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Abdul's k24 or k20 Swap build/Guide with Complete Wiring diagrams

193235 Views 136 Replies 23 Participants Last post by  Nivek
Hello there, this is about swapping a k24 or k20 in a Crz. In this swap a k24a2/a3 is being swapped. Purpose to do a K24 swap is that it is a lot cheaper than k20 and has more torque and is at 200 Hp and has very much potential to go up in Hp range very easily, plus is boost friendly as it has 10.5:1 CR.
Until recently ( Nov 18,2017) HAsport only made mounts of K-swap(k20 only) for either Civic Si(k20z3) transmissions or DC5 ones which added to swap cost as they are very expensive. If you were to use a k24 block, you would still need a k20z3 or a K20 DC5/RSX-S transmissions. But now HAsport makes mounts for CRZ which support k24 transmissions (TSX 6 spd, Civic si 2012-2015).So now a complete k24 swap can be done in very less $$$$
Now presenting the video series which contains many new things,covers both k24 & k20 route.Also covers Zf1 & Zf2 aswell as Fit GE(2nd Gen) and Fit GK(3rd Gen).

Complete k swap guide part1
Estimated Project cost will be 4500-5000$.(Can go up depending upon labor of shop). This will be very feasible alternative to SC or Turbo kits available for Crz which cost from 3000-5000$
k24a2/a3 with 6 spd manual transmission 1500$-2000$
Shifter & cables= 150$|Model:Civic&hash=item41d02b4fe4:g:GeEAAOSwYyxZf5NL
HAsport Mounts for k24 (now they make them) 700$ (You have to mention k24 and its transmission type when placing order)
Flashpro/Ktuner: 700$/450$
Axles: 500$(HAsport crz for k24, tell them to ship the k24 ones as the k24 half shaft is longer than k20 )
Or you can buy Insane shaft axles which are rated for 500 hp ,I contacted them and they got data of axles from Hasport (Thanks Brian for sharing data for our sake).So now you can get those in 350$ instead of HAsport 500$ and more strong also than HAsport.
It has come into my information that stock k20z half shaft and axles are bolt ons. This engine comes in Civic Fd1(Malaysia) or you can search which alternate version internationally.
I have tried Insaneshaft axles in my Fit and both axles did't fit. So kindly contact Insaneshafts before buying that if axles dont fit they will return them back and refund you.

K20 idler pulley optional: 40$(If k24 have hydraulic Power Steering pump pulley and you don’t want to use that, just disconnected the hydraulic PS lines but keep the pump and pulley there for belt sake, will save you Idler pulley as well as new serpentine belt cost)).but will require a slight modification in power steering pump so that it doesn’t get jammed running without any oil in it.
Civic Si wiring: 120$
Si ECU+ Ignition key Optional =190$( not needed if you can tow your car to Honda dealership and match the new ECU with your old CRZ keys
Custom 2-2.5” exhaust=??
Headers OEM k24
Civic Si primary O2 sensor(Or you can use CRZ one,Yes it was done in a swap in Zf2 chassis in Malaysia and it worked) =120$
Secondary o2 sensor=Optional.
Radiator OEM (its more than enough, we have three k20,s and two 24 running with OEM crz radiators and are just fine, temperature remains 90-94 C.
Misc=IAT sensor, wiring grips (If you don’t want to use your Crz one’s)=50$,coolant 4L,oil etc
Spark plugs can use the ones that come with engine(k24 or k20,BKR7EIX) but I advise new: 35$
Tune: you can use any base TSX/Si map given in Flashpro calibrations
Honda dealership matching of your new immobilizer key and civic Si ecu=50$ ?
Intake: Can use that comes with new engine or just a short ram with K&N filter =50$
Swap shop labor if you don’t have engine stand=? 400-500$ ??(shops here cost 120$ for whole engine swap)
The purpose of this thread is to do almost all work as D.I.Y and at end if you don’t have engine stand to put the engine in/out than you can go to a shop to put engine in just in few hours.
As labor is not so cheap in some countries and they cost per hour bases, so purpose of this build is to get most work done before going to workshop for final engine swap.

Some of you may know me for my Honda Fit Hybrid k20 swap.
Here it is.
It had same LEA Mf6 engine of a CRZ and the wiring of it was copied from a k20 swap crz but was never documented in detail. To date the wiring of CRZ k20 is difficult but it is about to become real easy.
In Pakistan first k20 Crz wiring was done by electrician M.Anwar in 2013. It took him near 2 months to do so as at that time very little support was there about the swaps in modern OBDII cars, yet a hybrid. The fist CRZ was done using two ecu method. The OEM k20a ecu using kpro and a crz ecu.
2nd crz was done by using single ecu of Civic Si USA(2007-11). This method is superior as it has functional OBDII port and the gauge cluster, ABS etc works. Still no documentation was done.
3rd was my car.
here is the thread about its swap
Although I wanted to document the wiring in detail in that build but I failed to do so because it was really complex and i was a beginner in this field.
At that time I promised to myself that I will document it so that its easy enough to do as D.I.Y and the one doing swap is prepared for what is required and what problems he will/might face, like AC compressor hitting chassis and break booster hitting the engine, Radiator fans hitting the intake manifold etc. If you have an automatic CRZ than don’t worry either because I will document all the method from CVT to a manual conversion and it very easy because even in a manual crz you will have to use the new shifter of civic si/tsx and cables. so only thing remains for a cvt is to add a used clutch paddle from a Honda CRZ/Fit/jazz/City/Civic along with its respective cylinder. Conversion will not cost more than 200-300$.
So with no further delay lets start
In the name of Allah, the Most Gracious, the Most Merciful

English is not my language so I apologize for any spelling and grammar mistakes.

Special thanks to Mr.Anwar and Ustad Danish who helped me when I needed.
Here is crz I bought recently for the project. Its a 2010 MT.

Here is the k24 engine for swap

This thread will mainly focus on doing all the work prior to engine installation into engine bay. Goal is to swap k20/24 in just few hours.
There are some sensor grips and main wiring grip you need to buy. Its better if you have a junk yard nearby. If you want to use a k24, than you will have to change oil pressure sending unit, Knock sensor grip, Crank sensor grip.(All these can be used of your Crz engine, but if you plan to return your crz to stock in future and don’t want to use any of its parts than you will have to find these from a junkyard or ebay etc). You will need IAT sensor and its grip.(The crz uses MAF sensor which has IAT sensor integrated into it ,so you will have to buy it, I will give its details in sensor wiring section)
As JDM models don’t have Hill assist so at this time we don’t know if it poses any problem in a k20 swap crz which has it.
I will cover each section of build separately but emphasizing most on how to do wiring on your own.

Here are the link to quick navigate to the pages..
Sensors sweap and sensors wiring connectors modification and engine preperation depending upon engine Page 1
The new forum format has changed the page numbering so much.

Break booster,oil pump,HAsport mounts and instructions Page 2
Engine preperation,clutch,flywheel installation etc etc Page 3
Alternator and starter wiring,immoblizer,pinouts etc Page 4
Main wiring,vss wiring,O2 sensor wiring etc etc Page 5
Axles, halfshaft,Shifters and calble, engine swap and fuel lines and their adapter sizes, some wiring Page 6
Exhaust and gearbox modification Page7
Turbo k24 Sidewinder CRZ build Page 7 & 8
Page 9:
Turbo feed,retun,oil pan modification,fuel pump,fuel injecotrs(FIC 1000cc)
Page 10 The Return Fuel setup,FPR and Fuel Lines

I also have updated Dropbox folder regarding all the offline save of this build upto page 7 of this build.I advise download and save a copy of that becasue some time pictures get deleted from hosting sites.
Dropbox folder
Diagrams and pics
Select option 'Download" on top right corner and it will download as a Zip file.extract and open.its 128 mb download uptill now.
For motivation i have made a collection of videos.Enjoy ;)
Now presenting the Complete K-Swap guide in video series.
All the routes,k24 or k20 in a Honda CR-Z Zf1 chassis aswell as Zf2
Honda Fit Hybrid,Honda Fit GE,Fit GK or in modern Honda.
Save the money and labour.Learn to do it with yourself.
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Gear box cover and exhaust

As i told earlier that its best to use CRZ shifter mechanism coupled with accord v6 manual tranny shifter cables.thats easiest and best route. but as i used type R shifter so i had to modify(a lot) gearbox plastic cover too. Leason learnt the hard way ;)

After many trial and errors.removing the hitting parts

Important Note:
For k series 6 speed lSD trannies like k20z3 or DC5(y2m3) or NPR3 this type of shifter is needed where the main cable is attached to top of gear lever. i .e. by moving shifter in forward direction the shifter cable also goes forward.

But for non lSD or 5 speed transmission(W2M5 or RPD-6)or base rsx, what i found is that the shifter required must have the link cable under the that when the shifter is moved forward the cable turns backward.i.e it moves 180 degree opposite. You can understand with the pics.

So this is important when you are ordering/buying your transmission,buy the shifter and its respective cables accordingly.Now you can recognize from pics on ebay what will you require on your tranmission.

No matter what i tried the cup holders kept hitting the shifter cables.

Atlast i cut them off with sharp knife0:)

To fill up the space i used a cardboard piece

Pinted it up.One peice is needed. I cut another one just in case..

The end result


I already have discussed much about header.Lets quickly cover rest of exhaust and the touching areas where you should look.
The main area is sway bar. Universal K-headers do not have the clearance for it in CRZ.
I have a custom made bad heaer which hits the sway bar. Here the exhaust shops are horrible.The dont have facility to bend pipes beyond 2 inches.

Note:If you mount engine to lower hole of HAsport mounts,the chances of headers hitting sway bar above picture the header had good clearnace when engine was on upper hole of mounts.after i did my oil pump/pan mode i mounted engine to lower position and the header start hitting sway bar.(not fault of exhaust shop as they made the size when engine was on top position).

Here is what bend is needed.Thanks Olliver/Rustbucket for next few pics.I have taken from his build.

I already have discussed the difference of RHD and LHD

Rest of exhaust is same in RHD and LHD.

Something else arrived (present):wink2:

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nice build, out of curious, so what you do with the leftover parts?
nice build, out of curious, so what you do with the leftover parts?
Ha Ha. The left over parts are not much.The CRZ engine with mounts,ecu and wiring. and IMA battery and cable. All laying around in home. Wife has given me deadline of one month to clear them. So lets see 0:) I have sold IMA battery to someone for free.
The engine no one wants because its too complex to swap it into a non hybrid etc etc.
Other parts if some one wants,just Pm me. Intake,wiring,ecu,axles etc etc

Meanwhile the headlights project completed

The are RGB but i like red.I will try other combinations when i get some time. The camera doesn't grap the whole look of them when they are lit at night.I reality they look very nice.
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Evaporative system(EVAP) and Fuel level Indicator Fix
(Read Update at end,3jan,2020)

As we know EVAP system regulates the pressure inside fuel tank and so the fuel level indicator on the dashboard work accurate. As now the fuel tanks are made of plastic so if for some reason the fuel tank is shrunken the fuel level will rise and the indicator in the dahsborad will show more fuel than actually is in the fuel tank. This situation can happen if the EVAP not not working properly and the fuel pump keeps pumping fuel creating a vacuum which caused the tank to shrink.
The opposite will also happen if excessive pressure builds if EVAP purge system is not working.So the fuel tank will expand and the fuel gauge will read less than actual fuel.

For the K-swap,the OEM CRZ EVAP purge valve directly bolts on to Cvic si wiring. So what the problem ?
Problem lies in flashpro.When the ECU is flashed with a 'race callibrations'(Map based,which we will use mostly on a swapped k-series engine) than the fuel level indicator on dash will not work accurately. There are several complaints over the net
I am linking some here,here,here,here here

but Hondata has refused to solve them by saying its a minor issue and people should not use race callibrations on street car(what a lame reason)
Here is some pic showing what it looks like.

The K-series came with lot differnt evap valves. Just use your OEM CRZ one.

Here is how i setup mine.Just mount the vlave somewhere suitable and connect the hoses.

CRz EVAp cannister is shown down below which is under the car. In my Honda Fit its big one inside engine compartment.Below is picture of my Honda Fit k20 EVAP system.Look how big the EVAp canister is.

So for normal k-swap users your work is done here. For users who still want to use Flashpro and its 'race callibrations' read the solutions below.

Aftermarket gas caps that hold pressure but allow inward air still suck the tank in, but will release once the vacuum over comes the caps vent check valve.

2: Use AFM or hybrid callibrations: drivability is a lot smoother in AFM/Hybrid callibration.So if ypu dont want to boost your engine in future stick with these. So if you choose this route, you will need MAAF sensor. So order one i have linked already and wire it as shown in wiring section.

3:Ktuner: Its cheap and has almost all functions.

5: Vent to atmosphere under hood. Some time smell of fuel comes in cabin and also not solves the problem completely (may not be legal also)

6: Return fuel line. solves the problem but expensive and overkill until you want to boost upto 500 hp

My recommendations are K-tuner route or flashpro AFM/hybrid callibration.

Found another solution(Jan 2020)
there is a manual evap pressure controlled device mounted on EVAP cannister.
Just unclip this hose and put some filter on it.This is located under fuel cap side of car.behind the rear axle and Tyre.

This pic shows some ghetto method and a custom foam filter :p

If you suck air,it allows from one end,but if you blow out,it let go after some pressure. Remove it by unbolting two screws,it has labeled on it as to which pipe will connect to fuel tank.the other pipe you need to vent under hood or under car etc where ever you want. i mounted it near brake reservoir and attach a filter too so that it will not suck dirty air into fuel tank.

Or this type of filter which comes with a boost solenoid.

So now fuel tank gauge works normal. what ever you use,ktuner or hondata flashpro.
So this covers almost all the technical details one will face in a k-swap crz or a Fit or a modern Honda.
A Tip: To burb coolant system of extra air i have found this very useful. When putting coolant in radiator remove this hose,as the coolant goes in the system the air escapes from here.keep adding coolant till it comes from here.

If not done by this method the air inside the system will circulate once engine is started,than engine should be shutdown and waited for coolant to slightly cool down,than open radiator cap carefully with a towel on it. Lets the extra air escape. Than again add more coolant.repeat the cycle again. So it takes few cycles of this. But with above hose removed,it takes just one.
I will update 1st page with total cost and the links to the pages for easier navigation.
As we know the online picture with time get deleted. So for ones who want to k-swap in future,you may save this thread offline. I have saved uptill now and have placed it in my dropbox shared folder.(for some reason firefox/chrome are not saving the pics but Internet explorer does nice job)

Google drive


Next i may post the other stuff like exhaust, wheels,supercharger etc etc
Note: If you want to install coolant temperature sensor in upper radiator hose,its adapter size would be 32mm(TSX upper hose)(CRZ OEM upper hose has 28mm adapter size)
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The height

As IMA battery is removed which is near 80Lb(36kg,yes i have weighted) so the rear is lifted and looks ugly.Almost 2 inch increase in rear height and half inch decrease in front height.

So use some lowering springs in rear or coilovers.
I had my Fit Tanabe Coform-R coilovers laying around so i used those. As the height is different so instead of shocks bottoming out i used spacers.

And here the K-RZ is ready

Do remember to do a clucth pedal its new engine and transmission now,so the engaging point might have changed. Also do remeber to do valve adjustments after 1st 1000 km
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Lets do some "looks" shall we ?

Been busy with the "Looks" now. Rear Bumper cut and Guaze fitted.

Been trying deiffernt combinations

and now the paint job. Battleship grey mate color

Rear lights blacked out with paper and done

Next i will install those black cut plastic on the rear mesh guazes.
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Look good with that colour :thumbup:
k24Turbo sidwinder built

Been busy lately with the turbo sidewinder manifold customization.Atlast its complete.

Original plan was to supercharge but due to the recent increase in $ rate that will cost near 7400$. So i am choosing turbo route.
The turbo is big one T04E. and the clearance is excellent.Just need to tug by wiring

Pure SS manifold and whole exhaust system

I am waiting for intercooler,injectors and some minor parts. I will convert to return fuel system. I will share that build too.
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Hi what intake system you had with original engine?
Hi what intake system you had with original engine?
Stock intake.But i do have HPS short Ram intake if you are interested Pm me.
I have been getting Pms regarding wiring diagram. i already have posted every detail. Its on Page 4&5 of this build.
I already have updated the 1st page with links to all the pages and detailes
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Intercooler and piping

I know its been while i updated my build its because i am waiting for my cermatic coating header paint to arrive from USa,it takes 1.5 month to reach here.
meanwhile regarding the intercooler piping there is no space from engine belt side to pass a pipe so i had to import an intercooler who has same side In and Out. Now the pipes will pass under the headlight.

But CRZ has plenty space behind front bumper,you can fit two intercoolers and still fit the bumper easy.

2nd reason for delay is i was busy with my Honda Fit build.Its also going turbo but the space is too tight behind the bumper.So i converted from a full size radiator and AC condensor to half ones.So far its works nice but we will see in summers how half radiator and a small Ac condensor works.(now AC condensor has a fan so i hope it will work ok).

AC condensor has slim fan as the space behind is tight. Radiator has a full shroud fan behind.Its a two row radiator.
Now i have much space for intertercoolar.(remeber this is Fit,not the CRZ in this pic)

Clearance of Ac fan.(i have similar fan on CRZ becasue space behind that is also tight)

Planty space behind radiator fan on transmission side.its a full size fan.Both CRZ and Fit has planty clearance here.

I i hope my ceramic paint arrives this weak. i am so keen on starting the CRZ.turbo feed has been installed in oil sandwitch adapter.

Meanwhile the garage looks like a mess.

I also have updated Dropbox folder regarding all the offline save of this build upto page 7 of this build.I advise download and save a copy of that becasue some time pictures get deleted from hosting sites.
Dropbox folder
Select option 'Download" on top right corner and it will download as a Zip file.extract and open.its 128 mb download uptill now.
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Thanks for the files!!

Btw, do you know which hasport mount suitable for K20Z2 on CRZ? I'm thinking to go budget K-series and frank the head with k20a3 or 4piston head.
5 speed RSX/Ep3 transmission also works

Thanks for the files!!

Btw, do you know which hasport mount suitable for K20Z2 on CRZ? I'm thinking to go budget K-series and frank the head with k20a3 or 4piston head.
It does not depend upon the engine you use.its more dependant on transmission you use as two HAsport mounts bolt to the transmission.On using k20's engine blocks you may not need the side CR-V side mount bracket. but using any other or a k24 block may need use of that side bracket.i already mentioned in initial posts.Rest k24 blocks are 1.5" taller than k20. No other difference in sides.

Now i remember i installed k20a3 ep3 5 speed tranny (base RSX aslo same) and it was also bolt on.
So now we have another budget option. Instead of using expensive LSD tranny of k20z3 or k20R trannies which cost bnear 3000$ , you can use base rsx 5 speed tranny in only 800$. and more beauty about that is it will work with CR-Z oem shifter and cables.
For 6 speed lSD one you need type R shifter and cable or a 6 speed Accord v6 engine manual tranny cables.So it also saves all those costs as well plus the labour.
Only thing we had to mdoify was just trim a metal peice as one cr-z shifter cable was an inch shorter.
This also applies to Ge8 Honda Fit aswell as Gp4 Fit hybrid.
another thing we found that Cr-Z shifter is a bolt on on Ge8 Fit (even though the Fit was CVT to begin with :smile2:)
we are using RPD-6 5 speed trasnmission which by internet is equivalant to base rsx/ep3 5 speed manual transmission. It has longer gears and also longer final its much smooth. i love it.
i installed it because with turbo i will need longer gears.

After trimming the metal

we had to custom make a small metal bracket to lock the clip holding it.

Another view

So here you have it,another couple thousands saved in k-swaping the CR-Z/Fit:wink2:
i think now its doable in even 4000$ or even less..
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Nice info there.. I never know the 5speed gearbox on CSX & JDM FD base have the same shifter and shifter cable as OEM crz.

In that case, the hybrid racing's short shifter for crz should work on the 5 speed k swap probably.
Nice info there.. I never know the 5speed gearbox on CSX & JDM FD base have the same shifter and shifter cable as OEM crz.

In that case, the hybrid racing's short shifter for crz should work on the 5 speed k swap probably.
The Type R and Civic Si shifters are different becuase their gear lever works dirrently when going in 6th and in reverse gear. we only changed the 5 speed tranny first and hoped that the already installed Type R shifter and cables will work but the 6th and reverse were opposite and other gears were also shifting in lelf-right manner rather than front and back. We did not had any other thing laying around and finding a compatible 5 speed shifter would have taken days because we dont have this car/engine here.
So as a last option we tried and installed the CRZ shifter and calbles and every thing works like charm.
Although the CRZ shifter is a 6 speed but it works just fine,but has no 6th gear now. So dont worry that how the 6 speed CRZ shifter will work with the 5 speed transmission 0:)

So now if we want to use CR-Z own shifter we do not have to use Accord V6 manual 6 spd transmission. We now have cheaper alternative.
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Ceramic painting headers and downpipe

Hello guys,its been a while i updated. Was waiting the ceramic coating to arrive and now its here.without further delay

I am using VHT flameproof.
and downpipe also

In a turbo setup you cannot over do heat insulation.the more the i coated them outside aswell as inside.

Dried with dheat gun and now curing under sun.but real cure will be when the car starts and they warm up enough

Meanwhile the carbon hood arrived from Japan.

Plan is to install the trubo and all exhaust piping and start it.check for any leaks etc etc. after that install the intercooler piping and oil catch can,all the vaccumm pipes etc.
So i hope to start her in a day or two InshaAllah :)
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Intercooler fitting and piping

Hello, i have been busy with intercooler and the piping. I used universal piping.

You will need a cutter and a grinder if you want to do this D.I.Y

It took all my sunday from 12 pm to 12 am. i also installed Hondata 4 port boost solenoid

Trial and error

had to take in mind the bumper fittment and head light clearance

The pipe whihc is cut doest have beaded end any the coupler may i used a pliar and modifies it to make the beads over the cut ends. Here is a youtube link to a useful video.

One 90 degree bend was used a s such. Other i had to cut a U bend to half. and some staight pipe part.
with same In/Out intercooler there is lot less piping needed which will help lot reduce turbo lag

here is final product

I used a thick metal plate and drilled two holes in it and bolted the intercooler with front bar.very solid

had to shave off some metal

When ever you cut/shave metal,to avoid rust, paint it. i use this clear coating from Rustolium.

Now the piping is so short as you can see

Hood clearance is also excellent

Also clears my self made rain guard

Some of you may have noted the welded SS pipes.

Its to further reduce the number of silicon silicon coupler flex and expand (at high boost).
So when i got all the sizes,i made SS steel piping of same and welded there are only three coupler cold size and three on hot side of piping.
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Hondata 4 port solenoid and PCV catch can

The bumper clearance is also excellent. You could fit a cat in front of intercooler and it wont tough the front grille.

The cahrge pipes also have planty space between the bumper

Hondata 4 port boost control solenoid:
Since i aim of near 550 hp so traction will be issue in 1st gears. thats why i installed hondata 4 port solenoid,so i can control how much boost i want to each gear.

Its light weight,so i used a cable tie and bouble sticky taoe behind to fix it

Oil catch can on PCV
Since it boosted now so the crank case pressure will be more and there would be no vacuum in the intake turbo seals would blow the oil out and fail.thats why its now must to vent it to atmosphere or into exhaust with venturi device but i opted for simple approach.

its a simple device i ordered from aliexpress/ebay
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Hey, where did you get this bumper from and how much did it cost u?
Hey, where did you get this bumper from and how much did it cost u?
Which bumper are you talking about ?
Back ?

Or front ?
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