VW up!
The three-cylinder is a successful combination of tried and tested, affordable new solutions and even omissions. Where in other cases, the three-cylinder is given balance shafts, which not only make the engine heavier, but nowadays, also higher. The up! engine manages without these shafts, nevertheless, the engine is still considered to be among the quietest and smoothest in it's class.
A particularly lightweight crank mechanism can get by without balance shafts. |
In the sensitive price segment, it's very difficult to choose between possible components. The pressure will, by the way, become even higher, when in the future, where it will be all about even lower price motor cars. This means, for the up!, doing without charging, direct injection and a varying layout for the two performance stages.
These stages, as once considered for the Mini, will differ only through the software. Basically, the engine with the lower performance will be artificially regulated down when 4500 rpm are reached. The reason for this is, that most of the buyers still make a choice depending on performance and not torque. For those who don't want to 'red-line' the engine all the time, the more reasonably priced model would be the better choice.
At least the engine features a multi-point manifold injection, four valves per cylinder and an adjustable intake camshaft. The individual cylinders, which have the perfect capacity of 333 cm3 are made of cast iron which is thus cased in aluminium, so that a ridge-free cooling area (open deck) remains. The structures with their lightweight bridging on the outside of the engine block remind one more of a gothic cathedral than a cast iron component.
To avoid the oil-pump being shifted to a lower position, it now embraces the crankshaft. The oil-spray nozzles for the underside of the pistons are still unusual in not particularly high-performance engines. In the meantime, long-life timing belts are state-of-the-art. They are no longer as highly pretensioned as in the past, indeed, through their eccentricity, the tension is increased at the opening point of the intake valve.
The module with the camshaft, which is only replaceable as a whole, forms the upper part of the cylinder head, which in the meantime, also in the larger VW-engines, houses the exhaust manifold. Thus, after starting the engine, it's warmth can be utilized earlier. Apart from that, there are two coolant circuits, the stronger of which is used when the full power is applied. In this case, a sufficient distance from the knocking-limit and a little additional injection is important. 06/13
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