RB20 vs. SR

Post by **perpetual gyro** » Wed Jan 15, 2003 6:28 pm

I haven't seen a thread comparing these two motors so i thought i'd post one. Taking cost, power, and performance into consideration, what would you guys prefer?

I ask this because it seems to me like the RB20 slightly out performs the SR and it's basically the same price...so what's so special about the SR that everyone has one? hype maybe?

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

Why? Its A 2.0 Vs a 2.0?The RB20 in a 240 not going to out perform a SR20 IMO, I love the RB20 but in cars that were designed to have them... An RB25 or 26 is worth the trouble to put into a 240. They both have their downfalls. look around on the forum and do some research:D

Post by **perpetual gyro** » Wed Jan 15, 2003 6:28 pm

YamaOni wrote:Why? Its A 2.0 Vs a 2.0?The RB20 in a 240 not going to out perform a SR20 IMO, I love the RB20 but in cars that were designed to have them... An RB25 or 26 is worth the trouble to put into a 240. They both have their downfalls. look around on the forum and do some research:D

I have done research in this area. I realize their both the same displacement but you also got 2 more pistons, plus it's much cheaper (w/ clip) than the highly-demand SR. And as night pointed out, it's only about 100lbs heavier, and has [roughly] 35 more hp at the wheels...so please explain why you would choose the SR over the RB instead of just spitting out opinions. Thanks.

Quote »The RB20DET has less stock torque than the SR which is a downside[/quote]Hey night,really? I would of thought that the RB had more torque. Can you please explain to me why? Thanks bro.

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

First off I am assuming things like you are in the states and are doing this to a S13 body style 240.....Why I would go with a SR rather then an RB20,The SR 20 is for the most part a drop in with little bs while the rb needs a some more cutting and splicing to make it fit, If you have the time and the money to do it go for it. The SR has a better parts availability then the RB in the states both stock and aftermarket. If state side companies complain on having trouble finding parts like igniters, coil pack sand MAFs for the SR what happens if your need an coil pack for the RB? In the end the RB20 is a good engine but so is the SR. Why not hold off and get a 25 or 26, they cost more but in the long run it would be worth it IMO.

Also I have seen more the one RB car (R32,A31,C33) swapped over to SR, it saves weight and any time you can drop the power to weight ratio in your favor its a good move:D

Post by **themadscientist** » Wed Jan 15, 2003 6:28 pm

Go SR, the RB20 is a great engine but not worth the trouble of forcing it into a 240. An RB25 or 26 makes enough power over the CA and SR to make it worth the extra trouble. I can get an RB20 for $100.00 and it isn't worth it to me, that should give you some indication.

Post by **perpetual gyro** » Wed Jan 15, 2003 6:28 pm

hey yama,thanks for explaining your reasons. To answer your assumptions, no, I'm swapping into an s14 body, not s13. And yes i'm in the states. As for part availability, that was really what I was concerned about, but my friend at unstable hybrids said they'd help me get any parts i would need if future problems arise. And about the installation, they would only charge me another $100 for the RB swap. So parts and ease of installation aside, it seems the only real difference is 2 extra pistons and another 100lbs or so. Considering the front clip is about $1,000 cheaper, kind of makes you wonder why everyone chooses the SR over the RB.

prof,I would like to go with an RB25, but money is a huge problem for me, considering i'm a broke *** college student. I'll have plenty of time to upgrade later on down the line. For now though, I would certainly be happy with either an SR or RB. So you can get an RB for $100? Care to make some money?

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

In the long run that $1000 does not add up, You need two more pistons, con rods and so on. Good luck:D

Post by **WDRacing** » Wed Jan 15, 2003 6:28 pm

As long as you don't use the CA both the RB20 and Sr are cool...hehe.

But really, I've built RB20's for the last few years. If I were in the states, I'd go SR....... and I hate SR. But the RB20 just isn't worth it. Rb25 or 26 like the guys said, hell yeah.

WD

Post by **themadscientist** » Wed Jan 15, 2003 6:28 pm

I live in Japan, that's how I can get the RB so cheap. Take into account pulling it, cleaning it, packing it, shipping it, trucking it, and misc you will pay the same as if you got it from a pro operation. IMO if you are in fact a humble broke guy then I would suggest you hold off on the engine swap for now. If you know you will be folding bank in the future why not take this time to set up the suspension, beef up the unibody, get you fuel and cooling system upgraded so when you are ready to get an RB your bank will be ready and your car will be ready and you can get a big 26.

Post by **perpetual gyro** » Wed Jan 15, 2003 6:28 pm

so is Knight right in that the RB has less torque than the SR? thanks.

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

The RB20 has 27.0 kg at 3200 rpm as for the SR dont know:D

Post by **Red Lightning** » Wed Jan 15, 2003 6:28 pm

I think it depends on how much hp you're shooting for. If you want 300whp, go SR, you dont need a rebuilt, just fuel and turbo upgrade. But if you're going for 400whp or so, you're going to need to upgrade internal one th SR anyway, get the RB25DET, nightXCZ777 sell the clip for $3000, and 1000 for install, you dont need new internals on the RB, just fuel and turbo. IF I'm shooting for more that 260whp, I would go RB route.

Post by **meggala** » Wed Jan 15, 2003 6:28 pm

the one thing going for the rb 20 compared to the sr is the exhaust note you have to hear one to understand.here is a sm~~~ vid of me getting slaughtered by a gtrhttp://www.meggala.com/mydrag.htmmeggala

Post by **Nif** » Wed Jan 15, 2003 6:28 pm

ahh the sweet sound of the rb. I'm a little misty right now, it bring tears of joy to my face. Just to let eveybody know the note of the rb is very similar to the note of the LeMans prototype v-12 BMW which may mean nothing to a lot of people but hey the sound is absolutely glorious.:icesangel

Post by **themadscientist** » Wed Jan 15, 2003 6:28 pm

yeah, the RB does have a "sound", just like the old Ls, it is umm, arousing.

Post by **cosmo** » Wed Jan 15, 2003 6:28 pm

I think the RB would be a better choice for an SR for any power aplication. If you're cheap the RB20 would work, but the RB25 seems more woth it in the long run.

Or if you're really cheap, go RB20, 3" in exhaust, filter, FMIC, then boost the hell out of it and maybe even throw a small hit of nitrous on it, like 35-50. That should be good for near 275 whp maybe more.

BTW.....What is a good front mount for the RB20? I haven't seen any places that have them.

Post by **WDRacing** » Wed Jan 15, 2003 6:28 pm

The RB20 will make 300hp without any N20 there Cozmo...

400hp seems to be the point where things start getting real expensive.

WD

Post by **cosmo** » Wed Jan 15, 2003 6:28 pm

got any websites?

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

NightXCZ77 wrote:Very true, 400 HP is what I have heard from many people on the RB20DET engines. I can get a decent front moutn intercooler kit for the RB20DET engine. I know of atleast 3 companies I can get them from that make the kits.

Night

On a fully rebuilt engine but for how long?It can be accomplished but the price dumped in to do it is almost not worth it. An example, My friend had an R32 RB20 that had been worked, new everything tomai pistons cams valve springs and for the past year had been running an IHI RX6 turbo. He was pretty happy but wanted more power, so he wanted to go from 2.2 to a 2.4. He garbed an RB26 crank and took it to the shop and they ripped the motor apart and of the cylinders had scratches in it. The owner said it wont cost much more to go 25or 26. Guess who won the battle? The 26 that has been worked up to 2.7 and has some other good stuff. A little more money but well spent.In the end the 20 is a good engine but its like motorex selling R32 GTS skylines....Why?

Post by **themadscientist** » Wed Jan 15, 2003 6:28 pm

I saw you dreaming about that $18,000.00 GTS-T Motorex was offerin last night ONI don't BS.

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

No master it was just a GTS:D

Post by **meggala** » Wed Jan 15, 2003 6:28 pm

I regret not putting an 25 in my r32 when I had the chance long story but for a big build up its the way to go if your happy with 300-350 the 20 is the go but over that the 25/26 are a better option . I whimped out an jsut put an rb25 turbo on my rb 20 cooler an exhaust. I'm waiting for my new toy to arrive then the fun will begin. yeah the new toy is an ex drifter cefiro hoping to get 400 hp or so from the rb 20 in it we will see.meggala

should be arriving next month

Post by **WDRacing** » Wed Jan 15, 2003 6:28 pm

YamaOni wrote:On a fully rebuilt engine but for how long?It can be accomplished but the price dumped in to do it is almost not worth it. An example, My friend had an R32 RB20 that had been worked, new everything tomai pistons cams valve springs and for the past year had been running an IHI RX6 turbo. He was pretty happy but wanted more power, so he wanted to go from 2.2 to a 2.4. He garbed an RB26 crank and took it to the shop and they ripped the motor apart and of the cylinders had scratches in it. The owner said it wont cost much more to go 25or 26. Guess who won the battle? The 26 that has been worked up to 2.7 and has some other good stuff. A little more money but well spent.In the end the 20 is a good engine but its like motorex selling R32 GTS skylines....Why?

RB20DET with alcohol injection = lots of boost with no detonation. Alky injection is only 350 bucks.

Not that I'm reversing my opinion stated earlier, the 25 is still the way to go.

But the 20 will make a decent 400 or very close without getting to expensive.

WD

Post by **cosmo** » Wed Jan 15, 2003 6:28 pm

yeah 300-350 is pretty much my power goals. I'm not goin for some massive power monster that's a ***** to drive on a daily basis, since this is gonna be a daily driver. And as cheaply as possible so I got money left over for suspension, brakes, all that.

Also.....I know you need lines to be fabricated to keep A/C but what about the heater? Will that still work? Since I live in Iowa i might need that.

Post by **perpetual gyro** » Wed Jan 15, 2003 6:28 pm

ok good..i was wondering about that too...so i'm not going to run into any surpises then when i get my RB swap, like losing power steering or some odd ball thing. Just gotta make sure.

Post by **YamaOni** » Wed Jan 15, 2003 6:28 pm

WDRacing wrote:RB20DET with alcohol injection = lots of boost with no detonation. Alky injection is only 350 bucks.

Not that I'm reversing my opinion stated earlier, the 25 is still the way to go.

But the 20 will make a decent 400 or very close without getting to expensive.

WD

I believe it can come close but 400 is not as easy as lots of boost and alcohol. Booze is not the answer:icesangel

Post by **BB Turbo** » Wed Jan 15, 2003 6:28 pm

All of this engine talk is getting me sleepy, I have learned allot from this thread. Must..........stay.............awake.

Post by **SonicS14** » Wed Jan 15, 2003 6:28 pm

whats the best place to buy an RB20 in terms of price and quality? and what exactly needs to be fabricated in order to install?

Post by **themadscientist** » Wed Jan 15, 2003 6:28 pm

hit up dauntless, he does that sort of thing.

Post by **rbsileighty** » Wed Jan 15, 2003 6:28 pm

NightXCZ77 wrote:The RB20DET has 194 pounds of torque. I am not sure why it is lower than the SR, Nissan would be the company to ask for that one.

Well... the reason is that the SR has an 86mm stroke and the RB has a 69.7mm stroke. What this translates to is the SR has greater rotational inertia than the RB does. Torque for cars is basically the amount of force exerted tangent (on the edge) the crankshaft which is, in basic concepts, a circle. What this does is create a moment about a circle (a torque) causing the crankshaft to rotate. A moment is defined as M= perpendicular force X the radius between the force and where the moment occurs (in this case stroke).

Therefore, you can see that as the stroke increases so does the torque (moment) about the center of the crankshaft. Considering all else equal (both 2L motors with equal rotational parts mass), this is the main reason the SR has more torque than the RB.

Hope this helped!Sig

RB20 vs. SR

RB20 vs. SR

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