Let's 2.5-swap an NC Miata in a single day!

In reply to z31maniac :

nope, different stroke. the ranger version is setup to be a lower revving truck power band. I'm sure Keith can speak to this much better, but they're all the Mazda "L" engine. LOTS of variations and high production #'s: https://en.wikipedia.org/wiki/Mazda_L_engine

I can't help with Ranger engines, sorry.

z31maniac said:

bluej said:

DeadSkunk said:

In reply to z31maniac :

I thought Ford used this same engine, but without the balance shafts in the later Rangers. I could have that wrong, too.

'01 up got the 2.3 version, sans balance shafts.

Did it have a different crank? Same rev limit? Hp/TQ output? etc. 

The heads of the 2.3 and the 2.0 are the same, but the Ranger has lower lift/duration cams thanks to it's drive cycle.  At least that was the story when I worked on them in 2001.

In reply to alfadriver :

So you get a super 2.3 if you put 2.0 cams in a 2.3?

z31maniac said:

I'm also curious about deleting the balance shafts. I feel like the millions and millions spent on engine development by OEMs wouldn't have added extra cost and complexity for no reason.

 

I really loved my NC, and an easy well documented swap would consider me picking up an NC and swapping it vs getting an ND.

I was told a ND is better [faster?] than even a modified NC.I wonder what it would take to make an NC faster, just FI? It  would be cheaper, at least for awhile

Hmm. It's going to come down to the test. The ND is considerably lighter and generates ridiculous amounts of lateral grip, with an engine that punches way beyond its power rating. But once you get into the higher speed ranges, power/drag becomes more important and the FI NC would start to come into its own. I don't have the lap times on hand right now for our local track, but from what I recall our supercharged NC with suspension/tires/wheels was right about the same pace as our 2016 ND was with nothing more than some 205-section tires. Take those cars to High Plains Raceway and I suspect the NC's pace down the straights would let it outrun the ND over the course of a lap.

The more important thing is the packaging and the feel. They're quite different cars to sit in and steer, so make sure you like the platform above all else. 

Matthew Kennedy said:

In reply to alfadriver :

So you get a super 2.3 if you put 2.0 cams in a 2.3?

Pretty much.  Instead of Fusion or Focus cams, I'd lean to some performance cams- I doubt they are that expensive.

In reply to Keith Tanner :

If Wiki is right, the ND and the NB weigh almost exactly the same.  Which really makes one ask about the other thread- putting a duratec/mzr into the earlier chasssis.  

There's been a lot of work done on making the MZR/Duratec a proper sports car engine in the UK. I agree that in stock form it was an adequate Miata engine - a platform that's always been about decent engines in a great chassis. The extra displacement doesn't transform the engine, just makes it more of the same.

alfadriver said:

In reply to Keith Tanner :

If Wiki is right, the ND and the NB weigh almost exactly the same.  Which really makes one ask about the other thread- putting a duratec/mzr into the earlier chasssis.  

NB weights vary quite a bit over the years. The ND is back in NA territory, really.

What's there to ask? My basic thoughts haven't changed in that regard since that thread was started in 2012. Being a Mazda-branded engine doesn't make the swap any easier. So outside the need to use it for some other reason, there are a lot of other, more compelling options out there for the same amount of effort.

Actually, the math has changed. Since that 2012 thread, the number of options on the market has exploded. There are kits for three types of V6, K-series Hondas, Ecotecs, and I'm sure I've forgotten something. No kit for an MZR. If I were cutting and welding on my own car and I wanted a revvy four, I'd be looking at S2000 or K-series engines. The Rocketeer V6 comes with a subframe that's best in class. The MZR just doesn't stand out in stock form.

I have been considering an MZR swap on one of my NAs if that project ever makes it to fruition, but the engine branding is a factor and it would not be a stock engine.

In reply to Keith Tanner :

The thing for me is that I'd like Ford on the cam cover.  So Duratec or nothing.  That's all.  If it takes more because the layout of the rollerskate, well, so be it.

That's one of those "other reasons" I mentioned. From a purely technical standpoint, it's a tough justification. But it if was all about purely technical, we'd all be driving  $20k Z06s :)

You can get a Ford-branded valve cover for your BP. That's a lot easier...

alfadriver said:

Matthew Kennedy said:

In reply to alfadriver :

So you get a super 2.3 if you put 2.0 cams in a 2.3?

Pretty much.  Instead of Fusion or Focus cams, I'd lean to some performance cams- I doubt they are that expensive.

Yeah, but stock cams are super cheap and plentiful. Thoughts on which might be best for a street car w/ the 2.5 swap?

To bring this back to the NC swap, I don't recall seeing anything about the cam timing setup. Was it the same?

So has there been any real world testing on the differences between the 2.5 head and a Miata head on the 2.5 block?

bluej said:

alfadriver said:

Matthew Kennedy said:

In reply to alfadriver :

So you get a super 2.3 if you put 2.0 cams in a 2.3?

Pretty much.  Instead of Fusion or Focus cams, I'd lean to some performance cams- I doubt they are that expensive.

Yeah, but stock cams are super cheap and plentiful. Thoughts on which might be best for a street car w/ the 2.5 swap?

To bring this back to the NC swap, I don't recall seeing anything about the cam timing setup. Was it the same?

Yeah, but I can't imagine going through the work of swapping engines, pans, cams, etc, and cheaping out a few hundred on higher performance cams. 

In reply to z31maniac :

I'm less than $400 into replacing the blown up 2.3 in my b2300 w/ a 2.5, and don't necessarily want to move the powerband up a ton. I don't see the harm in exploring if there's a stock option that would represent a good balance.

I know there are different cam position sensing setups that will drive part of this answer, too.

Great write-up

acidjzaz said:

Great write-up

That's what they do here. Welcome aboard.

Yes, great write up indeed.  I think the NC is overlooked but now that the pricing is getting cheap and NA/NB cars are starting to go up in value, people are taking a second look. They are just a spring/shock/sway bar upgrade away from really being great drivers. I put the biggest tire and wheel combination you can fit in the stock wheel wells (235/45/17), upgrade the brakes and suspension/sway bars, exhaust and it is perfect for me. Anyone that has one knows the 2.0 is really a decent performer, but the 2.5 with more torque and 30 more HP is definitely something I am considering if my engine ever goes, that is likely what I will do. I keep asking myself if another car would do everything my NC does and short of a newer ND, the answer is always not likely. The car puts a smile on my face just running down the street to the store, so to me that is the perfect car.

Has there been any power numbers associated with this swap?  So the 2.5 can get to 210?  Is that correct?  Tune and exhaust make it to that number.   

Thanks

For just a stockish swap you are more like 160-170 range with headers and exhaust with a tune. Step up to cams you are in the 190s range. 

Stock is rated at 167HP 

BMWrider88 - thanks, I corrected my statement. 

The 2.5 swap is much more about mid-range gains than peak gains. Most people appear to be seeing only a 10-15 peak hp gain over similarly modded (intake, header, exhaust, and tune) 2.0's...However there is something like 30 or 40 hp gained in the midrange.

Agreed Driven. You notice it a lot about 2500-4500 range. I've driven a few and I liked it for flat lander applications. If I was still in TX, I'd have a NC track car with the 2.5L swap and Fox suspension and just enjoy the heck out of it. 

Just read this in the magazine this morning. Fantastic article! Love all the documentation on the little details. I feel like I could do this swap this weekend, if only I had a broken NC in my driveway...