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**DONOTDELETE**
07-06-2002, 09:39 AM
Later on I was wondering about putting the S15 Transmission in my S13. Im going to put an LSD on it too, but someone told me that there might be a problem with the speedometer readings, etc..has anyone actually did the tranny swap or have any information on the install? I want that close ratio 6 speed...mmm..

mattmartindrift
07-06-2002, 09:48 AM
well if your going to push a good bit of power through it, I hear the 6th gear is very weak. Also will it bolt up to KA, or SR, I guess you could make a custom bellhousing.

Matt

AEROdOUT240sx
07-06-2002, 01:06 PM
well if your going to push a good bit of power through it, I hear the 6th gear is very weak. <font size="2" face="Verdana, Arial[/img]One of the more recent issues of Super Street has an S15 silvia in it that is pushing approx. 425 hp at the wheels on the stock tranny. In the magazine is said something along the lines of "this S15 puts the rumors of a weak tranny to rest." I just though I would share that because obviously you can push plenty of power with the stock 6spd of an S15, or maybe that guy got lucky? who knows.

**DONOTDELETE**
07-06-2002, 03:31 PM
I heard of many people say that "the speed sensor is in the diff" Like ASAD said. I helped put my friends s15 engine and tranny in and it was just like mine(s13 sr) you just swap the sensors out IN the tranny. We did not get the lsd, maybe some s15's are like the older but the one that i saw may make me believe there is some misconception?

Pete

07-06-2002, 04:14 PM
Originally posted by S14SHOCKKER:
I helped put my friends s15 engine and tranny in and it was just like mine(s13 sr) you just swap the sensors out IN the tranny. We did not get the lsd, maybe some s15's are like the older but the one that i saw may make me believe there is some misconception?
<font size="2" face="Verdana, Arial[/img]Did your friend have the 6-speed transmission?

Did the tranny look exactly like yours?

Asad

[ 07-06-2002, 05:14 PM: Message edited by: asad137 ]

**DONOTDELETE**
07-06-2002, 06:22 PM
"Did your friend have the 6-speed transmission?

Did the tranny look exactly like yours?

Asad"

Yes!!! Isn't that what i just said?!
I don't know how many of you have seen the six speed tranny but i'm willing to think that it may fit in the regualar 5 speed bellhousing! Which means if it does, it also will fit a ka!

Pete

PS many people on here don't know what they are talking about. I just let you guys know what I see. That is why there must be so much confusion!

Cwestin
07-06-2002, 07:15 PM
ummm, you are INCORRECT, Sir...the 6-speed tranny has no such speed sensor, and it cannot be switched out with a ka sensor or any other sr sensor...the sensor is on the rear diff...I should know, I just finished my S15 swap w/ 6-speed tranny, and I have no Speed readings and my odometer does not function because I left the speed sensor disconnect to avoid the speed/fuel cut problems...

-Rick

07-06-2002, 07:37 PM
Originally posted by S14SHOCKKER:

Yes!!! Isn't that what i just said?!
<font size="2" face="Verdana, Arial[/img]

I was just clarifying, because the S15 six speed DOES NOT look like the S13/S14 5-speeds.

The S13/S14 trannies have a 2-piece case, the front piece has the bellhousing and the front cover, the rear piece has everyting else.

The S15 6-speed trannies have a 3-piece case, and look distinctly different than the S13/S14 trannies.

If your friend's tranny looked exactly like yours, then it wasn't an S15 6-speed.



I don't know how many of you have seen the six speed tranny but i'm willing to think that it may fit in the regualar 5 speed bellhousing!<font size="2" face="Verdana, Arial[/img]It won't, for the reason I described above. The bellhousing/case configuration is different.

Asad

[ 07-06-2002, 08:37 PM: Message edited by: asad137 ]

9591
07-06-2002, 08:46 PM
To illustrate Asad's point, here's a picture of an S15 6speed. Apologies to whoever I stole it from.

http://www.imagestation.com/picture/sraid24/pc27538259654cc87b0316574d573f908/fd91885e.jpg

[ 07-06-2002, 10:28 PM: Message edited by: 9591 ]

Society_Mike
07-06-2002, 10:03 PM
Well, its not that the S15 tranny is weak, its that after being abused, it doesn't hold up like the S14/RB20/25 tranny does (yes those are the same sans bell housing).
It's NOT common to see the 6-speed still in a S15 that has been mild to full tuned, especially with drift cars. One thing you will notice in those Japanese mags is how they swap out the 6-spd.
btw.. internally, the s15 tranny has thinner gears and I guess that is the theory as to why they don't hold up as well as the S14 unit.
The S13 tranny is the same as the R30/31 Skyline RB20's internally, considered strong, but not as good as the S14, R32, R33, C31, C33, A31, etc.. They are also very abundant and not hard to find.

[ 07-06-2002, 11:06 PM: Message edited by: VRT Elektrique ]

**DONOTDELETE**
07-06-2002, 10:11 PM
Hmm...well im tired of my floppy shifting 5-speed...I drive my friends 6-spd. Spec-V and the shifting is so much smoother and tighterIF the S15 tranny doesnt hold up well then I am for sure not going to spend all the money for the swap and it wear out. I guess I will just get a nice short shifter and the LSD later on. Does anyone have information or has anyone put the LSD on their S13? Ive heard those wear down after awhile too..

Society_Mike
07-06-2002, 10:22 PM
Well, don't decide on not doing the swap just because of reading how it doesn't hold up... you have to realize that these are cases where the SR has been tuned to anywhere from 300-900 hp and constantly driven and raced. Gotta realize that drifting here is big, and these drifters go out a few times a month and race at circuits and in the mountains under extreme conditions, so any part that has a weak characteristic to it will break and will be common.
If your driving your car with S15 tranny to and from work, and occasionaly racing a bit I would imagine you would be fine.
btw.. you can solve the "floppy" shifting problem with a short shift kit or "quick shift" like the Tomei or Nismo units.
I have a Tomei Quick Shift kit and its tigh as hell.

[ 07-06-2002, 11:24 PM: Message edited by: VRT Elektrique ]

07-06-2002, 11:09 PM
The reason you'll have speedometer issues is because the S15 tranny doesn't have a speed sensor -- the S15's speed sensor is mounted in the diff.

The tranny itself will bolt up to any SR motor. It won't bolt up to a KA, and you can't swap bellhousings from your KA tranny because the 6-speed has a different case and the bellhousings won't swap.

You will probably need a new (custom) driveshaft.

Asad

**DONOTDELETE**
07-07-2002, 08:47 AM
How much? and where can I get the Tomei Quich Shift Kit?

Cwestin
07-07-2002, 10:55 AM
Originally posted by 9591:
To illustrate Asad's point, here's a picture of an S15 6speed. Apologies to whoever I stole it from.

http://www.imagestation.com/picture/sraid24/pc27538259654cc87b0316574d573f908/fd91885e.jpg<font size="2" face="Verdana, Arial[/img]...thats mine...hehe.

-Rick

**DONOTDELETE**
07-07-2002, 04:00 PM
Originally posted by lateralusis:
Later on I was wondering about putting the S15 Transmission in my S13. Im going to put an LSD on it too, but someone told me that there might be a problem with the speedometer readings, etc..has anyone actually did the tranny swap or have any information on the install? I want that close ratio 6 speed...mmm..<font size="2" face="Verdana, Arial[/img]You have to get the s15's yoke or driveshaft. If you get the s15 yoke make sure its cut at least one foot away from the (nippleless)universal joint. If the welder melts the grease in the universal you can't regrease it! A company named Splicer makes a yoke that fits the 6 speed...but I don't have the part number.

To solve the speed sensor problem, you'll have to use the KA's speed sensor and (plastic)worm gear, then swap it over to the 6 speed. The KA's speed sensor will bolt up with no problems but you'll have to machine (bore & shorten)the KA's worm gear to these specs:
shorten to about .530" (close to 1/2")
bored (inside diameter)to about 1.11"(close to 1")

Any machine shop should be able to do this for cheap? i got mines done for free.

You'll also need to get one .190" ball bearing for the 6 speeds output shaft...its used to hold the worm gear in place and stops it form spining. Also you'll need 2 c-clips (?) the measurements are 1.030" inside diameter and .095" thick. These also hold the worm gear in place
"Double check your measures with a caliper measuring tool images/icons/confused.gif (the thing that looks like a monkey wrench), if you decide to do this."

The ka speed sensor swap won't work for a s15 using the stock computer...the sensors pulses are different!

I'll try to post some pics later on.

**DONOTDELETE**
07-07-2002, 06:59 PM
ka speed sensor swap (http://www.imagestation.com/album/?id=4291645893&congratulation_page=Y)

[ 07-07-2002, 08:11 PM: Message edited by: RiceEata ]

Spriso
07-07-2002, 08:36 PM
Don't forget that when you do the six-speed swap you don't just need the transmission (that is the easy part!) You will also need the 6-speed specific flywheel, starter, clutch, pressure plate, throw out bearing, shifter, and drive shaft as they are all different than the standard SR20DET parts.

Good luck with your project,

Michael

1970 Datsun Bluebird SSS Coupe (SR20DET/6-speed project)
1969 Datsun 2000 Roadster (SR20DE project)
1966 Datsun 1600 Roadster (killing the local V8 boys with SR20DE power)

dan240t
07-07-2002, 10:15 PM
a friend just brought up that the casing in the s15 looks very similar to the FS5R30A transmission.

thoughts?

danwagar
07-07-2002, 11:08 PM
an enjukuracing.com they h ave a b&m short shift kit. should be very high quality as it is coming from b&m. i think it's like 260? hmmm just a sec here..........

http://w1.igateway.com/clients1/tc/store/webdata_IP.cgi?cgifunction=Search&Category=nissan%20240sx&Department=short%20shifter

i'd stay away from that cheap one if i were you

as an afterthought my car has about 179000 miles with the stock shifter and though it isn't extremely tight it is very very smooth shifting and i dont ever have a problem with missing shifts or anything....maybe there is something messed up on your stock one. has anyone here ever put in washers in place of their bushings like the dsm guys do???

9591
07-07-2002, 11:13 PM
Originally posted by RiceEata:
To solve the speed sensor problem, ...<font size="2" face="Verdana, Arial[/img]Just to clarify a bit (RiceEata and I had a short PM exchange on this subject a while ago), there is an unused "port" (my word) on the S15 tranny. This is where the modified KA sensor goes. He says it works, and I tend to believe him, but it's not inconceivable that all trannies are not created equal.

**DONOTDELETE**
07-09-2002, 03:03 AM
Originally posted by RiceEata:
ka worm gear & 6spd output shaft diagram (http://www.imagestation.com/album/?id=4291645893&congratulation_page=Y)<font size="2" face="Verdana, Arial[/img]9591, yeah i forgot to mention that the 6 speed has a port for the speed sensor. But no you do not have to modify the ka's speed sensor...It's a direct fit. Also you'll have to fill the holes in the worm gear with epoxy or JB weld. Don't worry your odometer will work, mines does.... just double check the worm gears measurements!

[ 07-09-2002, 04:05 AM: Message edited by: RiceEata ]

**DONOTDELETE**
07-09-2002, 06:08 PM
Umm.. I told u guys, and as usual you dont listen! Oh well. I'm here to share and inform people, images/icons/rolleyes.gif not dismiss what you don't know!

inthewind
07-09-2002, 06:19 PM
Post deleted by inthewind

**DONOTDELETE**
07-09-2002, 08:29 PM
Originally posted by demcj:
</font><blockquote><font size="1" face="Verdana, Arial[/img]quote:</font><hr /><font size="2" face="Verdana, Arial[/img]Originally posted by RiceEata:
ka speed sensor swap (http://www.imagestation.com/album/?id=4291645893&congratulation_page=Y)<font size="2" face="Verdana, Arial[/img]what the?!

you've got to be kidding.

and this chicken scratch drawing is supposed to prove something?

let's see some photographs.</font><hr /></blockquote><font size="2" face="Verdana, Arial[/img]Huh images/icons/confused.gif
Would a photograph of a modified worm gear on the 6 speeds output shaft prove anything? no!
I wasn't sure if the worm gear and the speed sensors gear would even come close to touching, so i never even thought of taking pics, sorry dude.
I did ask a friend (Brad P./ s15e6kdet) to take pics when he did his, but i don't know if he did. If Brad never told me that the KA's speed sensor was a direct fit into the 6spd tranny. I would have never even thought of doing it.

At least i keep that drawning i made 4 months ago. Now guys with 6speeds can understand what it takes to get there odometers working.

[ 07-10-2002, 01:03 AM: Message edited by: RiceEata ]

9591
07-09-2002, 10:50 PM
Originally posted by demcj:
and this chicken scratch drawing is supposed to prove something?<font size="2" face="Verdana, Arial[/img]I don't think he was trying to prove anything, but just illustrate the written instructions he provided. It definately cleared things up for me.
Some of the important points that I've gleaned from the words + pic are (and correct me if I'm wrong, RiceEata):
1) Nissan designed the 6speed with provisions to install a speed sensor, but apparently decided to locate it elsewhere; so
2) The 6speed does not come with the worm gear needed to drive a speed sensor, and the hole for the sensor is plugged; however
3) The plastic KA worm gear can be modified to fit on the shaft, and a few other easy-to-find parts (ball bearing, snap-rings) can be installed to hold it in place; and
4) The KA sensor can then be installed into the tranny, and will function.


Originally posted by S14SHOCKKER:
I helped put my friends s15 engine and tranny in and it was just like mine(s13 sr) you just swap the sensors out IN the tranny.<font size="2" face="Verdana, Arial[/img]
Umm.. I told u guys, and as usual you dont listen!<font size="2" face="Verdana, Arial[/img]See, now what you told us was that you just swap the sensors. First, there's no sensor to swap out of the 6sp, so you just install the KA sensor. Second, you didn't mention anything about having to remove the KA worm gear from the KA tranny, modify it, and then install it in the 6sp along with some other parts. That is *not* "you just swap the sensors".


Originally posted by RiceEata:
The ka speed sensor swap won't work for a s15 using the stock computer...the sensors pulses are different!<font size="2" face="Verdana, Arial[/img]I'm not quite clear on this; are you saying it won't work with the KA ECU, or the S15 ECU?

[ 07-10-2002, 12:00 AM: Message edited by: 9591 ]

'97 S14 SE Turbo
07-09-2002, 11:25 PM
the modification is for S13 and S14 SR owners to run the S15 tranny...

Nismo offers a mounting kit to allow the S13/S14 SRs to use the S15 tranny. They also sell the driveshaft required to do it.

9591
07-09-2002, 11:37 PM
Originally posted by White Bunny (hehe..."White Bunny"...):
the modification is for S13 and S14 SR owners to run the S15 tranny...<font size="2" face="Verdana, Arial[/img]OK, I got it; it works with all SR ECUs, and *not* the KA ECU.

'97 S14 SE Turbo
07-09-2002, 11:44 PM
and not the S15 SR ECU...

So, a S15 SR can be controlled by a S14 ECU, and using the modification, retain the 6 speed tranny...

9591
07-09-2002, 11:58 PM
Alrighty; so someone who gets the whole S15 package, except for the differential, cannot use this mod? I'm just trying to get things fully cleared up.

**DONOTDELETE**
07-10-2002, 12:31 AM
s13/s14 sr's and both ka speed sensors are the same.
The KA/sr speed sensor will work with the KA ecu's,S13/s14 sr20de/det ecu but not the s15 ecu. The s15 ecu uses the s15 speed sensor thats mounted in the diff to get a speed reading. And the sensor in the s15's diff has a different pulse, than the KA/sr speed sensors.

Just a thought...If you have a s15 sr20det package with everything excpet the s15 diff, and did the ka speed sensor swap. there might be a way to use the KA's ecu to drive only the speed sensor.

[ 07-10-2002, 01:34 AM: Message edited by: RiceEata ]

9591
07-10-2002, 12:59 AM
Originally posted by RiceEata:
s13/s14 sr's and both ka speed sensors are the same.
The KA/sr speed sensor will work with the KA ecu's,S13/s14 sr20de/det ecu but not the s15 ecu. The s15 ecu uses the s15 speed sensor thats mounted in the diff to get a speed reading. And the sensor in the s15's diff has a different pulse, than the KA/sr speed sensors. <font size="2" face="Verdana, Arial[/img]Jeez, White Bunny #18 seemed to be implying that your mod would not work with the KA ECU (the implication only coming from the way his post was phrased in relation to mine). You are stating that it flat out will work with KA ECUs and S13 & S14 SR ECUs, but not with S15 ECUs. Correct?

edit: Nevermind. I was so into figuring out what sensor would work with what ECU, that I forgot that there's no way an S15 6sp tranny would work with a KA motor, short of some very expensive custom work.


Just a thought...If you have a s15 sr20det package with everything except the s15 diff, and did the ka speed sensor swap. there might be a way to use the KA's ecu to drive only the speed sensor.<font size="2" face="Verdana, Arial[/img]I'm starting to hate you images/icons/wink.gif Seriously, though, I agree it might be possible to do that, and it would almost certainly be possible to design an electronic interface to install between the sensor and the S15 ECU.

[ 07-10-2002, 02:38 AM: Message edited by: 9591 ]

'97 S14 SE Turbo
07-10-2002, 10:45 AM
no, no, the KA speed sensor is needed, it's more chassis specific, than engine specific. Many SR swaps uses the KA speed sensor since it's calibrated to the speedometer, and the rolling gear (wheel diameter, etc, etc).

By going this route of mounting the KA speed sensor vs a SR speed sensor, you don't have to go and buy a SR speed sensor...

The smart folks that really want a S15 motor would be buying the motor, tranny, and half the driveshaft. Ditch the S15 ECU control system, and use the S14 ECU control system, but controlled with a S14 SR Power FC to run the larger 480cc injectors, and use the KA tranny speed sensor so that everything would work. Heck, even the rear diff can be installed and still work, so you get the HLSD...

Or the cheaper route is to go for a S14 SR swap, then buy the S15 tranny, driveshaft, and rear differential... Voila, instant S14 with 6 speed tranny without the S15 SR speedo headach... or some of the cost...

I've dreamt of building a Fastback with S14 SR running gear with S15 transmission and S15 HLSD with flared fenders plus a big vented hood... and to get the tranny to work either RiceEata's method or the Nismo tranny mounting package...

**DONOTDELETE**
07-11-2002, 12:21 AM
Originally posted by White Bunny:

The smart folks that really want a S15 motor would be buying the motor, tranny, and half the driveshaft. Ditch the S15 ECU control system, and use the S14 ECU control system, but controlled with a S14 SR Power FC to run the larger 480cc injectors, and use the KA tranny speed sensor so that everything would work. Heck, even the rear diff can be installed and still work, so you get the HLSD...
<font size="2" face="Verdana, Arial[/img]You'll also have to get a set of s14 coil packs and an igniter chip. The s15 packs are different, each coil pack has its own igniter chip.

Another choice for engine management expectically if you don't get the s15 harness, would be to get a Haltech (E6K). Go to www.hitman.hm (http://www.hitman.hm) and email them. They (Matt) has maps for the sr20's... it'll get you running. Even though Matts maps are pretty much set, make sure you do your research before you order a e6k kit. You'll need a laptop with 95-98 windows for tuning. Anything above 98/win second edition won't work with the haltech programs, win/2000/ME, etc.... Cause the MS-DOS(operating systems) in computers changed after 98/win. For more info on the Haltech and P'fc ecu's go to www.rx7club.com (http://www.rx7club.com) forums, they have a standalone engine management forum. One of the sponsors for that site sells the cheapest Haltech kits, with just about everything you need, for alittle bit over a grand.

This was kind of off subject but though it would be good for you guys to know. images/icons/wink.gif

[ 07-11-2002, 01:31 AM: Message edited by: RiceEata ]

SR240
07-11-2002, 08:01 AM
no, no, the KA speed sensor is needed, it's more chassis specific, than engine specific. Many SR swaps uses the KA speed sensor since it's calibrated to the speedometer, and the rolling gear (wheel diameter, etc, etc).

By going this route of mounting the KA speed sensor vs a SR speed sensor, you don't have to go and buy a SR speed sensor...

The smart folks that really want a S15 motor would be buying the motor, tranny, and half the driveshaft. Ditch the S15 ECU control system, and use the S14 ECU control system, but controlled with a S14 SR Power FC to run the larger 480cc injectors, and use the KA tranny speed sensor so that everything would work. Heck, even the rear diff can be installed and still work, so you get the HLSD...
<font size="2" face="Verdana, Arial[/img]White Bunny, I'm considering doing what you suggested with the Power FC for the 14 ecu. My current setup is that I have a full 15 setup. If this is true changing the gear worm won't work for me bec I'm running the 15 ECU right? Would the Power FC for an S14 SR correct this problem? Would that then allow me to use the KA speed sensor method? I've been without a speed sensor for 7 months now and it's really time to get that working again whether it be with a 14 tranny or now.

TIA

Bryan