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K Series Engine Swap Research

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6.8M views 2.3K replies 159 participants last post by  mcmcmc  
#1 · (Edited by Moderator)
Last Update: 3/12/2014

"Getting closer and closer, Thanks to all who are helping make this a more manageable task for others"
Mounts: Solved
Shifting Mechanism: Solved
Axles: Solved, Updated 3/12/2014
Wiring: Researching, Updated 3/12/2014
Radiator Hoses: Solved
Heater Hoses: Solved
A/C: Pending Updated 3/12/2014
Throttle Cable: Pending Updated 3/12/2014
Fuel System: Solved
Exhaust System: Solved, Updated 3/12/2014
Anti-Lock Brakes: Solved
Power Steering: Solved


General Info: Always Read First...!
Well, I have been gone for a long time and will try to keep this updated. Sorry about the delay as I am in a transition period and can't work on the swap.
Also some really big information the innovative mounts put the engine so far forward that only the PRB intake manifold off of an RSX type S will fit.

BottledFedMR2 has confirmed this and it's been verified. So anything else will require the firewall to be cut or the manifold to be shortened. This sucks but at the same time it's nice to have the engine weight as far forward as possible as it puts it more centered.

I will have CONFIRMED next to everything I know for 100% is correct information.

Mounts: CONFIRMED
Recommends 75 was told by innovative that it's the same as a 65a poly used by
other companies. Theirs is pure poly so 65a could sag over time.
http://www.innovativemounts.com/ProductDetails.asp?ProductCode=90551

Shifting Mechanism: CONFIRMED
Use the Factory MR2 cables and this bracket will make them interface with no other mods.
http://www.innovativemounts.com/ProductDetails.asp?ProductCode=50507
**Note: 2006+ Civic SI transmission will require the shift "Arms" off of an RSX type S transmission. You will then be able to
hook up the innovative shift Mechanism as it would be on a normal RSX-type s Transmission.


Axles: CONFIRMED
Axles can be ordered through Drive Shaft Shop they now have part numbers on file though they are not on their website.
Part Number: RA9040x2 and RA9041X2

Wiring:
There is much debate about the wiring so far it's every man for himself. I haven't actually started the physical wiring so I can't confirm anything or have a proven design. There are a few that have completed their swaps and have them running and driving but they all sort of do wiring differently. Monkeywrench racing is working on a full swap kit and will be selling the parts all separately. I talked to them and they will be offering a wiring solution. Right now this is known for a fact!

If you want the car to fully function like a stock spyder you will need to shotgun the ECUs (Factory Toyota ECU and Honda ECU) if you don't care and want to replace your cluster then you can run a straight Honda ECU but don't expect it to be very easy and you will need to know wiring to do it. You will also find it a lot harder to get the A/C running correctly without redesigning the whole A/C wiring system.

Now if you just run the Honda ECU by itself and keep your factory cluster you will lose your TEMP gauge and a few other idiot lights.


Old Info 3/12/2014

ABS:

I have found in theory that the ABS is almost completely independent of the engine control unit there is one wire going to the ECU and from talks with people its a input to tell ecu that ABS is active.

P/S:
The P/S system isn't too much of an issue in my eyes as it will keep running if you don't give it any signal from ECU. So at the basic level, you have P/S no matter what. Now if you want to operate factory style then you need to configure Kpro to see the signal from the pump to IDLE UP on the current draw which is PIN E3-25.

There is also a pin on the ECU for turning the pump on and off while the engine is running/off. This pin is E3-19 on the ECU. From what I understand if the Power Steering ECU doesn't see any input on this pin it will just stay on all the time with the car in ACC/ON position. As for any speed variance to Pump pressure adjustments, this is all done between the P/S ECU and the ABS ECU (as the ABS ECU supplies the speed signal).

A/C:
I am working with innovative and when I start my swap will be using a prototype A/C adapter plate. You will want to keep your 1zz compressor as it will be the easiest by far to adapt to work. The K-series compressors are bigger and right now the 1zz one will barely fit.

I will be running wiring straight to the HVAC controls so that I can bypass the Toyota multiplex system and in essence just hard wiring the functions like Honda has in its cars all the way up to 2002. I will be recreating the same system they used in the earlier model civics that did not require any type of digital electronics.

At the back of the Toyota Hvac controls the A/C switch comes out as an analog +12 or Grounded signal that goes to the combo meter where it is processed and sent to the ECU on a multiplex. I will just be wiring straight to this output on the HVAC control and cutting the meter and associated multiplex functions out of the circuit. I will then create a patch harness for the A/C compressor that contains the High/Low switch relays to cut the clutch and also figure out a way to wire a freeze-out switch into this same harness.


Unless I am missing something and by all means correct me. I see that if you completely remove the factory Toyota ECU the only things that will not work are the A/C, Temp gauge, and Some idiot lights and that is it. Everything else can be wired/jumped to function like normal.

The Temp gauge is on multiplex along with some of the idiot lights and A/C. You could make these work using the factory ECU as a multiplex conversion box and feed it the K-swaps sensor signals and hope they are in the same range as factory Toyota's or hook up factory Toyota sensors in addition to the Honda ones on the engine. IE: two oil pressure switches, two temp sensors ETC...

My goal is to make it as streamlined and simple as possible (Wiring/Electronics). That is why I want the Toyota ECU to be completely gone and all functions controlled by the Honda ECU.

Overall I am getting more and more done day by day and hope to start buying parts soon. I wanted to figure out most of the wiring before I even took the first bolt off the car. I'm hoping to have some of the conversion harness already made before I even start working on the car. "


Throttle Cable:
Was informed that if you buy a Cruise Control delete it will allow the factory cable to bolt in no major mods are needed. Getting verification but should be for a 00-04 RSX.

Radiator Hoses: CONFIRMED
He also said that the K-series and the 2zz are very similar in where all the hoses route. Since this is true He has confirmed the fact that in the swap in the lotus all the hoses fit up 99% perfectly.

He said cutting one hose 2 inches is all that is required on the lotus. Since the engine is what determines the placement of hoses then the spyder should be no different than what's required for a 2zz swap.

Heater Hoses: CONFIRMED
Read Radiator Hoses Same applies.

A/C System:
Again BottledFedMR2 is the guy to see, he is working on bringing an A/C bracket to production. He is close to having it ready and I myself will be buying one.
It will use the 1zz compressor, he says it will be a little lower than he would like but it doesn't seem to be a big issue.

Tim said they are in the works to make a bracket for the Lotus with Kswap. So He says he doesn't see why the spyder wouldn't be able to use it. Again like the throttle cable he would need someone to test fit it and confirm or send it back to have it modified till they get it right. But it is doable and not a big issue.

The Lotus has issues with A/C line clearance and he said that is one of the problems they are working on. When I asked him if the Lotus and spyder have very similar bay layouts I didn't know for sure but he said the way the firewalls are the spyder might actually have more room for the lines. Like everything though he can't say for sure.

Exhaust System: CONFIRMED
PPE makes a Header now for MR-2 Spyder with Kswap and is also available through MWR.
The collector size is 2.5" and the overall header is longer than the stock one so will stick out further than the factory.
Still waiting to get info on if you can use a downpipe to make it line up with the rest of the factory system.

Fuel System: CONFIRMED
You will need to run a return of some sort. You will need to also get a fuel regulator. I am still a little iffy on this from a basic swap standpoint because Honda uses a returnless system factory so you might not need to do this if you're just going to OEM performance.

Extra Notes:
I will update this a little more in a few days. I wanted to get something new on here as I have been away from the forums for a while and people might like to see a summary of the events going on with the Kswap. The main thing that is missing is the wiring. Once there is an agreed-upon design that everyone thinks works and is simple as it can be will the swap gets easy enough for everyone.
 
#815 ·
What transmission options are available that will work with these axles and a k motor? How do those transmissions handle road race abuse? Are there any transmission options for high power (500+) output?

I'm also considering a 2gr-fe. It works with a proven transmission, and I wouldn't have to explore new territory to get big power.

Or I can stick with the 2zz. Might be more expensive in the long run if I go through motors, and I will probably never realize 500+ whp with that motor.
 
#816 ·
I'm currently running the z3 tranny. No issues other than needing shifter mechanism from rsx. This was explained pages ago btw.

I forgot which company but they make a race sequential tranny with straight cut gears. Other than that a few company makes gears and such. Just check boosted sections on honda forums about what they are using for high hp.
 
#817 ·
Correct, I have a z3 trans in both cars. You will need a 02-04 type s shifter mechanism to reverse the direction of the shift cables in our favor. You will not need the vss sensor of speed sensing ring as long as you use the toyota speed sensing system. As far as trans option there are a ton of options. Rsx, accord, tsx, crv and civic all had manual transmission that will mount to the k blocks. There are different gears you can swap in and out for different ratios. Stock civic would not hold up to 500hp for a lifetime of beating. I have an account with syncrotech who makes updated parts for the trasmissions including carbon fiber synchros, this is what I run in my transmissions. You can also run crv gears and run the trans comfortably at 500 whp. I know alot of guys at higher hp are running truck gears. Also you can rebuild or swap parts from these transmissions in your garage. These arent like c56, c60 etc which require gear pullers. Once the trans is on the table you can do a complete rebuild from start to finish in 4 hours and have the car back on the road. Z3 is nice because it has a factory installed helical LSD but lsds are almist half the cost when compared to the c transmissions. I think the honda quaife is like 700 new
 
#819 ·
No gear pullers to dissemble a transmission? God, I love Honda. I can't find any "z3" transmissions on ebay motors searching for "k20z3 transmission" and "Honda z3 transmission." I only found ONE rebuilt for $1,600. How do I find this thing?

I think I'm sold. Instead of saving for a 2zz, I'll see about saving for a K24, swap kit, ECU, and header. I might just have to get a 2zz for now. School starts next fall, and summer is my last chance to drive at Laguna Seca for 3 more years or so. I guess what I do depends on how many pennies I can save by spring, and how much I might get by selling 2zz specific stuff.
 
#825 ·
I think you need a huge budget to build a 500hp track car with a spyder. No stock block K series engine is going to live with the heat and abuse on our tracks here. Yes the K series are stout motors but heat generated in a rear mid engine application is worse than front engine. Even front engine 500hp K series road race cars are very rare while being easier to build.

The general consensus is, boost sucks for track cars because of heat generation.

You can get a very fast car with the stock block k24 engine or a 2gr without all the headaches of 500hp build that never runs right or keeps blowing up.

I would pay the extra to go K24 over a K20 and keep the engine internals stock.
 
#830 ·
I took stock of what I have, and the K20 is going to be my post-law school project. I probably won't be able to afford an Elise right out of school, but a k24 swap sounds feasible. Then, later, I can decide on going FI, or switch platforms to something else.

As for now, I have too much invested in a 2zz that I'd need to re-invest for the K20xxx swap: clutch and flywheel, oil pan, custom exhaust, header, intake, ECU, etc.

But, I'm looking forward to the ks4a swap. That motor would be a monster.
 
#832 · (Edited)
I think the heat problem will be trivial with an open-top car. I am going to build an aluminum panel to cover the entire passenger side of the cabin, and in that build a NACA ducts that feeds air directly onto the motor (and intercooler) through the firewall, which I will cut a giant hole into. I will also make a partition to separate all that from my side of the cabin. Should be safe, and the engine will get just as much as as if it were mounted in the front. I might even be able to close the engine-side side vent to reduce drag.
 
#847 ·
I have an 04 civic si trans with LSD and I already fitted a rsx type s linkage to it....I'd sell for the right price but was hoping to trade for an S2K trans of similar condition. It has about 40-50k on it and looks new. Not doing a kswap into my mr2 anymore


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#848 ·
I also have the version 1 kswap mounts from innovative with the black bushings. PM me if you're interested in either. Just thought I'd throw it out there since both of these things are in the conversation right now


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