Engine Mitsubishi 3B21T

The Mitsubishi 3B21T 1.0-liter 3-cylinder turbo engine was produced from 2006 to 2014 and was installed on advanced versions of the second generation of the Smart Fortwo model in the back of the W451. The usual modification of this unit developed 84 hp, and in the version from Brabus from 98 to 102 hp.

The 3B2 family also includes engines: 3B20, 3B20T and 3B21.

The engine was installed on:

  • Smart Fortwo 2 (W451) in 2006 – 2014.


Production years 2006-2014
Displacement, cc 999
Fuel system distributed injection
Power output, hp 84 – 102
Torque output, Nm 120 – 147
Cylinder block aluminum R3
Block head aluminum 12v
Cylinder bore, mm 72
Piston stroke, mm 81.8
Compression ratio 10.0
Features DOHC
Hydraulic lifters no
Timing drive chain
Phase regulator MIVEC
Turbocharging MHI TD025M1
Recommended engine oil 5W-30
Engine oil capacity, liter 3.4
Fuel type petrol
Euro standards EURO 4/5
Fuel consumption, L/100 km (for Smart Fortwo 2012)
— city
— highway
— combined
Engine lifespan, km ~200 000
Weight, kg 69 (without attachments)

Disadvantages of the Mitsubishi 3B21T engine

  • This power unit is quite reliable for a turbo engine, but its consumption is too high;
  • The main thing is to monitor the cooling system; in case of overheating, it immediately leads the head of the block;
  • Due to hardened o-rings, grease often pours into candle wells;
  • Closer to 150,000 km, the turbine or timing chain may already require attention;
  • Since there are no hydraulic lifters, the valves need to be adjusted every 100,000 km.

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