The Mazda MX-5 Miata ND (2016–present) is already celebrated for its perfect balance, razor-sharp steering, and 2,300-pound curb weight. But with just 155 horsepower from its 2.0-liter SkyActiv-G four-cylinder, many owners quickly crave more grunt. The good news is that the ND’s engine responds well to targeted modifications. By combining the right parts, you can realistically achieve 40+ additional horsepower at the wheels, transforming your Miata from a charming roadster into a genuine back-road rocket. This guide walks through the five most effective power upgrades for the ND Miata, with a focus on real-world gains, installation complexity, and supporting modifications you’ll need along the way.

1. Cold Air Intake – A Simple First Step

Adding a cold air intake is the easiest way to improve engine breathing and shave a few tenths off your 0–60 time. The factory airbox is decent, but it prioritizes noise suppression over flow. An aftermarket intake pulls cooler, denser air from outside the engine bay, increasing combustion efficiency. Gains are modest—usually 5–8 horsepower on a normally aspirated ND—but the improved throttle response and intake growl make the car feel livelier from every stoplight.

What to look for: Choose an intake with a sealed airbox or heatshield to avoid sucking in hot engine air. Popular options include the Cobalt Cold Air Intake and the K&N 63 Series. These retain the factory MAF sensor location for easy installation and require no tuning, though pairing with a later ECU tune will unlock the full potential.

  • Installation time: 30–60 minutes, basic hand tools
  • Average power gain: 5–8 hp
  • Improves induction sound dramatically

For more data on intake dyno results, check out the Flyin’ Miata intake page, which shows documented gains on their in-house test car.

2. High-Performance Exhaust System – Free the Flow

An ND Miata’s exhaust system is a bottleneck from header to tailpipe. Replacing the restrictive factory components with a true dual-wall header, high-flow midpipe, and a less-muffled cat-back system can unlock 10–15 horsepower. The header is the biggest gainer: the factory cast manifold kills flow above 5,000 RPM. A 4-1 or 4-2-1 primary tube header helps the engine exhale freely, especially when combined with a high-flow catalytic converter or a full catless midpipe (check local emissions laws).

Recommended setup: Start with a quality stainless steel header from Goodwin Racing (RoadsterSport or Goodwin header). Pair with a non-resonated midpipe and a RoadsterSport SuperStreet muffler for a crisp, aggressive note that’s still tolerable for daily driving. Expect a peak gain of 12–15 horsepower across the mid- to high-RPM range.

  • Header installation: 3–5 hours, moderate difficulty (requires jack/stands)
  • Cat-back alone: 1–2 hp gain; full system needed for real results
  • Sound improves, but can become loud; consider sound deadening if commuting

Many enthusiasts report that a full exhaust paired with a tune yields the best balance of power and drivability. The exhaust also reduces weight by about 8–10 pounds compared to stock.

3. ECU Tune – The Brain Behind the Power

All the hardware in the world won’t help if the engine computer isn’t programmed to use it. The ND’s SkyActiv-G engine runs lean from the factory for fuel economy, limiting power. A quality ECU tune re-maps fuel tables, ignition timing, and cam phasing (VVT) to safely extract the engine’s potential. With a cold air intake and exhaust already installed, an off-the-shelf tune can add 10–15 horsepower. A custom dyno tune can push even more.

Top tuners for the ND: Fab9 Tuning and MotoMiata both offer ECU flashing via the CanConnector tool (no need to ship your ECU). You can also purchase the OpenFlash Tablet from Vishnu Tuning, which comes preloaded with stage 1 and stage 2 maps. The process is straightforward: plug into the OBD-II port, flash the new file, and drive. Fab9 reports 30+ horsepower gains on a car with header, intake, and exhaust.

  • No hardware needed beyond a flash tool
  • Can smooth out the throttle mapping and remove the rev limiter (to 7,500 RPM)
  • Supports ethanol (E85) tuning for higher octane and power

See Fab9’s ND tuning information at Fab9 Tuning – ND Miata. Tuning is the single most cost-effective mod for the ND.

4. Forced Induction – Turbo or Supercharger

If your goal is a guaranteed 40+ horsepower increase in one bolt-on, forced induction is the answer. A turbocharger or supercharged system can safely increase boost to 6–10 PSI on a stock engine, yielding 180–220 wheel horsepower. The ND’s compression ratio is 13:1, which limits maximum boost without internals, but a well-engineered kit with a proper intercooler and fuel system upgrade (higher flow injectors and a Walbro 255 fuel pump) can produce reliable power.

Turbocharger kits: Flyin’ Miata’s Stage 1 turbo kit and the BBR GTi turbo are the two most proven solutions. BBR’s kit from the UK uses a Garrett GT2554R turbo and delivers around 170–190 wheel horsepower with safe tuning. Flyin’ Miata’s kit (based on a Garrett GT2260S) makes similar figures and includes a fabricated manifold, intercooler, and full re-tune. Expect 55–70 horsepower gains at the wheels – far exceeding the 40+ target.

Supercharger kits: For instant throttle response with no spool delay, consider a Roots-type supercharger from Edelbrock (sold through Flyin’ Miata) or a centrifugal unit from Kraftwerks. The Edelbrock kit is CARB-legal (EO D-670-26) and produces about 170–180 wheel horsepower. Both options require supporting mods: a stronger clutch (the stock ND clutch can handle about 200 ft-lb of torque, but slipping becomes an issue at higher boost) and a radiator upgrade.

  • Installation: 8–12 hours for a weekend mechanic
  • Cost: $3,000–$6,000 for a complete kit
  • Must upgrade: clutch, fuel pump, and sometimes the radiator

For a comprehensive look at the ND turbo experience, visit Flyin’ Miata ND Turbo Kit page. This is the definitive route to 200 wheel horsepower without building the engine.

5. Performance Camshafts – Advance the Breathing

Camshafts are the final piece of the puzzle for normally aspirated power. The ND’s SkyActiv engine uses variable valve timing (Dual S-VT) on both intake and exhaust cams, so swapping cams requires careful alignment and a fresh ECU tune to take advantage of the new lobe profiles. Increased lift and duration allow the engine to ingest more air and expel exhaust more efficiently, especially in the 5,000–7,500 RPM range.

Available cam options: Brian Crower (BC) offers a stage 1 cam set (256° intake / 264° exhaust) that adds 10–15 horsepower when combined with a header, intake, and tune. For more aggressive builds, stage 2 cams (264°/272°) can push that to 20+ horsepower, but you may need stronger valve springs. Remember that cams shift the powerband upward; you lose some low-end torque for top-end peak.

Cam installation is complex – it requires setting cam timing with the crankshaft locked, removing the valve cover and timing chain, and refitting the VVT actuators. Expect a shop to charge 6–10 hours of labor. Many owners skip cams for forced induction because the boost provides far more gain for less effort. However, for those who want a naturally aspirated, high-revving screamer with 170–180 wheel horsepower, cams are essential.

  • Gain: 10–20 horsepower depending on supporting mods
  • Installation: professional recommended – 6–8 hours
  • Must pair with ECU tune and header + exhaust

Read more about BC’s ND cams at Brian Crower – Mazda SkyActiv Camshafts.

Supporting Modifications – Don’t Skip the Foundation

Achieving 40+ horsepower on an ND Miata isn’t just about bolting on the big parts. The stock fuel system, cooling, and drivetrain are adequate for the 155-hp baseline, but pushing past 170 wheel horsepower requires careful attention to a few supporting systems:

  • Fuel pump: The stock fuel pump can handle about 190 whp. A Walbro 255 or similar drop-in upgrade ensures consistent fuel pressure under boost.
  • Clutch: The stock clutch begins to slip around 200 ft-lb of torque. An upgraded disc and pressure plate (e.g., ACT or Exedy) will hold 250+ ft-lb and still be street-friendly.
  • Cooling: A larger aluminum radiator is recommended for track use or hot climates. The ND’s cooling system is marginal at high sustained RPM. Mishimoto and Koyo both offer direct-fit radiators.
  • Tire and brake: With 40+ extra horsepower, you’ll overpower the stock tires (especially summer tires). A set of 200TW tires (like Michelin Pilot Sport 4S) and upgraded brake pads (Carbotech XP10 or similar) will keep you safe and fast.

Conclusion – Stacking the Gains for 40+ Horsepower

The ND Miata is a fantastic platform for building a quick, reliable, and fun sports car. To break the 40-horsepower threshold, the most effective path is a combination of the upgrades above. A typical build sequence: cold air intake + full exhaust + ECU tune = 25–30 wheel horsepower. Adding a header instead of just a cat-back pushes that to 35–40. For those who want more, a turbo or supercharger kit provides 60–70 horsepower in one weekend.

Camshafts are best reserved for naturally aspirated purists who want every last drop from the engine.

Recommended order of mods:

  1. Cold air intake (5 hp)
  2. Full exhaust including header (10–12 hp)
  3. ECU tune (10–15 hp from the combination)
  4. Turbo or supercharger (50–70 hp step)
  5. Optional: camshafts if staying NA (10–20 hp)

When all five power upgrades are combined (intake, exhaust, tune, forced induction, cams), you can easily see 150+ wheel horsepower over stock – though that depth of build requires stronger internals and a dedicated tuner. For most street-driven ND Miatas, a solid Stage 2 blend (intake, header, tune, and a mid-pipe) delivers that satisfying 40+ horsepower gain with excellent drivability and reliability.

Before you start, confirm local emissions regulations and warranty implications. For further reading and community experiences, check out the Miata.net Forum – a treasure trove of ND build logs and dyno charts.

With careful planning and quality parts, your ND Miata can go from a 155-hp budget roadster to a 200-hp corner-carving machine. That’s enough to surprise much heavier cars on both the straights and the twisties. Start with the intake and tune, and the bug will take it from there.