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Ka24E (SOHC) to Ka24DE (DOHC) F.A.Q.~

42K views 32 replies 21 participants last post by  FormulaDz92  
#1 ·
I asked alot of questions, and so have others with no reall answers to how to do all this, I finally finished it, and Am gonna help out some others.

So here goes~~~

So you start with a 89-90 sohc 240

ANd you wanna install a more ready available doch motor,

What you need to do this::

any ka24de motor and tranny. The sohc tranny will work if you have dohc bell housing.
s13 dohc ecu
s13 dohc wiring harness,
s13 dohc distrib, and coil
s13 dohc tach
s13 dohc throttle cable
s13 dohc maf sensor.
s13 dohc exhaust manifold, and factory downpipe.
s13 dohc intake. manifold, must be used if using a 94+block
s13 dohc air intake
s13 dohc powersteering lines (if you want it)
s13 dohc cruise controll (if you want it)


Preping the car. First off remove old sohc motor,and Tranny, you can do this at the same time, as i did, just make sure you go inside and take off the plastic pieces and remove the shifter. And unbolt the driveshaft. Also remove all the other pieces such as powersteering.And remove the stock computer and wiring harness, This is by far the hardest part of the swap, because the wiring has this plastic L shaped thing taped to it under the dash, and you can NOT pull it thru the firewall, (i tried) so you have to reach up under there and cut it away,, Its really a pain in the ass. You also wanna go ahead and install the s13 dohc wiring harness at this time so you have more room under there to try to wiggle wires thru the hole. Dont plug the wires into the ecu yet because you have some wiring to do under the dash. Next Degrease everything, Grease suspension... what ever you wanna do.

Next prepping the dohc motor to install. You need to remove all the old sensors from the sohc tranny, and some other ones on the motor, to replace the dohc one if using post 93 motor and tranny. If your using pre 93 dohc motor, then all your sensors will work. If using a post 93 block you need to now install the s13 dohc intake manifolds. I used the 96 upper intake and 93 lower intake when i did my swap, just so i coulld remove the secondary butterfly set, that seemed to trap up some airflow. I also capped all the vacume lines at this time and blocked off the egr valve. ((only if you live in a good county)).

Ok now that you have the wiring harness in the car drape it over the fender out of the way, And install your motor. I took off the front bumper and headlights and hood when doing my install so i would have more ability to get under the hood of the car (the pignose sticks out FAR) The motor goes in pretty easy, I did it with the tranny still atached for simplicity of it all, and so i didnt have to lay under the car and attempt to install it by my self! Also make sure the shifter is out of the tranny, or your gonna tear it up!.

Once the motor is in, Its all cake. INstall the driveshaft, it just slips right in,and then bolt the thing together, Next Just plug up the harness to where each thing goes, its realy easy, no rewiring anything under the engine bay. if the distrib is still in and hasnt been knocked around then your car even may still be timed. HEHE. Your radiator hoses require a bit of tweaking, but they do work.

Next install your throttle cable, its simple, just two bolts under the dash, and its in and out. I think that the sohc would work, but it would be pulled tight across the top of the motor and would look pretty bad, with the s13 dohc one you can tuck it back out of the way, and it looks alot better.

Since your inside the car, install the shifter Its simple! make sure you top the tranny off with fluid. and walla.

The next and easiet thing of all to do is connect the wires under the dash, there are 6 wires that you will need to attach, and thats it, the rest go to a check connector, and are not required to get the car running::

Yellow/red --Tach
Yellow/Green--speedo
orange--ignition start
black---ground
blue/black---water temp sensor.

These are the same color wires on each harness, the only reason that you have to remove the connector, and cant use it is because the wires would not meet up in the same place, but its really easier than it may look.

Also you will need to remove the cluster from the dash and install the Tach, its only held in the back of the cluster by three screws. Its easy also.

Last is to bolt all the body parts on and fire it up, you should be ready to go, if it doesnt start then check for spark and then for fuel. This happend to me and i finally found out why, I didnt install a ground on the back of the motor, no big deal but it was kinda pissing me off.

If you have any questions just post them and ill answer asap. Or pm me. But Just remember guys Its always easier than it looks.

have fun!!

~Chris
chrisreedtn@hotmail.com
 
#2 ·
So your saying the s13 tranny wont bolt up to any of the s14 dohc engines without the s14 bell housing? what about those 5 wires, connect them were? what about the rest of the wires like injectors, maf, tps, etc? do the rest of them match up?

thanks again man, this is really helpful

jon
 
#3 ·
The sohc tranny will not unless you use the dohc bell housing.

there is 6 wires under the dash, the colors match up, its simple. Just cut the wires from the stock sohc harness that go to the white connector under the dash, you'll see it when you remove the ecu cover, its about 6 inches above the ecu, But just cut them right about the ecu, then when you have the dohc harness in there, cut off the white connector at the end and sauder the ""Matching colors"" listed above together, and your done, Its not that complicated,

But yess, if your using a 93 wiring harness, which you will have to do, because the 94+ has internal coils and the pre93 has an external coil, but anyways, The 93 wiring harness will plug in to the injectors, I had used the fuel rail off the 93 which you may need to use, im not sure if the later injectors are a different impedence, i dont think so, and i think that they will work, but for now lets just say that everything will connect, if connecting it to 93 parts.

-Chris
 
#16 ·
ok, sorry for the unholy thread bump from 4 years ago, but i thought the ka24e and ka24de bellhousings were the same?? i'm concerned about this cause i bought a sohc hatch for the 5 speed conversion, and i wanna know if i'll need to get another bellhousing before i get started on the swap soon.

i've heard on here before that the e and de bellhousings are interchangeable, so which is it?:12dunno

also, is this guy just referring to s14 de's?
 
#4 ·
im guessing this is gonna be much harder if i use a 95+ engine, wiring harness, ecu. im gonna have to change alot more stuff arnt i?
 
#5 ·
um your gonna have a shit of a time trying to get that to work. You really need the s13 stuff for simplicity sake. I used a 96 engine in mine. with 93 stuff.

-chris
 
#6 ·
stupid obd ii
well thanks for your help
you answered all my questions.

-jon
 
#7 ·
Q: Does the 95 ka24de have an internal coil?
A: Yes. S14's (95-98) all have the internal coil. When swapping an S14 KA into an S13, you'll need to use the S13's distributor


as per unstable-hybrids.com


-Chris
 
#8 ·
hey, I'm getting a motor from a 97 240. It comes with everything except the ecu which i can pick up from a local junk yard. Uncut harness,motor, tranny;basically everything except what i said. Your telling me that i need 93 parts? If so, what parts should I use?
 
#10 ·
yes you need 91-93 dohc parts. You dont need the tranny, just the sensors, any dohc tranny will work, and used the same drive shaft. I have been told that the sohc tranny will work but you need the dohc bell housing to make it work.

-Chris
 
#13 ·
Just double checking here, you only need the 91-93 engine harness right? Not chassis or anything else? (i.e. the point behind having to splice) :smacked49
 
#15 ·
by engine harnes, what do you mean... just what hooks up to the engine right? now what do i do with the rest of the wires? like the fuse box and the wiring for the alternator and lights and everything else. does the stock stuff stay in there?
 
#19 ·
[Elvis Voice] Thank you... Thank you very much [/Elvis Voice]
 
#22 ·
don't quote me on this, but i believe that the only thing different between SR and KA transmissions is the bellhousing, and i think it's the same way with the CA.

also, i think the CA trans has a different 5th gear. shorter ratio, i presume. you should search for this. i know i've seen a thread on this exact subject before.
 
#24 ·
this is great info so if i have a s13 with sohc motor and tranny but i want to keep the tranny and put a s13 dohc i just need ecm and wire harness but the motor includes everything like distrubitur and all sensor will it work.just click and play??
 
#26 ·
hey im new here i have a 90 hardbody with a 97 ka24de motor how can i tell what harness i have? i dont know if i have a s13 or 14 harness, cause i need a distributor for it and i dont know which one to get. and would i need to get a 14 chassis harness for the truck or could i use my stock hardbody harness could i use the hardbody gauges? need help bad
 
#28 ·
Tough 5-speed swap

Ok here goes. I bought a s13 automatic ka24e sohc. In the process of doing a 5-speed swap. The parts im using are off a 5-speed ka24de dohc that I had and a tree fell on. ive got everything put in but the tranny. I got it up in there but the bolts don't seem quite long enough. I just want a confirmation that my tranny wont work and that I need to either get a sohc bell housing or just a new sohc tranny. Or If I go buy longer bolts, will there be any issues with clutch clearance and so on. PLEASE any help will be appreciated. Thank you!
 
#29 ·
I bought an 89 240sx with a KA24-DE in it. It runs great except the MPH Gauge doesn't work. I have the tranny out right now to change the clutch and I'm probably going to get a new trans all-together because the input shaft bearing is messed up on this one. Anyway I just want to make sure I get the right tranny and that when I install it the MPH will work. Thanks