When building a Mazda MX-5 turbo, there are some essential parts that you’ll need to pull your build together. Some of them are obvious, such as a turbocharger, a turbo manifold and downpipe. Other parts are often overlooked, but they can add some serious firepower to your turbo build.
We have created this parts list as the ultimate resource for building your Mazda MX-5 turbo. If it’s on this list then you should probably look at adding it to your build. However, we have broken it down into stages because there are some parts you can add at a later date to ensure your MX-5 is a track day endurance weapon.
Let’s kick it off with the turbo build basics, as there are some things you’ve absolutely got to have. These are the parts you need to build an ultra-reliable Mazda MX-5 turbo. Follow this to letter and you will have a Mazda MX-5 turbo that can take all you might throw at it, without burning a hole in a piston.
The turbocharger is the heart of your turbo build. With modern turbos utilising ball bearings instead of journal bearings, turbo-lag is minimal on both 1.6 and 1.8 MX-5s, even when making more power than the standard rods can take. However, boost threshold is determined by the size of the exhaust housing. A 1.8 pumps more air through the exhaust than a 1.6 at the same RPM, so the RPM at which the turbo begins to spool will be lower on a 1.8.
The Garrett 2554R turbocharger is ideal for builds that aim for the lowest boost threshold possible and virtually zero lag, yet able to make the most of that MX-5s torque-limited rods. Perfectly suited to Autosolos, sprints and other track work that demands immediate, controllable throttle response.
The Garrett 2560R turbocharger is suited to builds that wish to wring out every last drop of performance from the standard engine, yet leave some headroom if forged rods are considered a possible upgrade in the future. Ideal for sprints, time attack and faster track work that asks for extra power.
BorgWarner EFR 6258
The BorgWarner EFR 6258 turbocharger is perfect for builds where transmission-destroying power is the main goal. Forged rods are an essential, but the outright performance on the road leaves only the fastest exotics out of reach. Ideal for the quickest tracks and supercar hunting.
2. Turbo Manifold and Downpipe
The exhaust gas needs to be routed through turbo manifold, into the turbo and out of the downpipe as efficiently as possible. The turbocharger itself is a big restriction, so ensuring flow is as smooth as possible before and after the turbo helps to reduce back pressure. With less back pressure, detonation is reduced meaning power can be increased.
Kraken Turbo Manifold and Downpipe Kit
The Kraken turbo manifold is cast from corrosion and thermal expansion resistant iron alloy. Lighter than cast stainless steel, it has many properties that make it ideal for turbo manifolds. Whilst it looks like a log, each runner is completely separate until it reaches the collector at the turbo, meaning it will support over 300bhp. Includes manifold, downpipe, studs and an optional fitting kit.
DaveFab Turbo Manifold
The DaveFab turbo manifold is a tubular manifold fabricated from stainless steel. Beautifully tig welded, each runner is as long as possible, helping the exhaust gasses to stabilise before entering the turbocharger. The route to the turbocharger is smooth and of a large diameter, meaning gasses are able to flow freely, reducing boost threshold and increasing the knock limit of the engine.
The ECU is the brain of your engine. As the standard ECU cannot be programmed, an aftermarket standalone ECU is required to control the timing and flow of fuel. Packing additional features such as knock detection and coolant based RPM limiters, they also can detect adverse operating conditions and pull timing to protect your engine.
Motorsport Electronics ME221
The ME221 is a fully featured Plug and Play ECU developed in the UK. Packing all the race inspired features you would need for the street—such as launch control, boost by gear, closed loop fuelling and more—it is the preferred ECU for professional tuners. Plus, it comes with its industry leading tuning software in the price. If you have any concerns or need help with your setup their team are available over the phone to provide fast, professional support.
MS Labs Megasquirt MS3 Basic
The MSLabs MS3 Basic offers a host of additional I/O for extra engine protection, providing all the features you would expect of a modern ECU. With clever traction control options, you’ll be able to achieve your best times at sprints, time attack, and on the track. You’ll be able to configure all the options and build your perfect map with the knowledge of the community via the forums. The tuning software is incredibly powerful but does have an additional cost.
4. Wideband Controller
A wideband controller replaces the narrowband lambda sensor that your Mazda MX-5 came with. Reading the ratio of air to fuel, it tells the ECU how rich or lean the mixture is. The ECU can use this information to make on-the-fly adjustments to your mixture and perform long-term trims, improving the drivability of your car over time. Used in conjunction with a gauge, you can monitor your mixtures on the way to the dyno when you first turbocharge your MX-5. This way you can ensure that you do not accidentally run lean, as the amount of fuel the wideband can add or remove is relatively small.
Innovate LC-2 Wideband Controller
The Innovate LC-2 is a professional digital wideband controller that comes bundled with a Bosch LSU 4.9 O2 sensor and a gauge. The ability to calibrate the sensor ensures that it remains accurate throughout its lifespan, ensuring the AFRs the ECU bases its calculations on are correct.
AEM X-Series Wideband Controller
The AEM X-Series is the latest controller to the market. Tested to be the fastest responding wideband on the market, AEM have also added the ability to calibrate the sensor so that it remains accurate as it ages. The ultra slim gauge is easy to install and the integrated controller makes free-air calibration easy.
The amount of fuel able to be delivered to the engine is determined by the size of your injectors. Upgraded injectors not only provide a greater quantity of fuel, but they feature better spray patterns. By atomising the fuel effectively, it burns more completely, producing more power and giving better fuel economy.
OEM Bosch EV14 640cc Injectors
These OEM injectors are used in one of the leading car manufacturer’s flagship sports cars. Delivering a stout 640cc of fuel per minute, they can flow enough fuel to support over 300bhp and still idle like stock injectors. Supplied with PnP adaptors, they are easy to fit and cost effective.
DeatschWerks 1000cc Flow Matched Injectors
The DeatschWerks 1000cc injectors are direct-fit into your Mazda MX-5, requiring no adaptors to install. Every set is flow matched, ensuring each cylinder receives the same amount of fuel, preventing lean conditions and detonation in your nice new built engine. Delivering a whopping 1000cc of fuel per minute, they flow enough fuel to support 500bhp.
The clutch transmits the power from the engine through the gearbox to the rear wheels. When the power of the engine exceeds what the clutch can hold, it begins to slip. Upgrading the clutch to one that has a higher power capacity will ensure the power gets down to the ground, even under the harshest of operating conditions.
Competition Clutch Stage 3
The Competition Clutch Stage 3 is recommended in power applications up to 300bhp. Featuring a segmented ceramic friction surface and sprung hub, it retains the drivability of the standard clutch yet can stand up to prolonged punishment on the track.
Competition Clutch Stage 4
The Competition Clutch Stage 4 is recommended for Mazda MX-5s making over 300bhp. Featuring a 6 puck ceramic friction surface, it will take everything that can be thrown at it. The sprung hub ensures that despite it’s grabby nature, it is still manageable on the road.
As air is sucked through the turbocharger and compressed, it can reach in excess of 150°C. High intake temperatures reduce the density of air for the same boost pressure, resulting in less oxygen to burn and therefore making less power. An intercooler cools the compressed air by passing ambient air over the core as the vehicle moves. The heat is exchanged from the large surface area of the intercooler fins to the air passing over them, reducing the temperature of the air inside the core. Higher quality intercoolers have a greater surface area, meaning they reduce the air temperature more.
Boost Products Intercooler
The Boost Products Intercoolers feature an aerodynamic effective fin and tube design, which helps keep both the intake charge temperatures and radiator temperatures low.
Forge Motorsport Intercooler
The Forge Universal Intercooler uses the best quality bar and plate cores to ensure your intake temperatures are kept as low as possible. Each is hand fabricated and rigorously tested, to guarantee great flow characteristics and maximum thermal efficiency.
8. Intake Air Temperature Sensor
The intake temperature sensor tells the ECU what temperature the air is that is entering the engine. The ECU can then calculate the density of the air that is entering the engine and adjust fuel and spark accordingly.
Intake Air Temperature Sensor
The open element design of this intake air temperature sensor allows it to detect changes in temperature quickly. The sensor body does not require grounding, meaning it is simple to install.
9. Spark Plugs
Spark plugs come in different heat ranges, which affects the spark plug’s ability to draw heat out of the combustion chamber. A colder plug transfers more heat to the cylinder head, keeping the tip cooler at maximum power and preventing detonation.
NGK BKR7E spark plugs
The NGK BKR7E spark plugs are cooler than the OEM spark plugs. This means you can be sure that your turbo Mazda MX-5 will not detonate in demanding operating conditions, nor will the plugs foul up during normal road use.
HKS Super Fire Racing spark plugs
These HKS Super Fire Racing spark plugs are the same heat range as NGK 7s. Featuring an iridium alloy centre tip for better ignition and a host of durability enhancements, the HKS Super Fire Racing spark plugs deliver high performance for premium turbo builds.
As MX-5s age, the plastic top radiator tank slowly turns from black to green. If it doesn’t blow a hole it can separate from the core, with both events leaving your coolant all over on the floor. Swapping the standard radiator for an alloy replacement yields better cooling capacity not only due to a high-efficiency core, but also due to the additional volume of water in the system.
Mishimoto Performance Radiator
The Mishimoto Performance Radiator features a high-quality 2” thick two-row core, increasing cooling capacity and efficiency significantly. Supplied with a 19psi high-pressure radiator cap, coolant is kept in the system instead of escaping into the expansion tank during demanding track work.
11. Boost Controller
Fitting a turbo probably means you will want to run greater boost pressure than the wastegate actuator will allow. Boost controllers bleed pressure off to atmosphere that would usually be opening the wastegate, increasing the amount of boost generated by the turbocharger.
Forge Manual Boost Controller
The Forge Manual Boost Controller is adjusted using a dial to adjust the amount of pressure bled off before the wastegate opens. By bleeding 5psi off a 7psi wastegate, the turbo will reach 13psi of boost before the wastegate opens.
MAC Boost Control Solenoid
The MAC Boost Control Solenoid gives complete control over boost pressure. Utilising inputs such as throttle position, gear and RPM, boost can be finely tuned for ultimate drivability and performance. Plus, boost spikes can be completely eliminated, ensuring the boost pressure you ask the ECU for is the boost pressure you get.
Optional Turbocharging Extras
To build the gnarliest track-ready turbo Mazda MX-5 there are a few more parts we’d recommend to adding to your build list. Designed to eek every last bit of performance out of your setup, these parts will take your car from B-road blaster to track day thrasher.
12. Coolant Reroute
When Mazda took the B6 from the front wheel drive 323 and placed it in the rear wheel drive MX-5, packaging for the cooling system proved challenging. To simplify packaging, Mazda moved the thermostat from the rear of the engine to the front. However, this caused poor circulation at the rear of the engine, potentially resulting in detonation during extreme operation conditions.
SkidNation Coolant Reroute
The SkidNation Coolant Reroute improves circulation throughout the engine by moving the thermostat back to the rear. Coolant is able to flow from the front, through the rear of the engine and into the radiator. All cylinders are cooled equally, allowing you to stay out on track longer.
13. Lightweight Flywheel
A lightweight flywheel reduces the inertia of the engine, allowing revs to fall faster during upshifts and rise faster during downshifts. This free-revving nature makes rev-matching a joy and grabbing gears super quick.
Competition Clutch Ultralight Flywheel
The Competition Clutch Ultralight Flywheel shaves 40% off the standard 1.8 flywheel, reducing it to just 4.98 Kgs. Forged from 4140 steel, they are extremely durable and suitable for forced induction and track use.
14. Blow Off Valve
A blow off valve vents excess pressurised air to atmosphere when the throttle closes. By releasing air through the blow off valve it prevents air reversing through the turbo. Strain is reduced on components such as throttle shafts, compressor wheels and turbo bearings, ensuring your engine lasts as long as possible.
Forge Motorsport Twin Piston Blow Off Valve
The Forge Motorsport Twin Piston Blow Off Valve uses two pistons to prevent unfiltered air leaking into the intake. With different strength springs available, the blow off valve can be tuned to work at different boost pressure so that it does not open prematurely under high load.
15. Oil Cooler
An oil cooler is absolutely essential for track use. We have regularly seen oil temperatures around 130°C on track cars, at which point most oils are beyond their recommended operating temperatures. Fitting an oil cooler drops temperatures back down to around 100°C, where it can properly lubricate the engine.
Thermostatic Oil Cooler Kit
The Thermostatic Oil Cooler Kit allows oil to flow to the cooler once it reaches 80°C. By ensuring oil comes up to temperature, contaminants are boiled off on MX-5s that see both street and track use.
Now you’ve got a comprehensive list of everything you need to build a turbo MX-5, you can check out other parts in our shop to help you go fast in the corners too.