Question for the sr20 Gurus...

['97LE]

hi! i have a 97 240sx LE and i am planning on swapping in a sr20det engine within a few months, but i am still deciding which engine to drop in... hence my question:

will a s15 transmission bolt onto the s14 sr20?

my reasoning being that i want the cheaper engine...yet i still want the 6 speed transmission.

please, only the people that know should respond

thank you

[Silvia007]

I've heard that the S15 trannys aren't that cool coz with 6 speeds, the gears had to be smaller which are prone to breaking. In japan, people do the exact opposite of what you want to do. Put a S14 transmission on S15 motor. If they don't interchange, you probably only have to change the bell housing.

[solaris22]

they are interchangable however like Silvia007 said they're very weak. My machanic has an s15 pushing low 300hp and he blew his 6 speed. if you want a 6 speed there's the HKS 6-speed for about $10,000. 6 gears are redundant anyways, that's my opinion

['97LE]

thank you guys for your replies... i'll make sure i just stick with the 5sp transmission

[quiksilvia]

i dont know about that solaris, i would love a 6th gear to go into on the freeway, but not for 10k

[lbrowne]

6 speeds are far from redundant.

cruising at 70-75 mph in my TA on the freeway, my RPMs are a nice 1500 er so rpm. never have to downshift for a hill either My gas mileage is amazing on the highway with that car considering its a v8 with a nice bit o power

Always nice to have 6th for the highway, you'll never use 6th around the city though.

edit: btw, if its proven that the 6speed breaks with the setup you are aiming for, stay clear. but I'd make sure you researched it quite a bit and tapped many resources before ruling it out.

['97LE]

that was one of my reasons for getting the 6sp. i was hoping that i could save some money on gas b/c it is sooo high now... but you also you bring up a very good point lbrowne... i think i will continue my research. when i find out for sure, i'll let you guys know... until then, thanks again and c-ya

[solaris22]

6 speeds are far from redundant.

cruising at 70-75 mph in my TA on the freeway, my RPMs are a nice 1500 er so rpm. never have to downshift for a hill either My gas mileage is amazing on the highway with that car considering its a v8 with a nice bit o power

Always nice to have 6th for the highway, you'll never use 6th around the city though.

edit: btw, if its proven that the 6speed breaks with the setup you are aiming for, stay clear. but I'd make sure you researched it quite a bit and tapped many resources before ruling it out.

Highway is the only place you'd used the 6-speed, true. Not many highways in japan so for me it's pointless. But if you drive on the highway on a regular basis, there ya go

[I H8 UR DSM]

they are interchangable however like Silvia007 said they're very weak.

Since thats very untrue, and thrown around the internet all the time....Would you please take some time out to show us some technical backing? Not, posts by people on the internet, but some sort of documentation that shows nissan produced a ' very weak' transmission for their S15's. Thank you very much.

[vwluv10338]

Just because a transmission has 6 gears doesnt mean your RPMs will be lower on the highway than a 5spd. For example look at the WRX 5spd and the STI 6spd (not the new one, version 7 for example). People can swap in a sti 6 sp but the final gear is 3.86 where the final gear on the wrx is 4.44. Therefore you have more gears but your rpms will actually be higher on the highway. Just being a 6spd doesnt mean anything, you have to look at gear ratios.

~E

[lbrowne]

Once I swap in my 4.10s instead of the stock 3.42s, I'll be able to use 6th around town quite a bit.

Like I H8 UR DSM said, I'd like to see actual offical reviews of the transmission being known to be weak....

[solaris22]

Since thats very untrue, and thrown around the internet all the time....Would you please take some time out to show us some technical backing? Not, posts by people on the internet, but some sort of documentation that shows nissan produced a ' very weak' transmission for their S15's. Thank you very much.

Well I'm going by what my machanic said. Who(like I said) owns an s15 and blew his 6-speed. He's been working on SR/RB powered cars for much longer then myself or anyone else in the states so I take what he says as fact.

[quiksilvia]

oh snap! thats an internet challenge if i've ever seen one.

[I H8 UR DSM]

Well I'm going by what my machanic said. Who(like I said) owns an s15 and blew his 6-speed. He's been working on SR/RB powered cars for much longer then myself or anyone else in the states so I take what he says as fact.

Ok, but thats hearsay, which is my point. Its not a very 'technical' leg to stand on, telling us your mechanic told u something. Like i said, its very common for people to say that, but i'd like to hear 'why'....and yes i do know a lot of the technical specific differences between the two transmissions.

[quiksilvia]

pwned

[solaris22]

Ok, but thats hearsay, which is my point. Its not a very 'technical' leg to stand on, telling us your mechanic told u something. Like i said, its very common for people to say that, but i'd like to hear 'why'....and yes i do know a lot of the technical specific differences between the two transmissions.

because the gears are weak is what he said. So a mechanic saying he knows a transmission is weak when he's owned one and has had much experience in them is full of sh.it? Believe what you want, but I'm going with the master mechanic. It may be hearsay but it's true.

[quiksilvia]

how about you guys stop and try not to turn into me and swift/buud?

[I H8 UR DSM]

because the gears are weak is what he said. So a mechanic saying he knows a transmission is weak when he's owned one and has had much experience in them is full of sh.it? Believe what you want, but I'm going with the master mechanic. It may be hearsay but it's true.

OHHH, Ok, So Nissan Must have used different materials to make their S15 diff than their other diffs...That explains it....Do you know what this magical material is?

Hey thanks "GURU" for your ever so technical discussion.

Who said he was "FULL OF ****?" cause i know i didnt....i have no doubt he told u that, or he believes that...does that mean its true? My grandmother has been here for 83 years, and she has more experience here than anyone i know...SHe will tell you ghost exist....does that mean they do? IMO, No.

Again, to clear it up....some people will tell you the S15 transmission is "weak, COMPARED to the other two, but again, if they are just saying that without any technical reason, its not a very good or valid statement", but thanks...

I havent heard too many horry stories (from japan) about S15's blowing transmission's.

And because you live in japan, and think that your mechanic has more experience w/ 'these cars' doesnt mean anything....a Transmission is a transmission, doesnt matter what car it came from or where it is made...

Im still curious, how and why NISSAN would choose to use a 'really weak' transmission in one of their cars...sigh

[I H8 UR DSM]

1 more question....what HP level will the S13 transmission support? S14? S15?

I *personally* believe a lot of the S15 transmission comments come from the fact that 'drifters' run S13 transmission's w/ their s15 motors....for obvious reasons of the 5pd vs 6sp.