Rb20 and 25 owners..

[scottymizt]

Oh and by the way, RB's are not bolt in. I can yank a KA, drop in an sr and have it reliably driving on the streets in a day. Can you do the same for an RB?

I prolly could did my sonoma in three days from start to finish. Honestly i dont wish i bought the rb25 for my sonoma im very happy with the 2l and it''s great on gas..... if i could keep my foot out of it. I averaged about 22mpg or so beating on it when i drove it "nice" i got 30-32mpg. Its VERY reliable since this engine is in my daily driver, thanks to many of die hards with rb's we are getting a bigger and bigger source for standard parts stateside. I think i have put about 6000 miles on my rb since it was installed and has been more reliable than my old gm 2.2l .

[rbsileighty]

You may try and deny it but anyone with an RB20 wishes they saved a little more and bought an RB25. Hell I wish I had waited a little longer and got an RB26... but the price jump is a hell of a lot more than $1300...

Not true... I've been doing this since 2001 and have had 20's with no intention on ever buying a 25. 25's are good motors, but I'd rather penny up and get a 26 if I were in the mood of spending more money on my core motor (kind of like you said).

I think the debate is fairly simple... what's your power goal and what's your budget. If you're shooting for 300-400whp range you'll always be ahead by however much money you saved buying the 20 over the 25 (don't forget the 20 is a direct swap for the KA since you don't need a new driveshaft and I don't know of to many people blowing up their 20's trans... just some more $ to the pile) since you can use the extra cash to buy parts like turbos, management, injectors etc... if you want 350+whp I'd go 26... doesn't have the ring problems you run into with 25's that have signif power gains (search and you'll see) and it's just an overall thoroughly engineered motor.

My friends car has a 25 and it's a great motor... but it came in the car he bought that was also loaded with Cusco coilovers, tomei 2way LSD etc... it was just a good buy... and I wouldn't say he should swap over to a 20... that would be stupid.

I was introduced to RB swaps back in 1999... was debating all of my options and decided on the 20 in 2002 due to Dan at JMS in Australia (not even sure if he's there anymore) telling me the above... I'll always be ahead with the 20 when compared to the 25 due to the cash difference.

It might not be common with people on this forum but there are a few 20's on this board with solid power curves... I actually went a diff route and used the money I saved and saved adding power for now... that's how I have CE28N's, Kei Office Coilovers, Stoptech brakes etc... so basically it's up to your goals and what you're looking for out of the car.

As far as the displacement argument... there are plenty of Evo's that are faster than STi's... just keep that in mind. You'll find in a lot of searches I like the 20/26 because of their racing history as well... no question I'm bias towards these over the 25 if you can't tell... but I do have some valid reasons if I do say so myself

Hope this helps bud! Won't hurt my feelings if you get a 25 btw (like it matters, ha)... it is a good motor in its own right


Modified by rbsileighty at 3:18 PM 5/14/2009

[Sil240]

I have a 20 and I like the 25 because of the parts availability.There seems to be more toys for the 25 then the 20. ITM and PFC but not much else.

But a SR is smaller & lighter and far more part availability than either. And less parts you have to buy (# of cyls).

I love the sound of my RB20 but if I had to do it again, I would have gone SR.I would have been driving my car 5 years ago.But now parts are cheaper, there's more info out there etc... (thanks to this forum)

Either way all of the engines I think you'd be happy with.Go with what your pocket will be happy with.It's all about driving your car and having fun with it.

[Dori-C-33]

Not really sure if this answer will help you considering im in Japan. My first car was an RB-20 DET C-33 Nissan Laurel. I had a few mods, front mount, HKS accuator, blah blah blah. It was a fast car and drifted with no problems. I did regular maintenance on the engine and had no problems. I estimate the HP at about 280.

I recently got a Nissan Laurel C-33 with an RB-25 DET. It has a highflow turbine, front mount, fuel pump, oil cooler, accuator, blah blah blah. I estimate the HP to be well over 300, and will I ever go back to an RB 20 ??? f*** no.. Im not saying that the 20 will not provide enough power to do what you want but if you can afford a 25 then I say go for it.

Basically same engine, but more power. But like I said im in Japan so its a little different for me. I payed $1300.00 for my whole car. What are your plans for the car? Drag, Drift? I would not suggest a 26 if you wanna build a drift car. I would take anything over an SR, but then again, I am an RB fan boy.

If you do get the 20, hit me up and i can overnight you some parts from Japan to make you faster....

[neonbomb]

OP

YOU =

[urcaptnspeaking]

OP

YOU =

I hope this is a Phucking joke. The people who know me on this forum know thats far from true. I do my own work. I build not buy.. my previous cars are tastefully modded, and I have a trans am and a fusion. Of course thats rice.. Noob.

[Uberck]

i was in the same position as you op. but it was between sr20 and rb20. the idea of a belted straight six 2 liter finally got to me though. the only thing im concerned when i do get around to dropping in the rb is the wiring. because in every youtube video and every forum thats where most guys have the trouble.

[urcaptnspeaking]

I have read only 4 wires are essential to making it run. The wiring wouldnt be hard if you identified the wires before hand. Instead of diving into it guessing. Diagrams for each wiring harness would be the best bet.

[rbsileighty]

Diagrams for each wiring harness would be the best bet.

That's the way I had to do it back in 2002... it's worth figuring out for yourself if you have the time... the more you understand the better

[urcaptnspeaking]

Agreed. If I end up going with one of these swaps I want to understand the wiring, just in case there is an issue.

[Carl H]

its not unusual for a properly installed rb20 to get high 20's mpg wise on the highway and some city driving...a friend of mine managed 28 quite frequently and only after we upgraded the injectors did it drop down to 27...and this was a car that was driven like it was stolen on a regular basis and the current owner is still on this forum and to my knowledge it still is out rocking out hard.I am a bit baised but it depends on what you want out of the car...the most fun i have ever had was my stock rb20 with handling mods in my s13.that being said for less than the toal cost of the install of a STOCK rb25 I can build an rb20 that will belt out 350hp and be reliable.its really all about what the end user wants, we cant tell you which is better...every engine has its merrits and deficits but remember the rb series was started off with the lowly rb20 which was then advanced into the rb26.there was a time when the gtr was beaten into submission by 5-600+ rb20 r31 cars.

[Carl H]

if you're gonna go rb25 then go for the neo...its pwnz the r33 rb25 in the face pretty effin hard and it rocks out like no other compared to a stock r33 rb25 stock for stock.

[urcaptnspeaking]

Oh yes, I watched/read numerous things about the neo. Solid motor. I would love to have it. By they are hard to come by. Other than the neo motor on ebay for I think 1500 ( as i mentioned before) but at that price... it seems sketchy.

[Bluefire]

I have a 20 and I like the 25 because of the parts availability.There seems to be more toys for the 25 then the 20. ITM and PFC but not much else.

But a SR is smaller & lighter and far more part availability than either. And less parts you have to buy (# of cyls).

I love the sound of my RB20 but if I had to do it again, I would have gone SR.I would have been driving my car 5 years ago.But now parts are cheaper, there's more info out there etc... (thanks to this forum)

Either way all of the engines I think you'd be happy with.Go with what your pocket will be happy with.It's all about driving your car and having fun with it.

Nailed it in the head!! Every single RB20 guy i've met had the same story. They didn't quite have the budget for an Rb25/26, and just could not bring themselves to go with an sr20. But because they had to have an RB they go with an Rb20. They end up spending a year trying to make it all work, and by the time its finally streetworthy, there getting there asses handed to them by a guy with an sr.

Comparing all aspects of a swap such as cost, ease of install, performance, parts availability, etc, the SR20 is undeniably the best choice.

But with the RB25 and RB26, you get a much higher HP potential. I really don't see where the RB20 shines in any category.

RB20's are to RB25/26's as CA18's are to SR20's. Or heres a better one RB20/RB25/RB26 : 56K/DSL/T1

[Bluefire]

For the comments on evo's beating sti's and RB20's beating RB26's, i don't really think this is a valid argument. Obviously any weaker engine or vehicle can be built to beat a stronger opponent with the right amount of money and engineering.

[scottymizt]

hey bluefire have you ever had an rb20? He is looking for first hand exp, if someone hasnt owned both engines then their opinion really doesnt mean anything. Right now the only thing that is holding my rb20 back from making the same or more power than my modded rb25 is the stock rb20 ecu.My truck weighs way more than any 240 probably ever will and even at 13psi on a t3/t4e turbo the truck makes me smile. I did have enough money to get an rb25 for my truck i just chose to go with the rb20. In my personal opinion the rb20 is well worth the money. I still plan to buy an rb26 as well for either my 67 1600 roadster or maybe swap into my 280zx. Then i will have all of em

[Kalypso]

ALL early RB engines suffered from the crank collar issue. Even into the R34 RB25 NEO had short collar issues in some cases.

Sub of a RB26 the R34 RB25 NEO is the motor of choice. But overall, for the price, ease, parts for a swap... the RB25 NEO is king IMO.

thank you! i didnt see this at first

we lucked out... the crank coller issue is rare on the 25s as far as i have experienced personaly and read.

even better

[Bluefire]

hey bluefire have you ever had an rb20? He is looking for first hand exp, if someone hasnt owned both engines then their opinion really doesnt mean anything. Right now the only thing that is holding my rb20 back from making the same or more power than my modded rb25 is the stock rb20 ecu.My truck weighs way more than any 240 probably ever will and even at 13psi on a t3/t4e turbo the truck makes me smile. I did have enough money to get an rb25 for my truck i just chose to go with the rb20. In my personal opinion the rb20 is well worth the money. I still plan to buy an rb26 as well for either my 67 1600 roadster or maybe swap into my 280zx. Then i will have all of em

No, i've never had an RB20. BUT I have installed, built, and driven a few for some customers. I was not impressed.

Also as I mentioned before any motor can be modded to make more power than another motor. That is a simple and obvious fact, which I do not deny. But in order to compare motors you have to compare multiple aspects and have some sort of equalizer.

Let's say we use cost as an equalizer, Can the average backyard mechanic build an RB20 to make as much power as an RB25 using the money he saved from purchasing an RB20? Possible, but not probable. I also emphasize backyard mechanic so no industry hookups on parts or tools and an average level of fabrication skills.

Now let's say you do manage to make as much power as an RB25 for the same amount of money. You maybe able to hit the same HP number, but your HP graph and TQ graph will definitely not match.

Now we bump the power goal to 500hp. So again can the average backyard mechanic build an RB20 to make 500hp with the same amount of money it takes an RB25 to make 500hp? And again i'll admit possible, but HIGHLY improbable. Also as the power level increases, so does the gap in hp and torque graphs. Transmission reliability for the RB20 will also be way down. Any hards shifts at this point will destroy stock RB20 gears.

And finally since I know someone will say it. If you only want 350 to 400hp out of the motor, you picked the wrong engine. As mentioned before, the RB's strongest advantage is its power potential. If you don't intend on pushing your RB to higher hp numbers then you should have gone with an SR20. The whole indestructible iron 6 cylinder advantage goes out the window and actually becomes a disadvantage at that power level because of the weight aspect.

Honestly in the whole cost vs performance, best bang for the buck, category, I personally feel the RB20 ranks low. Aside from the Naturally Aspirated RB idea someone threw out awhile ago, which takes the crown for worst cost vs performance. Also i'm probably just an RB20 hater.

[scottymizt]

how modded were the rb20's you installed and driven? I do agree that with the stock turbo the rb20 is not even close to the rb25. With a turbo upgrade(mine is a cheap 150 dollar ebay turbo...dont laugh ) the rb20 with low boost will run very well, even better at higher boost. I can keep right up with my buddy running an rb25 in his z31 with higher boost on the stock turbo. As stated above my truck weighs 3600 lbs which is considerably more than the z31. The turbo on the rb20 is the down fall of the engine as far as stock goes, doesnt flow well at high rpm and cant be turned up over 14psi due to turbine falure. Its obvious the HP and TQ curves wont be the same from rb20 to 25 and even 25 to 26. Its like saying well the rb26 is junk because the rb30 makes more TQ and HP. The only reason i would get an rb26 would be basically to say i have them all, If i was looking for killer power i would just build another rb30 Honestly in my personal opinion no one should be putting any engine in their car in the back yard There are a ton of haters of all engines and until someone actually has one and gets to drive it in every plausable situation it not really fair to hate on it. I had the stock 2.2l in my sonoma and it was a turd but with a little turbo work that engine became fun!! tons of people hated on it saying that it wont handle much boost, i was using the same turbo that is on my rb now and boosting 12psi. I had a coolant leak along with an oil leak and had to replace the head gasket because the head bolts came loose . Come to find out it came loose long ago and i never thought to check. anyway after taking the head off of this 170k mile engine the cross hatching was still in the cyl walls and it looked pretty much new. i still have the engine on the floor of my garage and plan to use it in some kind of project. I really dont hate on any engine every one has some aspect that is better than another, including of just sucking

oh and on a side note that ebay turbo has about 12k miles and two engines under it's belt and still running strong. I beat the crap out of both the 2.2l and the rb20 every day. With any of the engines there is always someone who will buy it if you decide you dont like it.

[Sil240]

If you don't have a lot of $$ go KA-T or SR.If you don't have a little bit of $ go with a RB20If you have a decent amount of $$ go with the RB25If you are a Baller go with a RB26If your a SUPA BALLER build a Rb30

[Kalypso]

and if you have a medium amount of $ and your smart go with

twin turbo holset LQ4 for the WIN

[urcaptnspeaking]

Haha. I am up in the air guys. I dont hate on motors either. Because all the motors that are typically swapped in these cars are good motors, and have tons of potential.. thats why I am stuck.

[foCk]

I started with a 20 and upgraded to a 25

In the end I miss the 20's power curve and how eager it is to rev high... but the torque from the 25 makes up for it..

IMO do what you can within your budget to get your car reliable then if that's not enough, you can always upgrade. It doesn't matter if you have a RB30 if you cant drive the piss outta it and not worry

[Kalypso]

twin turbo LQ!!

...for the win

[yotik]

i would say rb20/sr20 over rb25. And 26 pwns all the others. for less than the price of rb25 install you could have rb20/sr20 in. you could make up a lot of the power difference with the $$ you save. imo if youre gonna go baller cut teh crap and get the 26.

right now im doing a rb20 into s13 (check sig). im doing it pretty much by myself and ive been able to find all the parts i need etc. For me the rb20 was the best option cause im only looking for 300 hp to start (rookie power).

as far as the lies ive heard on here dont believe it. aside from wiring, the rb20 is a direct bolt in if you buy the right parts. i havent fabbed anything and its installed and cranking. i bought my parts as i went along and everything has fit like stock (r32 xmember, auto ka transmission xmember blah blah), hood closes dump pipe just barely clears everything fits. if you want to join the rb club but are broke like me just go rb20det. ive seen em as low as $1100.

[DrifterProdigy85]

I got my R33 RB25 motorset for $1650. Im not gonna complain. Also i love the extra tq of the bigger engine.

[Kalypso]

I never imagined this thread would swell to be so big...

everyone had a lot to get off there chest

[urcaptnspeaking]

I never imagined this thread would swell to be so big...

everyone had a lot to get off there chest

see and some dude tried to flame me...

but really i didnt think so either.

[Kalypso]

every few months the debate needs to erupt again.

the first 4 posts always has someone who doubt the relevance of a thread.

[S14-NEO]

+1 on the NEO RB25...have had it for three years now almost and its making some pretty serious power with no issues whatsoever thus far...(MINUS transmission ISSUES)...lol...but that is being rectified right now..WOOT!!