The engine in question is the one used in the PS-7900 professional chainsaw, which currently boasts the best power-to-weight ratio of any professional petrol chainsaw in the world – just 1 kg per PS. In standard trim each of these high-performance air-cooled 79 cc units generates 4.6 kW of power (6.3 PS) at 9500 rpm. A specific output of 59 kW per liter is outstanding for a chainsaw, and the secret lies in DOLMAR’s High Performance Combustion (HPC) technology. This term refers to the special design of the six gas exchange ports in combination with the asymmetrical combustion chamber head and the crankcase configuration: the result is a highly efficient combustion cycle with low exhaust emissions.
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