monty11ez

Lol I just noticed that it was on the first page so I didn't think it was that out of date. But it is still good information for those looking.

Jason_Saini

It's very clear that most on here don't think the MZR/DISI swap is a good idea on the RX8, and while there are even more wild and crazy swaps going on, I wanted to at least post a little more info on this swap that's not on here (not the least of which because we're about to try one.)

Let's clear up first some of what is 'easy' about this swap, then we'll tackle what's hard...

Easy:
- By using an MX-5 Subframe and engine mounts, it bolts right in, notwithstanding interference with the firewall which I'll address in a moment
- If you use an MX-5 6-speed trans with the tail housing from an '09+ RX-8, the trans will bolt right to the engine, and and mate right to the RX-8's PPF.

Unfortunately, that's about the easiest part - although all that physical mounting and trans adaptation is often the trickiest part of any swap. In this case, it can be done with mostly factory parts. In fact, I would just use the MX-5 Steering rack and PS pump, or adapt an MS3's electric pump to the MX-5 Rack.

Now onto the hard parts:
- Intake and exhaust are backwards. There are options, but they aren't that great. You could use an MX-5 intake manifold, but it's pretty flow limited. There is a custom fabbed manifold that can be built facing the right direction, but it's not cheap. As for the exhaust, you could make a custom manifold or adapt one of the aftermarket ones out there.
- Need to fab an entire Front-Mount Intercooler and piping solution (not that hard)
- Wiring/ECU/Cluster from donor car would need to be adapted
- ABS would best be handled by using a non-DSC ABS pump from Japan
- Completely custom exhaust downpipe would need to be fabricated
- Firewall would need to be clearanced for the high pressure fuel pump on the back of the head

All that being said, if some solutions are found, the swap might actually end up being one of the easiest in the RX8, and with power potential from a mild 290-300whp and up to a wilder 400whp, it would be a fun car for sure.

Sure, an LS swap is easier - but some people don't like them. In fact, if we move forward with this project, it will be someone who put an LSX in and is pulling it out to do this swap instead.

Anyway, I just wanted to share since it seems most threads on the subject are low on facts and high on troll bait/bash.

TeamRX8

iTrader: (25)

Most people don't agree with those other crazy swaps either. There is both misinformation and information out there. This thread started quite a few years ago and nothing stands still technology wise. If you're paying any attention at all to the results of combining a 13B engine with the latest BorgWarner EFR turbos then the only purpose an MZR swap serves is to just be different damn the common sense.

It makes as much sense as putting a Renesis engine in a Miata, no wait ....

ejv8s10

600 hp Renesis?
I fixed that for you.
My FD convinced me that Wankels don't live long when thrashed.

Osator90

SWAP with MZR series engines (https://en.wikipedia.org/wiki/Mazda_L_engine)

NotAPreppie

So, what about the 2.3L Ecoboost out of the Mustang? IIRC, it mates up to a MX-5 gearbox and should have the same mounting configuration as the rest of the Duratec/MZR engines. Additionally, it's already got intake and exhaust setup for a longitudinal arrangement. I think I also read somewhere that this is the same engine going into the Focus RS, so 350HP is achievable and between that and the Mustang, there should be a fair bit of aftermarket support.

Granted, the engines are going to be a little pricey until people start wrecking Ecoboost Mustangs but at least the parts exist.

yomomspimp06

mazdaspeed 2.3l is basically the same as the ecoboost. can be had for much cheaper

Osator90

2.3 DISI Turbo engine is quite similar to the 2.0 MZR engine that I used in my Rx-8. But there are slight differences. The biggest problem is that on the back of 2.3 engine is an extra accessory. Which will be hard to fit. There is very little space between the back of the engine and bodywork. To fit 2.0 MZR engine I had cut out 3 holes. But nothing is impossible

NotAPreppie

All things are possible with a reciprocating saw and a sledge hammer.

Brady Black

Awesome build! It seems like most of the miata guys these days are using the 2.5 MZR out of the second gen mazda6 though. Was there any reason that you didn't do that swap instead?

NotAPreppie

Probably availability. The 2.5 MZR may not be very common in his part of the world.

billyboy

It can be eliminated or minimized at least, there's low profile ones available in the aftermarket. Still need to mod the firewall and, probably the windscreen plenum too - if a wet sump is retained and with the engine behind the rack.

Bwek

Yes the MZR bolts in, the rx8 driveshaft fits perfect, the PPF works, NC subframe works NC steering rack works.

Just waiting on an NC oil pan, goodwinracing long tube header, moto east 1.5 cams.

Ill be using a ford fusion 2.5 duratec even though i have a Disi pictured

Probably be using a Mazda3 ecu,cluster and key to run this setup

Tunkka

Ford Focus ZX3 SVT is also good lightweight engine with super flowed head and forged pistons. Stock engine good for 300hp with some boost. On the market parts for RWD conversion are easily available.

Rkesh88

Has anyone thought about the Mazda L5Y0 2.5 motor? I know it is swapped into the NC seamlessly and even boosted. The motors are relatively cheap and come out of Mazda 3s and fusions.

Bwek

that is what I posted Pictures of

Osator90

How's progress ?

Bwek

Pretty good got the 2.5 in

Ewen

Hi all,

Watching this one with interest. I'm looking at swapping one of two engines into my RX-8: Jaguar S-Type AJ30 3.0 V6 (Longitudinal Ford Duratec 30 with VVC) or an LF / Duratec inline 4.

Long story short, the AJ30 is on hold while I look at the LF / Duratec engine as an alternative. I've just put an MX-5 NC front subframe in there and am looking at a weedy Mazda 6 2.0 LF engine that happens to be in my garage, just to get the thing mobile again while building something based on a 2.3 / 2.5.

Where I live, heaters are quite important. I understand the required bulkhead mods necessitate mods to the heater box / system. Has anyone done this successfully? Will you guys be posting details on here, or do you tend just to run without heaters?

Couple of other questions if I could please:
Am I right in thinking that the Mazda-LF-flavor bellhousing pattern is just the same as the Ford-Duratec-flavor version? I take it the NC MX-5 6 speed hooks right up to Ford-Duratec-flavor engines as well as Mazda derived ones?
Is the 1.8 MX-5 NC engine essentially the same LF as the 2.0? I'm pretty sure it is and assume that engine mounts, sump etc from one of those will fit the 2.0 version. Is that correct?

Does the engine need to be canted over off vertical as per Bwek photos? I'd been going to just install it upright, but I guess it'll be decided by the MX-5 engine mounts? If it should be at an angle, does anyone know what the angle is to help measuring things up ahead of gathering MX-5 mounts?

Last one - does anyone know if the stock MX-5 NC exhaust manifold fits when using this stock parts / MX-5 subframe approach?

Thanks!

Bwek

1. Heater core i havent gotten to yet, chances are its gone.
2. motor sits on an angle in the Nc and will need to sit on an angle in the Rx8.
3. Above picture is with an NC Subframe and Stock NC exhaust Manifold.
4. there is no 1.8l Duratec variant so you need everything from the 2.0
5.Duratec=MZR=LF=Ecoboost=DISI they all share the bell housings and basic block configurations.
6. if you are going to do this you will need an NC parts car, i have access to a miata shop to pull everything I need.

Nobody else except for the Polish guy and me have done this so far, I Used More OEM parts that the Polish guy.

Ewen

Hey Bwek,

Thanks for this. Much appreciated.

A donor NC would make sense, not having access to a Miata shop myself!
I think I'll put things on pause and look out for a rear-ended one to use. It's going to be cheaper and easier in the end, isn't it?

Bwek

if you get one for less than 2k than it makes sense, Im about $700 in for everything, Hoping to have the car done for $4k including the cost of the car

Osator90

I need to say that it looks very very very very nice :D You placed the engine much deeper than me. This gives you a better weight distribution.



But I'm afraid that now you're gonna have a big problem with heater core :/
I placed my engine as deep as it was possible to keep heater core untouched


Because of that I had a lot different problems to solve.

For example:

- Change (extend) the gearbox mount ( I used 5 speed gearbox )


- Change the gear shifter



- And buy a custom drive shaft

But because of that I keep my heater core untouched, and it's working :D
If you got some question, feel free to ask
And inform about the progress, I'm curious :P


And this is my treasure :P

Bwek

Ill post more pics for you Osator90

My shifter is in the oem spot, Im using a 6 Speed NC transmission with an S2 Rx8 tailshaft. Im also using the OEM Driveshaft

I might do an NC miata heater Core as it would be out of the way.

You should swap out that Power steering pump for just the Pulley version.

Your motor seams to sit much lower if it can fit under that strut bar.

Osator90

Yes I know :P that Power steering pump was supposed to be only temporary. I'm gonna change it on Pulley version but I can't find time :D

In my car I used factory (RX-8) subframe and I make my own (custom) engine mount



That's why my engine sit much lower. I was able to adjust it

And I keep electric power steering from RX-8


Because it was one of condition to keep DSC working.