Photography by Travis Ingram
[Editor's Note: This article originally appeared in the May 2019 issue of Grassroots Motorsports.]
The Miata could use more power. It’s something that’s been said since the dawn of time–or at least since the car’s release some 30 years ago.
We said it, too, in fact, in one of this magazine’s earliest new-car reviews. “The Miata’s powerplant was the most often criticized feature,” we reported after putting the original car through its paces. “Most of the drivers simply felt it needed to be more powerful.” That was the sole flat note in the otherwise harmonic Miata package.
Of course, the aftermarket quickly offered the car a boost. Late in 1989, we featured a Miata performance buyer guide: wheels, shocks and the like. Right there in the middle of the spread was a glimpse of things to come: the mention of a forthcoming bolt-on turbocharger kit from Corky Bell’s Cartech. The kit promised higher top speeds and zero-to-60 times in the low-7-second range.
Fast-forward to today, through four generations of Miatas, and you’ll notice a constant: an aftermarket ready and willing to supply more power. One of those companies is Flyin’ Miata, a firm birthed in 1983 by Bill and Teri Cardell as a service center for Porsches, Audis and Volkswagens.
“One day in 1989, one of our Porsche customers came by and threw us the keys to his brand-new Miata,” the company’s website explains, “and we fell in love. Within a couple of months we had turbocharged our own Miata and a new business was born.”
Today, that same business offers power upgrades for all variations of the Miata, MX-5 and Fiat Spider, with the menu including turbo, supercharger and V8 options. So, we wondered, how do the different generations of the Miata respond to a little forced feeding? Only one way to find out, so we rounded up a modified example of each generation. Our base of operations would be Grand Junction, Colorado, home of Flyin’ Miata as well as Grand Junction Motor Speedway, our test course for the day.
NA chassis code • approx. 180 wheel horsepower
Major Mods
On the Street
On the Track
Final Thoughts
NB chassis code • approx. 240 wheel horsepower
Major Mods
On the Street
On the Track
Final thoughts
NC chassis code • approx. 220 wheel horsepower
Major Mods
On the Street
On the Track
Final Thoughts
ND chassis code • approx. 205 wheel horsepower
Major Mods
On the Street
On the Track
Final thoughts
The Miata is arguably the most fun car in the world. Add forced induction, and that argument becomes an indisputable fact.
All of the cars we tested, even the rather rough-and-tumble NB, exhibited essentially flawless drivability. None of them felt like they were equipped with aftermarket components. The experience was factory throughout.
Yet each one had its own charms. The NA still delivers a truly delightful driving experience. For about $12,000 to $15,000 all in, you could have a perfect NA with all of the chassis and go-fast parts you need.
The ND, once modified, starts to pick on cars from a higher weight class. We didn’t expect much less, to be honest. It’s a great chassis that, as always, could use a little more power. If you have the scratch to handle the car payment and the mods, this is the one.
The NB that we tested had the most modifications. It was definitely the fastest, but it was also the rowdiest of the bunch. Its other shortcoming: It didn’t have the charm of the NA or the comfort and sophistication of the later cars.
The much-maligned NC was the hit of the day for us. It offers so much more comfort and sophistication than the earlier cars but without any cost premium. When you factor performance and usability against price, this generation of Miata quickly becomes a very strong contender.
How about this for a final verdict: If you’re looking to keep things pure, you can’t beat the NA. But if you can go a little more contemporary and price is a consideration, the NC quickly becomes the one to get.
Norman Garrett served as the design engineer for the original Miata, but early in 1990 he left for another OEM. Two and a half years later, he explains, he launched his own line of reasonably priced Miata superchargers:
In the product plan for the P729 project, aka the Miata, we recognized that the customers might want more power, but that putting more power in at the OE level would trash the insurance rating. At the time–1985 or so–the Honda CRX Si was getting terrible ratings from the insurance companies due to its power. Some teenagers were paying hundreds of dollars a month for insurance, and this affected sales.
So, we thought ahead for the aftermarket as a way to get to the higher power levels. One idea was to nest a supercharger in where the power steering pump was located on the left-hand side of the engine. Superchargers (Roots and Lysholms) work great on track cars because the power delivery is so linear, and the kind of power they deliver is more in line with the character of what the Miata was about–less drag racer, more road racer.
Around 1992 to ’93, I saw that only a few turbocharger kits were being offered, the best being the BBR system that was factory-warrantied in the U.K. Corky Bell had a great turbo kit here in the States, and Bill Cardell followed suit. All of these kits cost over $3000, which I thought was a shame since that was too expensive for most owners.
I remembered our idea of a supercharger option from my Mazda days, and once Eaton had established themselves as a great OE supplier, I approached them to see if they made a blower small enough for a sub-2.0-liter engine.
They did not, but said that if I guaranteed to purchase 50 units per month and paid all the tooling and engineering costs, they would make a smaller supercharger just for me. I asked for exclusive rights to the aftermarket for all Eaton supercharger applications, and we struck a deal. Sebring Superchargers was born, and I asked racer Jim Downing to be the front office. Rob Ebersol did our logo and ad work.
I designed the first kit as a drop-in product with OE quality–no drilling, etc., required for installation–and priced it at $1995. The kits ran 6.0 psi of boost, added 40 percent to the horsepower output, and only took one Saturday morning to install.
We tested and obtained approval from the California Air Resources Board, then made kits up through the NB generation.
They sold like hotcakes.
We also developed kits for the four-cylinder BMWs of the time–3 Series and Z3–plus prototyped units for 5.0-liter Mustangs and GM 5.7-liter V8s. I approached Oscar Jackson and we put together a great kit for the Civics, then Preludes and other Hondas, sold under the Jackson Racing name.
We grew quickly and got to the point after a few years that the business became too large for us to manage without hiring on a lot of people. Holley came to visit and made noises about purchasing us. In the end, Moss Motors made an overture and we sold the lot to them, and Oscar sold them the Jackson Racing name at the same time.
Just in time for me to get the town bike.
This test just confirms what I think about my 95M. Pure, analog driving fun that is bank vault reliable. I have yet to boost it, but sometime soon, I hope.
The Mazdaspeed Miata, a factory Turbo car should have been included. With a thousand different parts than a non Turbo NB they are amazing substantial cars.
Unsure which one is better in the long run, Turbo or Supercharger for the 2016+ ND?
I own 25% of those cars. 
levireyes said:Unsure which one is better in the long run, Turbo or Supercharger for the 2016+ ND?
Turbo in both the short and the long term.
Too bad the NB example with the most HP wasn't better sorted and on much better tires. Curious to see where they would have ranked it if it were equal build quality of the others.
If you do a similar test again I might be interested in driving my NB2 w/FFS MP62 coldside up to CO.
I agree whole heartedly to this assessment. My NA is pretty close to the NA here only with a bit more boost. It's really easy to love and a lot of fun. The NC is very under-rated. I would build one of those again at some point.
jonk67 said:Too bad the NB example with the most HP wasn't better sorted and on much better tires. Curious to see where they would have ranked it if it were equal build quality of the others.
195 all seasons definitely aren't up to track driving on a turbo Miata...
I would be very interested in hearing the lap times for all the cars, if they were timed.
bmw88rider said:I agree whole heartedly to this assessment. My NA is pretty close to the NA here only with a bit more boost. It's really easy to love and a lot of fun. The NC is very under-rated. I would build one of those again at some point.
Every time I'm in a NC I feel like it's a cousin to the other three. The NA, NB and ND are clearly siblings. That's not to say it's better or worse, just not quite the same DNA.
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