Being one of the most popular vehicles to modify world-wide, there is a large choice of performance parts for the Miata. Which modification will give you the best performance upgrade for your MX-5? A supercharger, turbocharger or even a V8 swap? But if you have just purchased your first Miata or you are looking to start your upgrade project, there are more affordable aftermarket products that are easy to install and widely available.
Here is a list of the Top 10 performance mods for your roadster
The air intake will increase air flow, allowing the Miata to breathe more freely, adding torque and horsepower, and producing an increase in acceleration. The majority of these systems produce a 5-6 HP gain. Power gains typically begin in mid-range of the power band and increase steadily across the power curve. Throttle response is much improved after the installation of an induction, the Miata engine seems to respond quicker to throttle inputs with the lower restriction system and larger diameter inlet tube.
Most of Miata owners like the intake "roar" under full throttle acceleration, but some may feel it is too loud. Under steady cruising speeds the cold air intake sound moderates and simply blends in with the usual Miata road noise.
Several brands make Air Intakes for the Miata as for example, Racing Beat, K&N, Jackson Racing or IL Motorsport.
Letting air flow out is just as important as getting the air in, so getting a new muffler, a midpipe, new tips, or an entirely new exhaust system can provide mild performance increases. Factory exhaust systems can also be heavy, meaning that replacing it with a lighter aftermarket system will give the car more power while cutting weight, leading to a better power-to-weight ratio.
Racing Beat, a renowned brand for their well built aftermarket Mazda exhausts, mention that "header design will vary greatly from manufacturer-to-manufacturer, but most produce similar power gains. Typically power gains are realized beginning in the 3000 RPM range, extending up the 6500-7000 limit".
There are several brand for Miata performance exhaust systems as Borla, Enthuza, Racing Beat, RoadsterSport and Integral Kobe.
Coilovers allow maximum flexibility in adjusting the height of the car, while also allowing for a more controlled ride. V-MAXX offers an extensive range of premium coilover kits for the NA, NB and NC MX-5, with sporty but comfortable spring and damping characteristics for both daily and sporty use.
One of the easiest and most economical ways to noticeable improve the handling of your Miata, without increasing ride harshness, is by upgrading your sway bar set. A new sway bar set will reduce the body roll of a Miata MX-5 while helping to increase traction and improving weight transfer during manoeuvring. Reducing the body roll of your Miata allows for increased traction and improved weight transfer. Sway bars are usually designed as a front and rear matched-set by the manufacturer for each specific application.
(Photo courtesy of Andrew Foy, Downshiftaus)
Being a roadster, the performance of the Miata is more centred around manoeuvrability, and there’s no better place to start then with the wheels and tires. By changing the size of the car’s wheels, drivers can increase the contact patch with the road, making it easier to transfer power and change direction.
When shopping for new Miata wheels and tires there are a couple critical issues to consider weight, offset and size, better to stick to either 15' or 16' diameter as any larger than this will spoil the excellent handling of the MX5. Most enthusiasts prefer Enkei RPF1.
When making a tire selection, consider smaller companies such as Toyo, Uniroyal, Falken or Kumho, they produce some outstanding performance tires at very competitive prices. Select a tire that is suitable for use for your local road conditions and weather conditions. Higher performing tires tend to have stiffer side walls, which will produce a harsher ride quality in areas with poor road conditions.
With the concentration on handling, new brakes will allow the car to carry speed further into the turn, while cutting down on braking distance. Brake pads, brake calipers, and brake discs can all be replaced individually, or the entire brake system can be replaced all at once with a new brake kit.
V-MAXX makes Big Brake Kit ready to fit on the front axle of the NA or NB/NBFL MX-5, with 4-piston forged aluminium calipers, high performance brake pads, grooved 2-piece high carbon steel brake discs / ultra light floating aluminum hubs.
Installing a big brake kit will depend on the size of the wheel, the distance between the caliper and wheel, also as the ET value which you can also reach by using spacers.
While a new, lighter flywheel won’t provide a pure horsepower increase, what it will do is reduce resistance during acceleration, letting RPMs rise and fall faster. This allows the driver to move through the gears faster, cutting acceleration time.
The lighter part will also reduce the overall weight of the vehicle slightly. Performance flywheels are typically lighter versions of the stock components, significantly reducing the moment of inertia that is required to rotate the the flywheel, allowing the MX-5 engine to more efficiently utilize the available power by improving its revving capabilities, you've simply regained power that was being consumed by the heavier flywheel.
Good Win Racing offer quite a large choice of flywheels for all Miata models.
To skip all of the minor performance steps, look no further than forced Air induction using turbocharger technology. While these systems can be quite expensive, and owners will likely need a trained mechanic to install them, they can provide immediate horsepower boosts, even more than double the base horsepower.
Both 1.6 and 1.8 engines are suitable for Turbo build, even though it's said the 1.6 is more robust and able to handle forced induction easier, as it came with a turbo from the factory for other Mazda models (323).
A turbocharger should never be the sole upgrade, though, as that much power will change the behaviour of the car - new wheels, tires, and other handling upgrades will be necessary.
While a Turbo needs to be spooled by exhaust gases before it compresses the air, to make more power at peak, a Supercharger is run off the serpentine belt, and will constantly draw on the engine's power to spin the scrolls, regardless of boost pressure or throttle position, which means no need to wait for peak power (turbo lag)
But also consider that a supercharger will hurt fuel economy more, as with a turbo, while you are not in boost, your fuel economy will remain basically the same.
(Photo Courtesy by Peter Lysakowski, MX-5 Unleashed)
Talking about Miata engine swap, first comes to mind LS V8 swap, as per Flyin' Miata: "The math is simple. Little car plus big engine = high performance. The trick is putting the big engine in without spoiling the little car. The engine ranges in size from 5.3 to 6.3 liters and makes a minimum of 300 hp and 300 ft-lbs with a wide range of upgrades available."
The Rotary 13b and 20b swaps are worthy but difficult, 13b's have been done already, and one of the first swaps goes back to 1992 as per this archive article from Road & Track.
Recently we are seeing more engine swaps as the Honda K24, K-Miata mentions: "As a K24 Integra track car owner, as well as a Miata owner, this swap just needed to happen. Honda reliability, and a 2000 lb. RWD chassis with legendary handling is going to make the perfect track car, or even daily driver."
(Photo: Joe Coville)
If you stay NA (normally aspirated), you have to skim your cylinder head.
This "uber simple" mod will bump the efficiency of your miata engine at all revs.
More torque (which the 1.6L lacks a lot!) and thus more power.
Guys, there is around 15 hp to grab here! Bump your compression ratio by one point with just a 1mm head skim (40 thou or 0.040 inch) will raise your compression ratio from 9.4 to 10.3 to 1, there is absolutely no drawbacks, just use 91 octane fuel or upper.
Thanks to this mode my car makes 161 N.m of torque and 132 hp, it made 135 N.m and 113 hp stock.
There's no other mod which give you so much in such a wide rev band and for less than 200$.(gasket and head bolts included)
Nowyou can left traffic behind without downshift, just press the right pedal, or just cruise confortably in the lower rev range enjoying the quietness and the freshly added torque.
And dont forget all your futur mods will profit from this basic architectural engine change ;)