have not been crashed so of course the mileage will be higher. LOL

As far as it being beat on you can inspect a clip and tell immediately if the engine was beat on or not just by how stock the clip is. For one thing. The other thing you can do is a cylinder leak down test and compression test, you can also inspect the turbo.


The RB is less likely to be beat on as well because it has enough power stock and its coming out of a GTST which like I said before is not exactly the performance model version of the car.

RB's can spool damn fast with the right turbo. I know my GT2530 on my RB spooled instantly and my friends with SR's were shock by the way the car pulled like mad.

Either way indeed both engines are fun.

Just because you are in Japan it does not mean you know anything about the engines imported over here. Unless you work for an exporter over there you really have no idea what we get here as you are over there.

To the OP if you are living in Texas then forgot about stage builds and think about cooling, of course depending on where you are in Texas the humidity could play in your favor as 100 degree temps with high humidity are much more forgiving on a Turbo engine than 100 degree temps with no humidity i.e. wet heat vs dry heat.

Though with a RB in your car cooling cooling cooling cannot be stressed more.

Drift,i'm sure i can search and find this out, but i figured it might be nice to get a free knowledge ride...do you know of what cooling stuff i need to keep my rb25 nice and cool? What fans fit, etc.

[chituntang]

Originally Posted by rex2sx

To answer your post.
Please show mwe what is interchangeable between RWD and RWD Sr20s? Ive had both and VERY FEW things are.

3. You to run at least t28 ,MAF, tune, bigger injectors, and an FMIC to get to 300

2. Read the whole damn thing (the last part)... What I am trying to say is RWD SR parts are easier to come by, but if something major happens, you will have to wait, both SR and RB. I know only a few things are for the SR, but it is better than nothing like the RB.

3. But it is a turbo upgrade with supporting mods (what you said). Just like a turbo kit does not come with a turbo only...

[jamanrr]

Originally Posted by chituntang

2. Read the whole damn thing (the last part)... What I am trying to say is RWD SR parts are easier to come by, but if something major happens, you will have to wait, both SR and RB. I know only a few things are for the SR, but it is better than nothing like the RB.

3. But it is a turbo upgrade with supporting mods (what you said). Just like a turbo kit does not come with a turbo only...

westcovnia?? nissan
courtesy nissan
bill titus Nissan

not to mention enjunku and frsport all have sr parts and in huge supplies. Some of the Nissan dealerships even stock select RB parts. So the parts are out there. Like has been said though SRs especially s13 SR20dets are all over everywhere and s14s have gained in popularity. The prices have come down as well. My 1998 s14s engine 3 years ago was around 3 grand delivered and it was a very good motor. Now you can get the same engine for around 2 grand delivered.

[jspaeth]

Originally Posted by corbin

The fastest KA-T's are in the 7 second range. They have more displacement, a stronger block, more torque, and better gear ratios than SR20's.

What? Last time I checked, an SR and KA tranny had the same gear ratios.....someone please correct me if I am wrong....

[jamanrr]

Originally Posted by jspaeth

What? Last time I checked, an SR and KA tranny had the same gear ratios.....someone please correct me if I am wrong....

they are the same except for 5th gear it is lower in USDM KA powered 240s than the SR20 counterpart.

[8Nismo9]

Originally Posted by corbin

Er, the SR is fourth and a KA is third, almost half a second quicker.

Besides, that SR is bored out to 2.4 liters. Such an extreme modification is hardly a fair comparison. Bore a KA out to 2.8 liters and see what happens.

2.6 to be correct,crower stoker kit my friend.

To the OP,if you thinking of SR then i don't see why not thinking of the KA

[drift freaq]

Originally Posted by Seanbonham

Drift,i'm sure i can search and find this out, but i figured it might be nice to get a free knowledge ride...do you know of what cooling stuff i need to keep my rb25 nice and cool? What fans fit, etc.

Preferably you run want to run dual FAL fans on a s14 you can actually sandwich them in between the motor and radiator while using a s14 radiator. You can run the S14 radiator in the s13 to try and do that as well.

If you go aftermarket radiator then you either run dual pushers or a push pull setup. Also especially on a s13 you need to maximize air flow.
The the stock zenki/chuki/Kouki fronts barely pass enough air when running a FMIC and the engine.

Either a Silvia front or S15 front will definitely improve the air flow, or a modified zenki/chuki/kouki front.

When I say modified, I mean heavily ducted for extra air flow with cutouts. You also want to seal the underside of the car with a underpanel.

From the lip of the front bumper back to your oil pan. As well as run a cooling panel up top. Its all about air flow and control of it.

[Ghost240]

Originally Posted by Seanbonham

I have read through the bazillion or so threads addressing this debate but i have a few other questions and none of the other threads really answered my query.

First, i can't even really find a post addressing this, but it seems that a lot of the motors coming from japan have been beaten to hell in terms of never having their oil changed. Is an rb25det LESS likely to have these problems/treatment than an sr20det cause it's a nicer car?

Anyway,

This fall i get a check for 10k on the button. I'm planning on swapping something into a 240sx, professionally, not myself (cause well, i'm not that good yet and i want AC)

Here is my goal/dilemma

It's a DD, so i need it to start, and ideally keep starting for at least...idk a year, preferably 2.

I want to hit low 12s in the 1/4 mile so that's at a minimum,

310+whp from the RB25det

or

290+whp from a RED TOP s13 SR20det (ideally 300, cause that's the magic number)

Here are my concerns/questions.

Redtop SR20det CONS/concerns:

290whp i know isn't pushing it for the sr20det stock internals IF you got a slightly bigger turbo, injectors, etc. you'd still be pushing out probably 14-17 (guessing) lbs of boost to reach that....that's a lot to ask for an engine to run everyday. IS that a lot?

SR20DET PROS:
Cheap parts, common, etc. shit we all know, ALSO, the s13 swap is simple enough that after i had it professionally done and all the parts in place, i'm more then capable of swapping in a new block if i blow it....so that's kind of nice.


RB25DET Cons/concerns:
Little bit more invasive a swap...that's a big engine, going to have to cut the fire wall etc...If something did break in the rb25, that's harder to find, harder to fix, more expensive. Not so confident i could swap in an rb25...probably could manage i guess....but still a more expensive motor. Biggest concern is really that... If i got an rb25 and something broke...i may be a whole shit more out of luck than if i had the s13. However, if the rb25 is a lot less likely to break...that's kind of worth the risk.

RB25det Pros:
It's a skyline..(had to say it), More importantly, it's a lot closer to that goal of 320 then the redtop is. You could probably put 300rwhp down with just a few bolt ons and stockish boost. Some have argued it's more reliable. Is it?


The most important thing here is reliability! That's what i want most.

Here's the place where i'd be getting the swap done, this is literally all they do pretty much. Both swaps would be the stage 2 for either, take a look at the parts list etc., and tell me what you guys think i should do for my goals.

I've owned both. I had an SR with a T28, FMIC, intake exhaust, blah blah blah....and tuned. It was fun. I wanted 300whp from it and while doing my research gave thought to putting an RB into my car. Looked between the 25 and 26 and chose the 25. And I will say I will never go back from having an RB.

Most RB owners problems stem from an unknown motor with unknown stress on it, hack job wiring, and etc. If you purchase a clip or swap complete do the basic maintence with the motor out of the vehicle. Get the wiring professional done by someone with a STRONG knowledge and understanding of the wiring. Take your time with the install of the motor and check out the conversion kits they offer.

It really boils down to preparation and being willing to pay the cost to do it right the FIRST time. Parts are readily available vie Rawbrokerage, Phase2motortrend and etc. So anyone that tells you, you will have to wait is full of it.

Personally, If i had to do it all over again. I wouldve built my RB from the get go. Then dropped in it. I guarantee you won't regret going RB if you do it right.

[Syncade]

Post above me is very accurate. Most RB owners are fanboys who do it incorrectly, then complain.

And OP, you sound like you haven't done enough research. Not bashing, I'm just saying. Measure twice cut once, aka, drop money now and enjoy later. If I can recommend anything, its these:

McKinney mounts
CarlH wiring
Shaftmasters driveshaft


Poof.

[Darius]

Agreed. RB>SR, but in the OP's case, he is only looking for 310+hp? The RB swap will cost considerably more than an SR swap and I'm only talking about parts. Wiring is a headache especially if you are unfamiliar with it and the various cooling and chassis coordination issues make it a real challenge.

In the OP's situation, I'd recommend going with an SR, no question. Get it done and get it on the track.

[jamanrr]

I did not think Sr vs RB threads were allowed any longer especially since there are hundreds archived on this board alone?


The 240sx aka Silvia never had the RB as an option and I assume that was for a reason. It was either SR20DET for JDM or KA24DE for USDM. I think people have less trouble with SRs because that was the engine that the car was meant to have and everything fits together like it should plus they are a good bargain as far as modifications go.

The only way I would have an RB is if I bought the Skyline to go along with it. Importing a true Skyline is not as a big deal as it once was and then you know the swap is perfect since it came from the factory that way.

[slideslidegnarslide]

an rb25 is 100 dollars more than an sr swap at our local importor rb you can dd with 400 wheel and it will still be reliable. rbs are built better imo an so what if the swaps harder to do your getting 10k handed to you do it right and youll never have a problem rb25 all day i wouldnt even think of anything else ohh and parts are every where dude aka zilvia every one on here knows where to find shit


AND I HAVE HAD BOTH SOO............ PLEASE DONT SAY IM JUST TALKING

[S14DB]

I don't see what hasn't been covered before in this thread.


Of course the thread results in flaming and fanboism.