Sr20det

Out of the black tops which have more power the s13,s14 or s15 I'm sure the s15 has the most out of the three but what about the s13 and s14 which has the most? Also I wanted to know can you use a 5spd trans for the s15 sr? Thanks for the help

S14 and S15 are the most powerful of the stock RWD SRs, as both have NVCS (variable cam timing), the S15 has more than the S14 because of the turbo differences and larger injectors. But the both are better than the S13 SR.

The 5spd trans will bolt to the S15 no problem, but it uses a larger flywheel and clutch, so you need to either clearance the bell housing or use an S13/S14 flywheel/clutch.

seishukuS14 and S15 are the most powerful of the stock RWD SRs, as both have NVCS (variable cam timing), the S15 has more than the S14 because of the turbo differences and larger injectors. But the both are better than the S13 SR.

The 5spd trans will bolt to the S15 no problem, but it uses a larger flywheel and clutch, so you need to either clearance the bell housing or use an S13/S14 flywheel/clutch.

Correct, it'll all swap over. The difference is 10MM IIRC, S15 has a 250MM clutch and the S13/S14 has a 240MM.
Minimal really, and wouldn't make a difference if you were to run an uprated clutch set anyway.

swapping the trannys out is a good idea since i hear the 6 speed is actually weaker than the 5speed

Oh yea. Plus the common versions of the 6 don't have a port for the speed sensor, since the S15 has it's speed sensor in the rear diff.

Swapping the S15 SR20DET isn't possible at this time, because the S15 engine is highly dependent on the entire chassis harness, and will throw codes and probably run incorrectly.

thanks guys for all the info it's been a great help

there are plenty of people who have swapped s15 sr's arro. they are pricy though.

to use the 5 speed on the s15 you need to use the 5spd clutch and flywheel setup. im 99% sure the input shaft is different on the 6 spd and wont work with the 5 spd clutch disc and vice versa.

the s14/15 motors are more powerful stock, and respond to mods well.

but, if you are looking to build big power, just stick with an s13 version.

the s13 black top is essentialy a redtop, but has a few little updates.

I said "at this time", because nobody has done the research to figure out the wiring. It's nothing like swapping in an S14 engine. Far more complicated. Yes, it's been done, but on cars with a lot more background research. None of that legwork is done for the S12.

Looking briefly at the wiring diagram for an S15, it doesn't look any different than a S13/S14 KA or SR... I could be wrong though.

you're not.

Sterling and I were discussing this, I don't think it's the wiring per se, but the electronics itself.

In the 2G Neon community we have this same problem... my Neon is a 2000 year car, but 2001 and up are OBD II "NGC", or "next generation computer", and the ECU is very dependent on the rest of the componentry within the car. It's why you can't just swap an engine and ECU for the SRT-4 motor, you  need to do a total chassis harness conversion. Even between the non-SRT Neons... the 2000 and the 2001 have virtually the same wiring structure, but the NGC is far more dependent on its entire sensor array. That's why I want to turbocharge my Neon, because the 2000 is not an NGG and will be easier to tinker with.

My understanding is that the S15 is OBD II NGC, and has that same dependency on the chassis components. My reasoning is that you would have to integrate the entire chassis harness into an S12 and make everything work, or it would throw CEL's at the very least. At least the S13 and S14 motors only require the engine harness and ECU, and a few wire modifications.

I could be wrong, but considering that the S15 is supposed to be pretty advanced compared to the previous incarnations...?

Japan's emission systems aren't as tied in as ours, so it's not going to go nuts. At least not on the years the S15 engine was made anyway.
They don't have OBD1 or OBD2, they actually just have the CONSULT/CONSULT II diagnostics, but nothing nazi like we get here.

It's got EGR and EVAP solenoids, but the JDM ECCS doesn't usually care if one goes AWOL or not.

i dont see anyone putting a s15 sr in an s12 anytime soon anyway.

brewster240i dont see anyone putting a s15 sr in an s12 anytime soon anyway.

I got an S14 SR in mine, close enough!

With the money you would save buying a s13redtop or blacktop you could put in it and probably make more power than a s15 sr

Depends on how you look at it... If you know how to use the VCT properly, you can make boat loads of torque over the S13.

S13 SR's are becoming more and more dyno queens.

dyno queen

http://www.youtube.com/watch?v=jBsr2huw8gY

you need to experience this car in person. 9000 rpm's of amazingnous.

Also an S14 engine... Though sadly not using VCT.

thats an s13 engine.

with a hybrid valve cover on it.

brewster240i dont see anyone putting a s15 sr in an s12 anytime soon anyway.

in my opinion, no, its not.

s14 sr is nice for a powerful street car, and will bolt in with mixing parts.

s15 if you want to use the 6 spd you will have no speed o meter, need custom driveshaft, etc and its know for being weak.

so you think the s14 blacktop will be fine then?

more then fine.

especially after being used to a 18et

brewster240thats an s13 engine.

with a hybrid valve cover on it.

brewster240more then fine.

especially after being used to a ca20e

sideways_s12fixed lol I'm putting it in my blue car because ut's not worth my time to fix the ca20

jeffwins24Make a CA20ET and get a big turbo and boost 18psi and blow it up    

seishukuThe extra kickout cover on the head says otherwise...

I must have been looking at different pictures then...

arent the s13's rated at 205hp and s14 rated at 220hp and finally the s15 at 250hp

yes u should be correct

EightySix200SXarent the s13's rated at 205hp and s14 rated at 220hp and finally the s15 at 250hp

silverarrow27Yes.

Valve cover Brewster posted is correct, that's an s13, s14/s15 engines have the notch in front of the motor for the vtc.

SR20DET of the S15 is 250hp because it works with a GT28R.

SR20DET of the S14 is the best

why's the s14 better than the s15 even tho the s15 has more power?

Cheaper.
Easier to find.
Cheaper.
Don't have to deal with the weak ass 6 speed trans.

...

Cheaper?

Seriously, the S15 motor usually runs for 3 grand, where the S14 can be had for $1200? Maybe a little more, depends on how must the seller wants to rape you.

yeah around here in the northeast, a decent s14 full swap will be around 2500, s15 usually start at 3500 if they include the trans, but usually dont come with the diff, driveshaft, etc other crap needed.

seishukuActually it's an S13 front valve cover welded to an S14 valve cover, hybrid. I've seen that done before.

See, when I went to MA-Motorsports.com, and viewed pics of Brian's S13, all the pics are S14/S15 engines. Check it for your self.

i wish rps1392 would post more often. this guys a genius when i come to anything Nissan but hes very busy. he has a lot of good info. he's helped me out a lot.hes a great guy.

Could I just say that if your already anticipating that ur gonna modify it anyways, all SRs would work. The question you asked was which SR would have the most power and that is, stock wise, would be s15. If your worried about the 6 speed tranny, then get z32 tranny and mount that in there. I'm getting one for the hell of it if I find one. It all depends on your budget REALLY. Take it from me. Do your research. All of this lecture I got from someone here in 2004. And I'm still learning more about the SR as well like... fittings. This is where I'm at now.

Just to add my two bits in. I own a 98 240sx with a s14 sr20det. before purchasing my motor i completed the same research your doing now. and the facts are the s15 and s14 motor are almost exactly the same after modification. turbo, injectors, manifold etc, the six speed transmission in the s15 is extremely week. picture room for five gears and cramming six........... i wonder.  

But if your going for cheap power. buy a s13 motor pref red top, swap injectors turbo and exhaust. re torque your head bolts and boost it up.  i know personally a person who is running 28psi on stock s13 internals with a rom tune and apexi afc. been daily driven and raced for the last 18 months.

(s15 sr = waste of money)

thank you guys for the info....

s15 sr is not necessarily a waste of money imo. Picture this...s14 sr, then add a good diff..You're approaching the cost of s15sr swap. If you pick your swap, chances are you'll be able to find the s15 hlsd with it. I did and am very happy with it. In stock form, the s15 makes more torque, lower in the powerband, drives smoother, and has, generally, a more agressive fuel map even compared to the s14sr. That's probably due to the larger injectors.

The wiring was a complete cluster f**k. One of the biggest problems i found is that the motor, and as result, related harnesses, is that it has never been in a lhd car. Just more complications. Also, I'm anal to the point I needed to keep all the accessories. ABS, Cruise, wipers, and a/c all work. Oh, and nobody's done pinout charts of the f4 connector for the s15, yet. so I had to split the harness and trace everything with both fsm's.

Lastly, if you're going ka- to sr-, swap bellhousings. They go right together, and the ka- trans is slightly stronger than the sr 5-spd. Don't forget, trans gear ratios are different, so swap final drive gears.

if he has a ca20e car, the hlsd wont fit, so that is out.

secondly, the transmissions arent any stronger from ka, and the only gear that is different is 5th, and its not a noticeable

unless you had an early s13 silvia, the rears are the same, ca18 s13 had 4.30

Sorry, I meant the gear ratios between the s15 6-spd and the ka- or s13 or 14 5spd

do you have any proof that the s15 6 speed is weaker. I have heard alot of talk about it but never any proof of it actually being weaker