In terms of performance, if we maintain the regime with 100 turns above in the gas engine, the benefits are quite equal compared to the diesel engine.

By Silvio Pinto. – Volvo Trucks has put in our hands his last realization, the G13, a mechanic that on his well-known bench of thirteen liters operates with natural gas, although maintaining the diesel cycle, and with a performance very close to the variant that uses only diesel. Let’s see below its theoretical and practical characteristics.

The new G13 engine uses the well-known 12.8-liter bench with which the Swedish manufacturer has been motorizing
to its FH, FM and FMX ranges during the last years. It is a block of six aligned cylinders of 131 mm in diameter with a displacement of 158 mm, resulting in some remarkable maximum torque figures from 900 rpm (we are talking about the diesel versions, of course), in relation to their corresponding power ranges. It requires 33 liters of lubricant for good performance (including oil filters), and 38 coolant for optimal temperature control. Those that are currently commercialized receive a K in their name, which indicates that it is the latest evolution in diesel.

Imagine that these renowned engines are incorporated a new circuit that ends in the “same” injector, but through which circulates natural gas from a tank that allows storage at low temperature, and then discuss in detail. Imagine that the new fuel is incorporated into the discipline of the diesel cycle, always accompanied by it (between 5 and 10% to facilitate its burning), and that its performance is very close to that offered by the aforementioned D13K. If we have been able to imagine all this, we are in a position to know the new G13.

On Route

The first difference that we can assess from the new mechanics is its acoustics. It is not a radical change, but it is clear that they sound slightly more “fluted” than the diesel with a less harsh purr but not too far from the D13K. In terms of loudness, the slight change in tone invites us to think at first that the gas propulsion subtracts some decibel at equal speed. However, it would be more fair to compare this parameter equalizing the performance of the engines, and since the G13 needs around 100 more turns to “equalize” the performance of the diesel, we would be talking, at least, of a technical tie to the zone average / low of the rev-count.

Out of the green zone (above) the tables are slightly changed, in any case appreciations of shade. In terms of performance, if we maintain the regime with 100 turns above in the gas engine, the benefits are quite equal. If, on the contrary, we work with the same regime, the D13K imposes its law in the lowest zone of the tachometer, taking a partial rematch the new LNG was already of the usual working regime (1,600 rpm). These peculiarities are manifested to a greater extent among the mechanics of 460 hp.

05/01/2018 – ALL TRANSPORT (Translation Soft)