# RB vs. SR20



## nosdelux (Dec 8, 2004)

Can neone tell me what the advantages of these motors are over each other....recently alot of people have been leading me towards the rb....but im not sure how that motor is....can neone help me out?


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## jeong (Jul 22, 2004)

*sigh* search -.-;;


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## zellx2004 (Sep 30, 2004)

jeong said:


> *sigh* search -.-;;


HAHAHA. 

RB is an iron block inline 6

SR is an aluminum block 4 cyl. 

Both can be turboed and both are JDM. go to www.Phase2motortrend.com


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## S14240SR (Aug 20, 2004)

nosdelux said:


> Can neone tell me what the advantages of these motors are over each other....recently alot of people have been leading me towards the rb....but im not sure how that motor is....can neone help me out?


I wanted to get a RB25, but parts are expensive, hard to get, and the handling and weight balance of the 240 is affected by the RB. It weighs about 180lbs more than the sr20/ka24. If you do decide to get an RB25/26, I suggest that you upgrade your brake system before or soon after the swap. 180 extra lbs under the hood + alot more torque and power+small brakes=disaster.


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## Irishweird00 (Nov 16, 2004)

S14240SR said:


> I wanted to get a RB25, but parts are expensive, hard to get, and the handling and weight balance of the 240 is affected by the RB. It weighs about 180lbs more than the sr20/ka24. If you do decide to get an RB25/26, I suggest that you upgrade your brake system before or soon after the swap. 180 extra lbs under the hood + alot more torque and power+small brakes=disaster.



Still wondering why people are afraid to put an RB in a 240 because it weighs 180lbs more.... it's like having someone sit on your dash when you drive. or a passenger in the car. it's only 180lbs... the car weighs 2700lbs, it's not going to affect the balance that much


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## S14240SR (Aug 20, 2004)

Irishweird00 said:


> Still wondering why people are afraid to put an RB in a 240 because it weighs 180lbs more.... it's like having someone sit on your dash when you drive. or a passenger in the car. it's only 180lbs... the car weighs 2700lbs, it's not going to affect the balance that much


I never said how much the RB25 would affect handling, but just getting the rb25 in would barely fit my budget. If you want the rb25 to have the cleanest fit with no clearance problems www.mckinneymotorsports.com has rb25/26 swap kits with crossmembers and driveshaft for $1150. Ive heard of RB25 powered 240s winning drift and other competitions, but good parts are still complicated to get and require overseas shipping charges. Taka Kaira motorsports in Japan has tons of aftermarket parts for the RB20/25/26 http://www.rb25det.org/ As for oil filters and things like that im not sure, but parts might be interchangable with some usdm nissans/infinitis


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## jeong (Jul 22, 2004)

S14240SR said:


> I wanted to get a RB25, but parts are expensive, hard to get


not true anymore (part cost went down, front clip/motorset prices went up)


> and the handling and weight balance of the 240 is affected by the RB. It weighs about 180lbs more than the sr20/ka24.


ask all S-chassis owners that has a RB under the hood. ask them if they have noticed any difference in handling. unless they are professional drivers (who can tell how air is in each tire with one turn), they will not notice any difference in handling. as Irishweird00 said, it's just like having a passenger, no big deal. after you get the car running after a swap, you should focus on suspension/brakes before turning up the boost or getting a bigger turbo. of course that's just a "recommendation"

rb25's can be swapped w/o using custom mounts. rb26's, however must use custom mounts because usdm 240's are LHD. steering column gets in way of the two turbos (either use mckinny/custom mounts or go RHD)

fyi. dont get parts from taka kaira..they rape you on prices


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## zellx2004 (Sep 30, 2004)

Irishweird00 said:


> Still wondering why people are afraid to put an RB in a 240 because it weighs 180lbs more.... it's like having someone sit on your dash when you drive. or a passenger in the car. it's only 180lbs... the car weighs 2700lbs, it's not going to affect the balance that much



That is BULLSH*T!


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## jeong (Jul 22, 2004)

you just beat it out of me..

shut up noob

honestly, if you're so goddamn worried about "oh so holy perfet weight ratio that is needed for drifting", throw 180lbs worth of sandbags in ur trunk. choosing a sr/ca over a rb to keep the "weight ratio" is simply retarded


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## lyon23 (May 1, 2004)

jeong said:


> not true anymore (part cost went down, front clip/motorset prices went up)
> 
> ask all S-chassis owners that has a RB under the hood. ask them if they have noticed any difference in handling. unless they are professional drivers (who can tell how air is in each tire with one turn), they will not notice any difference in handling. as Irishweird00 said, it's just like having a passenger, no big deal. after you get the car running after a swap, you should focus on suspension/brakes before turning up the boost or getting a bigger turbo. of course that's just a "recommendation"
> 
> ...


I agree with jeong and I do have an rb20 in my 240 and I cant tell the diference in handling.. Its got a lot of roque and power and then only change I would do is go with an RB25 but just the engine, harness and ecu so I wont change the tranny and have to spend money on a driveshaft.but as it is I love it still have to upgrade it with bigger turbo and injectors..and parts for a both are available now more than ever...as far as the weight night did the comarison and the this is how the sr ka and rb weight out sr40lbs<ka<rb25 60lbs.. so the sr is 40 lbs less than the ka and the rb25 is 60lbs more than the ka and the rb20 is about 30pounds less than the rb25... so if you are scared of having a big engine in your car don't say bad things about it untill you try it. right now I'm working on a sr20 swap on another 240 then I can actually be one to say that one is better than the other or where one lacks something the other makes up in something else. I'm not trying to start a fight but who knows maybe after I drive the sr I could change my mind but will see.


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## lyon23 (May 1, 2004)

I weight my car (95 240sx with rb20)and with a half tank of gas is 3000lbs on the dot. with me on it it was 3196.


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## mille-16i (Jun 16, 2004)

nosdelux said:


> Can neone tell me what the advantages of these motors are over each other....recently alot of people have been leading me towards the rb....but im not sure how that motor is....can neone help me out?


We are just alittle off subject. What are the pros and cons to each when used in a 240 and who gives a hoot about the weight ratio ( yes a perfect 50/50 is desirable) lets answer the question


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## S14240SR (Aug 20, 2004)

nosdelux said:


> Can neone tell me what the advantages of these motors are over each other....recently alot of people have been leading me towards the rb....but im not sure how that motor is....can neone help me out?


true, im laughing at how were arguing at each other and still never answered "nosdelux's" question. Heres a site with specs and swap info on the RB25 http://www.rb25det.org/ for the sr20det www.srownersclub.com (heavythrottle) and http://www.xatracing.com/xatracingparts.html?row2col1=nissanengine.html has good info on them


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## jeong (Jul 22, 2004)

i'll compare rb20 to sr20 (same displacement)

- rb engines are iron, sr engines are aluminum (rb engines can handle more power in stock form) rb's weigh a little more but as mentioned above, weight difference is negligible
- rb engines are inline 6, sr engines are inline 4
- rb20/25det have t3 turbo flanges, sr20 has t25/28 turbo flanges
- rb20det has 270cc injectors (max out at ~320hp), sr20det has 320cc injectors (max out at ~320hp) ~hp=(injector flow x number of injectors)/5
- rb20 and sr20 both produce about 205hp


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## OPIUM (Aug 18, 2002)

The only difference besides the obvious is YOUR preference. Go with what you know and succeed with that. The RB20 isn't the greatest motor of all time, and neither is the SR20. Each has its own quirks, and power delivery. One is easier to wire in than the other. Both are direct bolt-ins. Both will give you that happy grin that you desire in stock form. And both will smoke most civics out there if thats what your worried about. Difficulty getting parts for the RB vs. the SR is just a scapegoat and is getting easier and easier to find parts for it everyday. That should no longer be a major concern to anyone. However I feel that the RB is a more potent motor having owned both. If you know of a nearby shop that does SR swaps, then they will be able to figure out an RB if they don't know how to wire it up already. In the end its all just preference


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## kaptainkrollio (Jul 29, 2003)

Kind of OT, but it's the 300zx NA clutch that fits the RB20, right?


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## nosdelux (Dec 8, 2004)

Alrite Guys thanx for alll the info about the motors...it was prety helpful...i think im prolly gonna go with th RB25 but ill do a little more research...ill ask u guys more often...cuz i only am 16 and tryin to do this stuff by myself...lol...but i do go to school for automotive as well as regular school...so hopefully between u guyz and school ill get this swap done good...ill keep yall posted....thanx!


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## S14240SR (Aug 20, 2004)

kaptainkrollio said:


> Kind of OT, but it's the 300zx NA clutch that fits the RB20, right?


Yes, and the RB25 also


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## lyon23 (May 1, 2004)

nosdelux said:


> Alrite Guys thanx for alll the info about the motors...it was prety helpful...i think im prolly gonna go with th RB25 but ill do a little more research...ill ask u guys more often...cuz i only am 16 and tryin to do this stuff by myself...lol...but i do go to school for automotive as well as regular school...so hopefully between u guyz and school ill get this swap done good...ill keep yall posted....thanx!



my advice to you is get a 240 learn to drive it and control it and then do the upgrade after a couple of years of practice driving and learnign the car...I'm not trying to jinx you, discourage you, insult your driving abilities or nothing like that... but a lot of people just want to go so fast and can't handle it and get into trouble and hurt thenselves or someone else.. so learn now and have fun later.


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## nosdelux (Dec 8, 2004)

lyon23 said:


> my advice to you is get a 240 learn to drive it and control it and then do the upgrade after a couple of years of practice driving and learnign the car...I'm not trying to jinx you, discourage you, insult your driving abilities or nothing like that... but a lot of people just want to go so fast and can't handle it and get into trouble and hurt thenselves or someone else.. so learn now and have fun later.


thanx for the advice...im plannin on tkakin my time in the project...buildin up the motor from the bottom up and doin a good job...im not so worried about goin fast right now...i have just always been into tuning motors and all ever since i first saw it...and i do wanna be able to do shows and i wanna be ableto know i have that power under my foot if i need it...lol...but no im not worried about just goin crazy with it right now...it is a fun car to drive and i have some more to learn about it so hopefully once the engine is done i will have the ability to drive it like it should be driven...thanx


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