Gas Power Boxes
A gas powerbox can only be used on 2-stroke engines. The powerbox (placed between the carburettor and the cylinder or between the carburettor and the reed valve) works as a recovery tank for the excess induction gases. When the induction phase is completed, some of the fresh gases which would otherwise have been dispersed, fill the powerbox, and then, when the piston rises again and the induction phase begins, the gases accumulated in the powerbox are released and join the main flow coming from the carburettor. This procedure improves the engine torque during the transition phase from low to high revolutions.