Mcc Smart Turbochargers

The Mcc Smart turbocharger is a hard worked part.  It does however seem to last well, really only the early manifolds being a problem.  The main cause of failure was cracks appearing in the manifold itself, causing fluctuations in boost pressure.  This affected performance and economy.  The manifold was re designed around 2002 and the problem seems to have almost gone now.  They are robust units experiencing turbo speeds in excess of 230 thousand rpm and temperatures around 600 degrees and still keeping going.

Option 1 600cc & 700cc 45kw (55 and 61bhp) Turbo direct replacement
This is the revised standard turbo setup – the new design can be identified by the flats on the webbing as shown
These are much improved.  This 45kw rated unit is  only able to produce about 80bhp max  even when mapping and mechanical mods have been done.  Direct replacement.

Option 2 700cc Turbo 60kw (80bhp) Fits 600cc with modification.
This is the performance version, as fitted to 80bhp models and we have been able to coax 121bhp from this unit with other modifications.
It gives superior torque over the 45 kw one and the power delivery is far more impressive. The internals are a little larger – (+8% inlet and +23% exhaust)
We have managed to max torque from as low as 2700 rpm (101ft/lb ! In a 42). 

This is a great upgrade if your 600cc car need’s a new turbo and manifold.  We get this unit machined to fit the different stud pattern of the 600cc car.  It offers superior torque and  power delivery and we have  600cc Smarts with mechanical mods running 100+ bhp dyno’d.  This can give 20%+ more power over the standard set up

Brabus 74kw 101bhp Turbo
This turbo has a larger volume turbine housing and impeller and compressor wheels as well as ceramic coated turbine housing.  Not currently available for sale in the aftermarket.  This is fitted to the Brabus 101.

Turbo Specifications

Larger turbos and hybrids
There are hybrid and larger turbos available.  We have found the standard turbochargers offer superior torque and power at lower rpm.  The smart suffers from a lack of low rpm - off boost power and subsequently moving the power higher up the rpm range means a loss of drivability.

Turbo maintainance

• Your Turbo MUST have regular oil changes
• On engine start up wait several seconds before boosting the turbo

On engine shut down, let the engine run at idle speed for a short while before turning off the ignition.

How does a turbo work?

• Exhaust gases leave the combustion chamber and into the exhaust manifold and turbo unit where the gas spins a vane on a shaft.
• The other end of the shaft is seperated and sealed and also has a vane fitted – this one causes suction – The faster the exhaust gas spins the exit side – the faster air get sucked in the compressor side.
• The spinning vane compresses the air drawn in the compressor housing and compressed air leaves the turbo housing under pressure.  This measurement is known as boost pressure.  It is refered to in either Bar atmospheric pressure or Psi Pound per Square inch.
• The compressed air is mixed with  fuel to burn inside the engine.  In an engine there is a ratio between the air and the fuel for the engine to work properly.  The more air we can squeeze in - the more fuel we must provide.  More air and more fuel equals bigger explosion in the combustion chamber and more power from the engine.  Thats is why a small turbo charged engine feels like a larger engine when the turbo is working effieciently.
• The boost pressure level is monitored by the ECU (computer) and controlled by an electronic solenoid ( electronic valve) and wastegate actuator ( mechanical valve).  When the boost pressure is high enough – the actuator lets the exhaust gas bypass the exhaust vane (reducing the suction) – the slower it spins – less pressure is produced.
• The term ’Turbo Lag’ refers to the time it takes for the exhaust gas to spin the vanes to make the boost pressure required.  The bigger the turbo - the faster the exhaust gas need to be to turn the larger vanes.  The smart engine being small in capacity does not have much torque.  The engine needs to spin at 2500 rpm for the vanes to be spinning fast enough to provide the boost.
• In the Smart the boost is .8 bar to 1.1 bar  depending on model and year and type (14.50 psi to 1 atmospheric bar at sea level).
• Tuned  Smart cars can run 1.5 bar boost max.  Our remap software writers only use 21 psi (1.5bar) max.
• Some software tuners are still excess boost – this is likley to cause the conrods to twist in the bore – this can result in terminal engine failure.
• The car has a built in mode to stop excess boost – if this happens the car will go into safe mode (no boost get you home mode).