Mazda K Series with RWD

I think I have asked this before but I am not sure.  The Mazda K series of V6 motors has always been something that I have wanted to mess around with.  In particular the KJ-ZEM (miller cycle variant).  The reasons for that specific motor I can get in to later.  There is also the KL and its variants that at 2.5l is a tasty package that I am supersized no on has made a bolt in package to a Miata and had a boost option.  

Anyway does anyone make a adaptor plate that lets you bolt the Mazda K series motors to a RWD trans?  Last time I looked I did not find it but maybe some one has done it.   

There must be because I remember seeing on YouTube a Porsche 944 with KLZE with a turbo. Pretty oddball swap but he must have used something.

I would love to hear more about why you’re into that particular K motor.

For years I dreamt of a K8 (the baby 1.8 v6 from an mx3) into a stock 1.8 miata (so I can say its stock sized...) JUST for the soundtrack.  These K v6s make beautiful music.

There is at least one long thread on Miata.net where someone put a KLZE in a Miata. There are videos on YouTube, too. I loved how the KL in my old MX-6 sounded.

I once drove a car with the 1.8 V6 and it had a glorious sound. I would love to see one of these swapped into something cooler than an MX-3

I seem to recall a Probe GT V-6 that the guy went to great lengths to convert to rwd/longitudinal.

That's all I got

Smart-alec youtube video

There is plenty of KLZE Rwd info buried in this thread from the NZ Oldschool forum. V6 swap starts on page 3 after a detour with a rotary.

https://oldschool.co.nz/index.php?/topic/28896-was-yoeddynzs-1968-viva-mazda-v6-new-owner-welcome-guzzi-rat/

Smoking Tire video.

https://youtu.be/BwpJmIvSfDs

I’m quite fond of the soundtrack in my track rat, the Wu-Tang Financial ford probe. KL powered with some eBay headers.

https://youtu.be/Mol1I8mCN7w

There's a lady in the UK by the name of Clare who does a bunch of KL swaps and stuff, came across her on a locost build I was reading a while back. She has a website Crap engineering . Pretty sure she sells adapters via her Facebook, otherwise from memory she may be willing to supply a file to have an adapter made as opposed to shipping.

So why would I want to deal with the KJ-ZEM?  Well I like a challenge.  What Mazda did was to tip the intake valves up in the heads to they are almost vertical in order to alow for the supercharger to fit in the valley of the motor.  This then leads to an intake port that is almost strait down and the injector is firing almost directly at the back of the valve.  All of this is supposed to be optimal for a motor.  I don't think Mazda did ti on purpose as the intake was always going to be under pressure in the miller cycle version BUT inadvertently they designed almost the perfect intake ports in the heads.  This should lead to fantastic airflow in to the chamber as well as excellent fuel atomization with a greatly reduced wetting affect on the intake port walls.

Now some things I have been thinking about.  How convert a KJ back to an auto-cycle motor.  Well that is simple just have the cam ground down so the intake ports close sooner.  I have two local machine shops that specialize in cam work so getting this done is not a issue.  This also means I can modify a jnk yard motor with out taking the heads off  I just need to figure out what exactly to have the cams ground down to.  I could just match the profile of the KL.  I could se eif there is a difference in the JDM versions of these motors as they all the JDM versions seem to have a bit more HP and torque.  Research needs to be done on this one.  I have been looking in to if I could just use the cams from a KL but with the intake valves being indexed differently on the cam centerline this may make using KL cams in the KJ difficult due to getting them indexed properly and then there is the question of will the cam sprockets bolt up.  All questions I don't know.  Considering the rather cheep cost of getting cams re ground it just seems like the easy way to do it.  No guess work on interchange and fitment.  All I am going is shortening up the cam duration on the intake.

Another thought was to put KJ heads on a KL.  Again the cams would have to be sorted.  As for as I know You can swap the KJ heads on the KL but you can not put KL heads on the KJ.  The pistons in the KJ do not have valve reliefs for the intake valves due to them being indexed so the valve face is parallel with the top of teh piston.  One thing I don't know is the CC's of the KJ heads.  That is something I need to look at so I can figure out the static compression of the motor.  Thinking about this it may be quite high as they were regulating the actual dynamic compression with the valve timing.  In theory you would run a much small head volume due to the valve re clocking in the miller cycle and it not needing space for the intake valves to open.

Anyway I have babbled on long enough.  I just think it would be cool to make a auto-cycle version of the KJ.  More importantly I just want to do it for the engineering challenge of it.  It would be fun/different.          

wheelsmithy said:

I seem to recall a Probe GT V-6 that the guy went to great lengths to convert to rwd/longitudinal.

My only real complaint about the MX-6 was that it wasn't RWD. It could have used another 50 hp, too.

I think Tim and Tom should look at the Crap Engineering stuff and consider a K series Miata project. I know that there have been a lot of Miata projects but if for no other reason the sounds that a uncorked K series makes is up there in the top two or three engine symphony’s that I have heard. Just glorious noises and then the over run spitting fire.  As one Mr Clarkston said “I am having a crisis”.  

It is also an in brand swap. The red line is up there with the best of them. Also there is no Honda tax for the motor. These motors are cheep and plentiful.  

Did I mention the sound?  I would take a power hit just to get that soundtrack. 

In reply to BenB :

I saw an MX-6 on the road yesterday and remembered how much I like the looks of them. I found myself wondering about how cool a RWD engine swapped version with more than stock power would be.

T.J. said:

In reply to BenB :

I saw an MX-6 on the road yesterday and remembered how much I like the looks of them. I found myself wondering about how cool a RWD engine swapped version with more than stock power would be.

I see one around here pretty often. I like how the second generation looks a lot like a hard top 2+2 NB Miata.

I need this!!!!

dean1484 said:

I think Tim and Tom should look at the Crap Engineering stuff and consider a K series Miata project. I know that there have been a lot of Miata projects but if for no other reason the sounds that a uncorked K series makes is up there in the top two or three engine symphony’s that I have heard. Just glorious noises and then the over run spitting fire.  As one Mr Clarkston said “I am having a crisis”.  

It is also an in brand swap. The red line is up there with the best of them. Also there is no Honda tax for the motor. These motors are cheep and plentiful.  

Did I mention the sound?  I would take a power hit just to get that soundtrack. 

Does it have to be a K series, or just a Mazda V6 into a Miata?  We (Research and Advanced) put a Lincoln V6 (which is the same engine as a 6) into a Miata.  It was pretty cool to drive....

In reply to BenB :

I was thinking it looked a bit like an FD RX-7 with a trunk. 

alfadriver said:

dean1484 said:

I think Tim and Tom should look at the Crap Engineering stuff and consider a K series Miata project. I know that there have been a lot of Miata projects but if for no other reason the sounds that a uncorked K series makes is up there in the top two or three engine symphony’s that I have heard. Just glorious noises and then the over run spitting fire.  As one Mr Clarkston said “I am having a crisis”.  

It is also an in brand swap. The red line is up there with the best of them. Also there is no Honda tax for the motor. These motors are cheep and plentiful.  

Did I mention the sound?  I would take a power hit just to get that soundtrack. 

Does it have to be a K series, or just a Mazda V6 into a Miata?  We (Research and Advanced) put a Lincoln V6 (which is the same engine as a 6) into a Miata.  It was pretty cool to drive....

For my purposes yes. .. . .  Yes it does.   I am really interested in how a K series swapped Miata would compare to the Honda swapped one that was just done by or should I say "for" GRM.   Cost, ease of the swap and the driving experience could all be compared.  Ok may by not the ease of he swap since there is probably not a shop that GRM can take it to that specializes in this swap (like the honda swap). 

To me it is the motor option that they should have offered as an option when these cars were new. Considering how these motors are engineered it is almost like it they were going to put there but for some reason did not do it.  My bet is that the tax on cars over 2.0L was probably a big part of it and I am sure that the manufacturing cost of the I4 versus the V6 was also a factor.  I also think that at that time ford and Mazda were partnered and as such ford may not ahve wanted a V6 Miata as it would then have been a direct competitor to the mid level V6 Mustang.  What also has me interested is that the V6 in the Miata is significantly shorter than the I4 so the weight is moved back.  At the moment I don't remember exactly but I think the K series V6 is the same or a little lighter than the I4 the Miata got and with it moved back it could benefit the handling of the Miata.  Not that the Miata  really needed improvement at that time. .       

This has seriously got me thinking that I need to find a clapped out Miata and do the swap.  I would have to do some research on exactly what iteration of the Miata to get.  This may supersize some people out there but I really don't know much about Miata's.  Never owned one.  But I am sure people here can steer me in the right direction or at least give me the pros and cons of the various iterations of the Miata.  I wonder if it all in it could be done for challenge money.  

In reply to dean1484 :

So what you really need is a bellhousing conversion.  The duratec v6 swap has been done, and it even has a RWD application to start with.  The K series seems like it would need an adaptor made specifically for it, just like the Honda v6 conversion has

While it may be your opinion that a V6 should have been in there all the time, I've seen no records that indicated Mazda had ever planned anything other than an I4- which at the time was a BP series motor.  And when the Miata first came out in '89, the Mustang came with an I4 or a V8- for sure the 1.6l Miata was a quicker car than the lame 2.3 Mustang was at the time.  When the 1.8 Miata was introduced in 1994, that happened the be the exact same year that the 3.8l was installed into the SN95 Mustang.  And I'm pretty darned confident that there were many more Miata's racing vs. the v6 Mustang, in spite of the overwhelming sales lead the Mustang had.

Which is to say that I don't think Ford really cared about the Miata at all.  

Also, the Miata pre-dates the K series engine by 2 years.  So while the Miata was being developed, the K series was too far behind it for it to be significantly considered for the vehicle.

One interesting side note, I do recall back in 1994 that there was a project where a 3.0l Duratec V6 was supposed to be installed into an late RX7.  In theory, it was supposed to be a Lincoln, which is exactly what the V6 Miata was also supposed to be 10 years later.  Having driven that v6 Miata, I totally support your desire to make one.  Great car to drive.  Made me very much consider putting a GVT6 engine into a Spider for the challenge.

Can KL cams be dropped straight into the KJ to convert to Otto from Miller?  Seems odd that Mazda would have done engineering work to make that not possible.

pres589 (djronnebaum) said:

Can KL cams be dropped straight into the KJ to convert to Otto from Miller?  Seems odd that Mazda would have done engineering work to make that not possible.

I think it can be done BUT you have to re index them due to the change in the intake valve location.  I really don't know for sure.  I do know that the Heads are not interchange due to the Pistons in the Kj not having the reliefs for the intake valves.  It is a real catch 22 because the improved intake configuration of the KJ and the semi flat top pistons make it really a fantastic motor BUT it is down about a 1/4 of a liter as compared to the KL so that added displacement may overcome any performance gains the head design on the KJ.  The only thing that a converted KJ may have an advantage in is fuel millage due to the reduced size and greater efficiency so it could be an equal to the KL performance wise but get slightly better economy.   I really don't know the answers to all this.  It is part of what fascinates me about these. 

Just put a 5.0 in it and call it done.

In reply to dean1484 :

 That engine yells ahead of itself to warn others “if you get in my way I will beat you to death“

_ said:

In reply to dean1484 :

 That engine yells ahead of itself to warn others “if you get in my way I will beat you to death“