KJ 2.3

[TsiMiata]

Consider the ZE in my car came out of a millenia and the KJ also resides in the same car. If it fits in the millenia, it should fit no trouble in an MX-3.

The two big problem areas with this swap are the intercoolers and the ECU. You will have to custom plumb an intercooler, no doubt about that. Then there is how are you going to run the engine. None of the plug in mazda ecus will work. Even if you go through the trouble of wiring in the KJ ecu- which will be a huge undertaking - your stuck with an automatic transmission. The only way I see around this is to run an aftermarket ecu. You've got to ask yourself if you have the $$ and the knowledge to handle something like that.

Someone mentioned your tranny not holding up to the power. With the addition of a brace available from cyborg zero it should hold just fine. Just don't go doing any 7,000rpm clutch drops.

[Zoso124]

Originally posted by IanL:
Isn't it true that the MX-3 gearbox is the same as that fitted in MX-6s and V6 Probes (with small ratio changes), and that people have boosted those cars to over 210 hp and probably the torque of a KJS? Maybe the gearbox isn't that weak at all.

The KJ Auto is a completely different beast. I can't see a G5M-R handling 200 lbs of torque down low for too long.

Also the tranny saver that Cyborgzero developed was designed for PGT/MX6 and from speaking to Rob we've found that the rear mount is completely different on the MX3 and thats why we don't have as many tranny issues as they do.

[papa roached]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7906704050&category=33615

looks like it would be tight on the backside of the motor and you would have to do some fab work on plumbing and also looks like it might be tight on height like has been said

[IanL]

Sounds like this topic is getting serious.

As far as the ECU is concerned: Someone on Probetalk has fitted a KL62 ECU (Millenia + KL engine + ATX) to his MTX OBDII Probe/MX-6, and the only issue it seemed to throw up was fault codes for the non-existent ATX solenoids. He was going to look into simulating them with suitable resistors. Now you wouldn't expect the KJ Millenia to need to be very different in the ATX control area, so using the KJ ECU may be no more difficult than that. Need to get some confidence in that by comparing KJ and KL wiring diagrams for the Millenia, which I just happen to have on that CDROM I keep on talking about. I'll do that when I get some time.

However, there will be a big rewiring job if the MX-3 is OBDI, and there is also a small amount of wiring for the MAF, detailed in the Probetalk thread http://forums.probetalk.com/showthread.php?t=1701090811&highlight=millenia+vaf

[IanL]

Originally posted by Mariusz:
Hello, I received today reply from one of our (Polish) tunning groups. Just in basic translation mail has included info:

We can install KJ in MX-3 for 400$, KJ and K8 have the same engine mounting points(bolts).
You can leave yours stock MX-3 gearbox. The rest of the elements should be from KJ.

Now i don't know is it hard to switch them or not. 400$ is not a big price. Also i don't know if they are telling the truth.

Mario,
If they've already done it, why don't you ask them to put you in touch with a satisfied customer? That way you could see the completed job, or at least some photos, and get that person's views on how good a job they've done.

And you could post all that here

[mmx01]

This is a good idea, I will ask about completed swaps. I see that the amount of troubles according to this swap is still increased by next posts. My MX-3 is probably ODB I i don't have HOLD lamp, there is a HOLD lamp in the dashboard but it never worked. If I will put my stock gearbox to KJ i must emulate ATX solenoids to prevent errors occuring on ECU ?
And the most important question is, how big wallet should i have to complete this ?

KL-ZE swap: (International shipping,taxes etc)
Engine 1100$
ECU 250$
Shipping: 500$
Swap: 270$
Tax: ???

KJ swap: (All done in country)
Engine 1500$
ECU: ?
Shipping: 0$
Swap: 270$
No tax

[IanL]

Originally posted by Mariusz:
My MX-3 is probably ODB I i don't have HOLD lamp, there is a HOLD lamp in the dashboard but it never worked. If I will put my stock gearbox to KJ i must emulate ATX solenoids to prevent errors occuring on ECU ?

You will be OBDI if your MX-3 was built before 1995, and maybe if it was early '95. I'm not sure what you mean by HOLD lamp, isn't HOLD a control to stop ATX changing gear upwards? Are you perhaps thinking of the Check Engine Lamp (CEL)?

The person on Probetalk who fitted the KL62 ECU hasn't yet discovered whether the effect of not having the ATX solenoids is only to produce fault codes, or whether it also affects the performance.

[mmx01]

My mistake , you have right I'm talking about CEL. My mazda is from end of '92. Is there a big diffrence between ODB I/ODB II wiring ?
Here in Poland cars prices are diffrent, my Mazda is worth 4400$, in US probably 2000$ (it is in very good condition this is the reason why I want to tune it up instead of selling)

Reg,
Mariusz.

[IanL]

Originally posted by Mariusz:
My mazda is from end of '92. Is there a big diffrence between ODB I/ODB II wiring ?

Yes, OBD1 connection to ECU is with 3 plugs, OBDII uses 4 plugs, see this thread for more: http://www.mx-3.com/ubb/ultimatebb.php?ubb=get_topic;f=15;t=004240#000013

[mmx01]

This swap looks like mission impossible.
My point is that I deeply doubt about the knowledge of this tuning group. They probably don't have any idea about this ODB issue.
I've finished a electronic high school so probably I will rewire ODB I to ODB II with the proper diagrams correctly but... I don't have a garage so I can't swap the engine by myself.
At the end the problem can occur and what will be next steps ? tuning group will say we've done everything correct but the engine don't work probably because of wiring the ECU, I will say I rewired ECU correctly probably there is something wrong with engine... HELP ME, what to do ? My ECU is 100% ODB1 as I see all KL-ZE are ODB I compilant and working great with KL 36 ECU.
Probably there is no KJ ODB I ?


Reg,
Mariusz.

[Custommx3]

Youd have to have the harness and the ECU anyways though. Because one, its setup is so much different than any K series motor, and probably has more sensors too...

[IanL]

Originally posted by Mariusz:
Probably there is no KJ ODB I ?

The full story goes like this: The KLZE Millenia uses the KL62 ECU. Now, despite the fact that all Japanese Domestic cars are OBDI (they don't use OBDII in Japan), that ECU uses the same 4 plug connector system as OBDII cars. So I have assumed that the same is true for the JDM KJZEM ECU. It is certainly true for the export KJS Millenia, because I have the wiring diagram for that.

So I would expect that, even if you got a JDM ECU for the KJ (which would be OBDI), it would not help, as it would still require the 4 plug harness.

I think you have very accurately described the risk you would run doing the swap, if you did the rewiring. But if these guys have already done the swap, maybe they did it to an OBDI car? Just ask them whether they had to rewire the harness to 4 plugs; see what they say.

<small>[ June 21, 2004, 06:14 PM: Message edited by: IanL ]</small>

[IanL]

Originally posted by Custommx3:
Youd have to have the harness and the ECU anyways though. Because one, its setup is so much different than any K series motor, and probably has more sensors too...

There are dfferences; e.g. the KJ has two air bypass solenoids which the KL doesn't have, three air temp sensors instead of one, and no VRIS solenoids. That's just a quick look, there may be more, but its 0030 here, so I'm off to bed

[mmx01]

I've spoken with them and, they probably know what they are doing. They have a electronic guy on site.They also try to find informations about:

1) Is the center of gravity between K8 and KJ the same ?
2) Is there a chance to having troubles with position of "i don't know if this is proper word for this part" semi-axle ?, they should be in stright angle according to the engine. They have doubts about that the same location of mounting bolts is guarranty of this.

As the example of a hard swap which they have completed is swapping a VTEC engine to a non VTEC car with all sensors harness and others.

Reg,
Mariusz.

[papa roached]

ummm, any honda swap is easy as cake, so dont take that as a "hard" swap example :p