RB25DET or red top sr20DET

Post by **IceRock** » Sat Sep 13, 2003 7:24 pm

Whats better? an RB25DET or red top? whats the difference between the two?:ylsuper

Post by **vwluv10338** » Sat Sep 13, 2003 7:24 pm

One is a 4 cycl. and one is a 6, other than that they are identical:D

Post by **MainEvent212** » Sat Sep 13, 2003 7:24 pm

more displacement...umm...i think the RB series is Iron/block Aluminum head

and the SR is aluminum block/head

Post by **K240** » Sat Sep 13, 2003 7:24 pm

The Rb25det is better due to being a 6cylinder.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

welcome to NICO, i hope u find everyone here very helpful and informative, but i must say, please search first (red button at top of page) as this is a pretty broad question, but ill do my best. First off, they are two totally different motors:SR2odet : 2.o liter inline 4cyl aluminum block and head DOHC 2o5hp and 2o2ft lbs of tq roughly(used in many cars ,but mostly associated with the late model 18osx's and silvias)

RB25det: 2.5 liter inline 6 cyl. Iron block, aluminum head 25oHP and 225 ft lbs of tq roughly (used in Skyline GTS-Ts) they are completey different than any SR2o (diff cams, stroke, block, head everything is different)as far as better, thats basically a matter of opinion and what you want to use the car for. If you want a drift car, u dont need gobs of power, and the sr would do just fine, however if u want the most power out of your 24o, right now the rb25 is the way to go (unless you can afford the 26)

Post by **IceRock** » Sat Sep 13, 2003 7:24 pm

thanks

Post by **pstickne** » Sat Sep 13, 2003 7:24 pm

The number of cylinders isn't a critical issue (although, in this case--2L I4 vs. 2.5L I6, it does mean that each cylinder in the RB is smaller).

Advertising for the SR20DET? You decide.In fact, more cylinders = more injectors, more plugs, more wires = more money. (More $$$ = better?)Meggala (forgive me if I mispelled your handle :-) even transplanted a SR20DET into a late-model Skyline.

Compare a RB20DET and an SR20DET. Roughly the same figures as far are power goes. Actually better in the case of the S15 SR20DET (~250HP), but it makes the higher HP with a higher-RPM powerband (think of a Honda engine...)

The displacement on the other hand, helps ALOT.More displacement (assuming the same RPM) = more air moved through (on the same amount of boost) = more fuel burned = more power.

Don't forget, adding boost = adding heat = increasing chance of pre-detonation = ohh, ****!This is why you don't see [many] 2-bar boost cars even though the internals might be able to handle it. It's a diminishing pay-off. Of course, decreasing the "sensitivity" of the gas... but this is getting off-subject, no?

In addition, the RB series engines were designed better. Period. Hence they are (or rather, were... meet the new "V35" Skyline) used in the JDM Nissan flagship, the oft praised Skyline (R32-34).

Another important note are "Neo Straight Six" engines: later RB25's (R34, late R33?) had VVL and were rated at 280HP--up from 250HP.

The RB26DETT went into the top late-Skyline models and is VERY conservatively rated at 280HP as it is factory de-tuned.Of course, price, fitment issues and increased TT complexity are a negative.

There is plently of other information, but this is what "search" and "google" and *gasp* "research" help you with...

Post by **pstickne** » Sat Sep 13, 2003 7:24 pm

Personally, given each approach cost the same (and they are really close--mainly because of the stupid premium markup the SR20DET carries), I would choose a RB25DET over a SR20DET in the blink of an eye... you can get custom motor mount kits and everything these days.

You also have to take into account what you want your goals to be. I'd be happy with 250+rwhp in a very treetable setup.

But so much to do first...

Post by **JESTER** » Sat Sep 13, 2003 7:24 pm

Welcome to NICO. It looks like nlzmo400r took care of the answer.

RB25 would be pretty cool. You can make more power with less work and money. But it will cost you more money to buy the RB and get it installed. There are a few members that are running on RB power. Must be nice.

The SR is good, for price and ease of install.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

pstickne's got you covered bro, there are other very specific spec of each car (such as compression and what not) but that doesnt really matter in this sake of comparo

Post by **jacob360** » Sat Sep 13, 2003 7:24 pm

The 240sx chassis was built around the SR. It has great weight balance.

The RB adds alot of weight. A good amount of it comes from the stouter transmission, placing it in the middle of the car, but the engine is much heavier too, and because of the length, much of the weight is placed in front of the front suspension.

If you're looking for a killer drag car, go with an RB. If you want a car that handles well (which is one of the main reasons for going with a 240) and also has potential for good power, go SR.

Or you could always just turbo the KA.

No offense to you IceRock, but I knew this would start happening once that article came out in SCC.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

yea, i was thinking the same thing jacob, when i saw that rticle, i expected it to happen, but the RB is a heavier motor than the SR, but the power difference will make up for it if u know how to adjust to the weight difference. Another option is hte ca18det, its got great potential for power as well, and doesnt weigh much, however i think its an iron block, which is good for high boost, but not great for weight. The KA is a great motor, and since drifting has become so big, everyone wants an SR or RB (more so the SR). But the KA has .4 liters on the SR, and only loses .1 liters on the RB (25 that is) but has an iron block that the SR doesnt have.

Post by **SWIFT_DRIFT** » Sat Sep 13, 2003 7:24 pm

jacob360 wrote:The 240sx chassis was built around the SR. It has great weight balance.

Lol. Funny because all the S chassis started with the CA...

The KA is a great motor, and since drifting has become so big, everyone wants an SR or RB (more so the SR). But the KA has .4 liters on the SR, and only loses .1 liters on the RB (25 that is) but has an iron block that the SR doesnt have.

Wow you have basic math skills, congrats...you still don't know what you are talking about though, sorry.

Post by **93semax** » Sat Sep 13, 2003 7:24 pm

SWIFT_DRIFT wrote:Lol. Funny because all the S chassis started with the CA...

When and where did the s14 and s15 have a CA?..

Post by **SWIFT_DRIFT** » Sat Sep 13, 2003 7:24 pm

93semax wrote:When and where did the s14 and s15 have a CA?..

Where did the s14 and s15 get their heritage from noob. Or we could get even more technical since I was so general in my previous post. The s13 started it's life with the Ca, not until 90.5 was the SR introduced. Damn even take a look back at the s12's and earlier, no sr's there either. There would be no s14 or 15 without that. The sr is just another motor in a long line of good motors.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

SWIFT_DRIFT wrote:Where did the s14 and s15 get their heritage from noob. Or we could get even more technical since I was so general in my previous post. The s13 started it's life with the Ca, not until 90.5 was the SR introduced. Damn even take a look back at the s12's and earlier, no sr's there either. There would be no s14 or 15 without that. The sr is just another motor in a long line of good motors.

funny you're changing what you previously said: 'all S chassis started with the CA', which ISNT true, so dont try to flame others, got it? And in all actuality, yes i do have basica math skills, and i know EXACTLY what im talking about, thanks for all of your professional help which u say eagerly displayed for the new guy, we couldnt have done it without your childlike flaming :rolleyes ...***

Post by **SWIFT_DRIFT** » Sat Sep 13, 2003 7:24 pm

Or we could get even more technical since I was so general in my previous post.

Sure, I'll quote myself for you. I don't really see how I'm suddenly changing what I originally said, just modifying upon it for people who have no idea what s12's even are.

And in all actuality, yes i do have basica math skills, and i know EXACTLY what im talking about,

Yeah I know you have basic math skills, I even said it myself. You obviously don't have "basica" grammatical skills or you could read my posts and reply in normal punctuated English. Oh, you suddenly know exactly what you are talking about? This is coming from the same kid who couldn't even find the clutch master cylinder on his friend's 240. Rofl.

Dude spending all day reading about motors and memorizing numbers means absolutely nothing. Cars are a hands on type of deal. Go take your car apart, put it back together and see if it works properly again. If it does, then I will congratulate you and give you a cookie.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

funny you should mention that thread. The one posting was a frined of mine (the owner of the 24o). When his clutch gave, and he went to check the fluid, he couldnt find the cylinder and couldnt contact me. So he came here thinking he could find answers and just used my name. I was actually the one who saw him hte next day and pointed it out. He had seen it, but wanted to be postive and all of the dirt on top of the cap didnt help him too much, but hey, everyone learns from somewhere. I know damn well u didnt start out knowing everything about everything. Abd as far as reading about motors and memorizing numbers meaning nothing, B.S, reading is the biggest learning tool you'll find if you can't do the hands on stuff. And besides bhy reading, you can learn from others mistatkes so u dont make the same ones yourself. And as far as taking my car apart, no need , i have a warranty as of now, nad if i did have a prolblem and no warranty, i could do whatever i needed myself (for the most part anyway) and if i couldnt, i make enough money to where i dont' have to. O i apologize about my grammatical erros, but i have a ****ty computer that doesnt allow me to actually see what i type. Also, look up 'modifiy' is it not another word for 'change' ? thought so, check your theasaurus

Post by **jacob360** » Sat Sep 13, 2003 7:24 pm

SWIFT_DRIFT wrote:Lol. Funny because all the S chassis started with the CA...

I stand corrected. I did think about the CA after I had made my post, but I didn't think anyone would make a big deal of it. I'm glad it amused you :rolleyes

CA or SR, the weight difference isn't as great as compared to an RB. I don't think the RB is ideal for weight balance and utilizing the 240's full handling potential.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

well hell for that matter, cram a 13B in that mofo

Post by **[Zero-S]** » Sat Sep 13, 2003 7:24 pm

Ooooo Swift I want my cookie, my car still works.

Post by **93semax** » Sat Sep 13, 2003 7:24 pm

SWIFT_DRIFT wrote:Where did the s14 and s15 get their heritage from noob. Or we could get even more technical since I was so general in my previous post. The s13 started it's life with the Ca, not until 90.5 was the SR introduced. Damn even take a look back at the s12's and earlier, no sr's there either. There would be no s14 or 15 without that. The sr is just another motor in a long line of good motors.

Noob? If you going to act ****y at least be knowlegeable of what you're talking about. The SILVIA and ORIGINAL S chassis was introduced in 1965. Everyone should know that. The S14 and S15 got their "heritage" from the CsP311 it did NOT have a CA.

:rolleyes

Noob? lol.

Post by **Onizuka** » Sat Sep 13, 2003 7:24 pm

i tell you what, all the KAs, CAs, SRs, and RBs all suck as, the FJ20ET is where its at.

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

93semax wrote:Noob? If you going to act ****y at least be knowlegeable of what you're talking about. The SILVIA and ORIGINAL S chassis was introduced in 1965. Everyone should know that. The S14 and S15 got their "heritage" from the CsP311 it did NOT have a CA.

:rolleyes

Noob? lol.

ok lets not get into a big argument here guys, its not that big of a deal, but thanks for the history lesson 93semax

Post by **nlzmo400r** » Sat Sep 13, 2003 7:24 pm

J-Spec Tuner wrote:i tell you what, all the KAs, CAs, SRs, and RBs all suck as, the FJ20ET is where its at.

were these not used in the s12s? or was it the gen before that

Post by **implict** » Sat Sep 13, 2003 7:24 pm

opinions opinions opinions........ Both good motors... your choice.

Post by **SWIFT_DRIFT** » Sat Sep 13, 2003 7:24 pm

93semax wrote:Noob? If you going to act ****y at least be knowlegeable of what you're talking about. The SILVIA and ORIGINAL S chassis was introduced in 1965. Everyone should know that. The S14 and S15 got their "heritage" from the CsP311 it did NOT have a CA.

:rolleyes

Noob? lol.

When and where did the s14 and s15 have a CA?..

Why would you even say the latter if you knew all of the above? Or was it the quick google search before this post...? And I was too general in my previous posts like I already pointed out saying "all S chassis" when I should have been more specific right off saying s13's. The sad fact is that 90% of the people on this board don't know anything beyond the s13,14, and 15's. I'm glad you do, or at least searched about it.

Post by **93semax** » Sat Sep 13, 2003 7:24 pm

SWIFT_DRIFT wrote:When and where did the s14 and s15 have a CA?..

Why would you even say the latter if you knew all of the above? Or was it the quick google search before this post...? And I was too general in my previous posts like I already pointed out saying "all S chassis" when I should have been more specific right off saying s13's. The sad fact is that 90% of the people on this board don't know anything beyond the s13,14, and 15's. I'm glad you do, or at least searched about it.

I was giving you a chance to correct yourself that's all. Back on topic:Sticking an RB in a S chassis car will dramatically affect weight distribution. Half of my RB25 is foward of the Wheel center line. Pic: http://home.earthlink.net/~4rc...5.jpgBut my car is going to be drag only, that is the way I planned it. If were to do road/autox I would go with a CA..

Post by **Onizuka** » Sat Sep 13, 2003 7:24 pm

nlzmo400r wrote: were these not used in the s12s? or was it the gen before that

yup, the cult classic FJ20ET came in turbo s12 silvia's in japan. Many people belive it is SOHC but dispite it lacking a D in the engine code, it in fact does have dual overhead cams. Its supposed to have all the stong points of the CA and SR all in one motor, but a big drawback is that it is a incredibly old motor and it woud be incredibly expensive to run in the united states because there is ZERO support for it here. Other than that, i hear it makes for a very impressive 2 liter race motor :ylsuper

Post by **krazy skwerel** » Sat Sep 13, 2003 7:24 pm

I know I would love a d30 skyline equiped with the fj20et. They look really neat as well.

RB25DET or red top sr20DET

RB25DET or red top sr20DET

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