Sonic ProStock.21 on-road engine

Sonic introduce the ProStock.21 3.5cc on-road engine. Designed especially for club and regional racers the 5-port engine is easy to tune and features a CNC-machined flat piston, optimised crankcase, knife edged connecting rod and turbo combustion camber insert. Other features include a 14mm high-quality main bearing, composite material carburettor with 8mm venturi insert, and lightweight cooling head. Additionally the engine is legal for the Hobby Cup racing series in Germany with more then 20 races all over the country.

Specifications:
– Displacement: 3.49cc
– Power: 2.50 HP @ 36.000 U/min
– Bore: 16.26mm
– Stroke: 16.80mm
– Ports: 5
– Front bearing: 7x19x6mm
– Rear bearing: 14×25.4x6mm
– Glowplug: Sonic S7C turbo plug
– Weight: 325g

Source: Sonic Engines [sonic-engines.com]