Mazda DISI Engine
DISI
From Ford, South Africa
The heart of every Mazda is its spirited power train – the ground breaking 2.3-litre DISI Turbo embodies the spirit of the Zoom-Zoom philosophy and takes it quantum leaps forward.
The MZR 2.3 DISI Turbo is Mazda’s latest generation engine, developed and engineered to fully embody the company’s spirited DNA and be the ultimate expression of the Zoom-Zoom experience.
DISI stands for Direct Injection Spark Ignition and the engine function hinges on exactly this description. In other words, the fuel is injected directly into the combustion chamber where the ignition is via centre-mounted spark plugs.
The 2.3 DISI Turbo engine was developed to have the best balance among light weight, fuel efficiency and power. Superior to a V6 engine that has the same level output in terms of fuel efficiency and emissions, the DISI Turbo is also lighter and smaller than the V6, decreasing weight in the front of the vehicle. The result – nimble handling that is distinctively characteristic of Mazda products.
The powerful MZR 2.3 DISI Turbo engine features in the Mazda3 MPS, Mazda CX-7 and the stylish Mazda6 MPS.
Engineered to deliver high performance at all speeds, along with low exhaust emissions and excellent fuel economy, Mazda's 2.3 DISI turbo-charged engine produces an enthusiastic 191kW at 5 500rpm and offers up a sizeable torque peak of 380Nm at just 3 000rpm in the Mazda6 MPS. The 0-100km/h sprint is achieved in just 6.6 seconds, but that doesn’t mean you’ll be breaking the bank for the fuel bill.
Key advantages of the DISI Turbo engine:
- Outstanding acceleration – the DISI engine has been specifically designed to out-perform naturally aspirated large capacity engines.
- Flat torque curve – With 90% of the engines usability available above
2 500rpm there is virtually no turbo lag.
- Low fuel consumption – the high compression ratio contributes to excellent fuel economy.
- Environmental compatibility – fast catalytic heat-up results in low emission levels.
“The DISI Turbo is more than just a high performance machine – it combines tremendous power with user-friendly driveability and unparalleled fuel efficiency. It takes modern motor engineering into the future and is on the leading edge of motoring dynamics,” explains Doreen Mashinini Marketing Manager Mazda South Africa.
“In order to achieve the overwhelming driving experience which is distinctive of Mazda, the engineers developed an engine that embodies the best of both worlds. The DISI engine boasts outstanding acceleration with high levels of controllability throughout the rev range.”
Introducing a direct injection system to the turbo engine infuses the already powerful acceleration that is characteristic of turbo performance with ample low and mid range to deliver excellent response, while also realising lower exhaust emissions. This is like combining the best of diesel output (lower speeds) and petrol engines (higher speeds). In other words the best of both worlds. All told, this next generation power unit brings a new dimension to Zoom-Zoom performance that Mazda simply could not produce with a large displacement naturally aspirated engine.
Increased low to mid-range torque – The internal cooling effect when fuel, at pressures as high as 11.5mPa is injected directly into the combustion chamber, improves the loading efficiency of the cylinders resulting in a linear increase of rotation speed of the turbocharger’s compressor blades. The turbocharger compressor starts adding substantial boost from around 2 500rpm and torque is increased by up to 10 percent at around 3 000rpm, resulting in outstanding engine response in the low to mid range.
A single turbocharger covers all speeds - The merits of the direct injection system noted above make effective boost possible from low through high speeds using a single-scroll turbocharger, which is light in weight and simple in construction. The thermal capacity of the exhaust system is thereby greatly reduced, minimising the decrease in temperature of exhaust gases to help comply with strict emission regulation.
High compression ratio contributes to improved fuel economy: The internal cooling effect within the combustion chamber improves anti-knock characteristics and improves the engine’s fuel economy without losing low-end torque, even running at a high compression ratio.
The form and materials used for the respective components are optimised to bear the added load and heat of the increased output. The cylinder block and cylinder head are made using a new implementation of the Advanced Precision Mazda Casting process, which increases their strength. In addition, cross drilling between the block liners and between the valve bridges on the cylinder head improves resistance to heat. The crankshaft and connecting rods are made of steel, the diameters of the connecting pins increased, the shape of the rods optimised, full floating pistons introduced, and made to ensure that all moving parts are stronger, more rigid and more durable.
Special effort was made in the tuning of the exhaust to optimise torque output and present an appealing exhaust tone that heightens the Zoom-Zoom driving experience. The shape and size of the inner diameter of the exhaust pipes and the internal structure of the silencer produces a throaty, sporty sound when accelerating from a standing start from a low speed, and a pleasing linear curve at high speeds. The exhaust system also adopts a tailpipe with attached diffuser that enhances the sporty appearance.
An electronic throttle and an electronically controlled turbo boost system deliver a superior balance between refined linear acceleration and lively, aggressive response with the relatively high-torque from low speeds produced by the direct injection engine.
“With the DISI Turbo engine, Mazda will dramatically enter the high performance market,” continues Mashinini. “It is the next generation in the Mazda Zoom-Zoom annals, offering formidable driving pleasure that will awaken your inner child".
“It is without doubt a quantum leap in Mazda engineering and we look forward to the prospect of the DISI engine making waves on the local market. Something special is coming,” she concluded.
