SW20 k-swap FAQ
Q. Cannibal vs full kswap
A1. The "Cannibal" utilizes the Toyota E153 (turbo model) transmission with a k20 or k24 using the adapter kit by Hux Racing.
A2. The "Full kswap" will use a Honda k20 or k24 motor and k20 transmission with the motor mount kit from Hux Racing. We have solid and poly versions.
Q. Why the two versions of kit?
A. We offer an adapter plate to use the Honda k20 or k24 with the Toyota E153 transmission. This transmission has proven itself nearly bullet proof at 700whp levels and has survived in the high 800whp zone. The Honda transmission by comparison will simply not survive even at stock 200whp levels when placed midship with the traction this layout offers. We do offer a mount kit for full kswap guys who already have or are looking to purchase an aftermarket gear set for their Honda trans and besides, there appears to be many Civic kswap guys looking to make the chassis switch. This being said, numerous all motor guys are doing fine with a stock k20 trans.
Q. Do you have a plug and play harness for the sw20 k-swap?
A. Hux Racing has documented how to perform the wiring yourself. Check the Database section of this website. We offered a plug and play service in the past and have greatly simplified the process over hundreds of harnesses. We share that knowledge with you.
Q. What ECU can I use.?
A1. Hondata-KPRO probably the first choice if using the Honda trans since you will be able to use the honda speed sensor for launch control and boost by gear. You will need to address the dash speedo issue at this point. You can check here for ecu compatibility. https://www.hondata.com/tech-rsx-ecu-reference
A2. AEM Infinity 506-this is the ECU I purchased for the first build on my personal kswap sw20 . I used the ka24a4 harness and pinned it to the AEM connector. They also sell a pnp patch harness for rsx k20a2 pinout.
A3. Haltech PNP for the RSX-another good option as it is set up for the k20/k24 and gives you the ability to swap speed sensors( good for either trans choice)
A4. Fuel Tech is really gaining popularity and now found on the fastest Turbo SW20 in the world.
A5. My Personal car is now on a Link Thunder.
A5. You can use any ECU you prefer to control the K. The SW20 wiring is pretty nice in that the motor wiring is fairly seperate from the rest of the chassis wiring. This makes building your own harness far less complicated. A kswap harness with relays for a Civic could be made to work. See out wiring How To.
Q. What do I do about the radiator lines?
Left side hose
A1. Tractuff is the goto for water necks whether using Toyota or Honda transmission. There are numerous cylinder head styles and outlet positions available from Tractuff.
A2. You can delete the j-pipe on this side and use a Gates 22703 hose to run from water neck to hard line under car.
Right side hose.
The lower neck will require shortening of the under car hard line to simplify the coolant hose routing.
A1. Point thermostat housing downward and use a universal flex hose from part store.
A2. A 2' universal flex hose from the car parts store can be used to make the lower radiator line connection without modifing the factory hard line.
Q. Heater lines ?
A. Simple ,the k will have two heater bungs just like the 3s or 5s you removed.
B. TCS sells a heater line kit for the 3sgte. It works great for the K.
Q. What do I do about axles?
A1. The Cannibal swap with theToyota e153 uses the stock turbo axles and nothing custom is needed.
A2. The full kswap with Honda transmission will need to source axles from www.driveshaftshop.com . They sell the 5.9's AND 2.9's.
2.9S Part #s RA90-43X2 and RA90-44X2
5.9s Part #T020-HUX The 5.9s are a kit and include upgraded outer splines and hubs.
They are also DSS Pro Level axles for those looking to make record attempts. At this time all 8 second SW20 are on DSS axles.
A3. Cheapest route but please read all: The n/a mr2 and the civic/integra share the same axle spline count. This is a cheap solution doing a full kswap with k20 transmission on a Non turbo MR2. O'Reilly's (HO-8003) drivers side, (HO-8121) passenger side. Thanks James White for part numbers. Please be aware that there will be very little thread engagement on axle nut due to splined end being short for MR2 use. If you have fitment issue on inboard diameter you might need to confirm part store supplied correct axle.
Q. How do I plumb the clutch hydraulic line to the Honda Trans. ( full kswap only)
A. We got you Boo. Hux Racing sells a clutch line.
B. If you have an auto SW20 and are converting to manual, TCS sells a long clutch line that runs from the master cylinder to the slave cylinder.
Q. Will I have to modify my trunk wall to make this work?
A. No, neither kit version requires sheet metal cutting.
Q. What do I do about an exhaust ?
A. You will need to fabricate some plumbing to tie into your exhaust of choice. Most MR2 exhaust systems have a flange at the crossmember and you can easily tie your header or down pipe into it. The sidewinder turbo manifolds found on Civic kswaps has been shown to work also. The stock header found on the k24a2 and k20a2 will fit in the engine bay.
B. All motor. I recommend going k24 as the ktuned long tube for K20 EP3 use will just clear the MR2 crossmember. The taller k24 deck height gives better header clearance.
Q. What do I do about shift linkage ?
A1. The Cannibal kit uses the existing Toyota E153 trans and will need no custom shift linkage.
Q. What about air conditioning?
A. There is plenty of room to mount the Honda a.c. compressor. You will need to have a custom set of lines made. Find Keith Ly on the kswap da works facebook group. He has sold custom lines.
A1. Wiring: Please not the k series engine harness does not have the a.c. clutch wire. It is in the radiator fan harness. Not an issue really as the SW20 uses just a single a.c. clutch wire to the engine bay. See our wiring writeup. You will need to use a tach adapter to feed a factory Toyota tach signal to the dash wiring as this feeds the SW20 a.c. amp.
Q. Power Steering pump delete from k series?
A. Ktuned makes a power steering pump delete kit for the k20z3 accessories. It will require a special version mount for timing chain side of engine. Reach out to us.
Q. What about the fuel system.
A1. All Motor. The factory fuel rail is returnless. There are 2 ways you can do this. Run a GM C5 fuel filter/fuel pressure regulator and a fixed 60psi. This would allow you to run the stock honda fuel rail in an all motor combo. Or, run a conventional regulator between the factory sw20 fuel filter and return thru factory return line.
A2. Boosted combo. An aftermarket fuel rail like Hybrid Racing sells, and fuel pressure regulator will be needed. You can feed off the stock mr2 fuel filter with an m12x1.25 to #6a.n. fitting. The factory Toyota return line is a simple hose barb.