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A Boost for Smaller Engines

Can a 2.5-liter engine be replaced by a 1.2-liter engine without a loss of performance?

Can a 2.5-liter engine be replaced by a 1.2-liter engine without a loss of performance? Controlled Power Technologies (Essex, U.K.; www.cpowert.com) says combining smaller displacement with its electric supercharger makes such “extreme downsizing” feasible because it gives the smaller motor a low-speed transient torque response time close to that of a larger naturally aspirated engine. At the heart of the system is a switched reluctance drive from Emerson Motor Co. (St. Louis, MO; www.emersonmotors.com) that is said to be better at handling higher operating temperatures at a lower cost than a permanent magnet electric motor. The drive unit powers the supercharger’s low-inertia compressor independent of engine speed, and can accelerate its idle speed of 5,000 rpm to 70,000 rpm in less than 0.35 seconds.