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List of VM Motori engines - Wikipedia
"425 OHV
2.5 L; 152.5 cu in (2,499 cc) straight-four, with two (pushrod-actuated) valves-per-cylinder and indirect fuel injection. 92 mm × 94 mm (3.62 in × 3.70 in), the engine size is variably referred to as either 2,500 or 2,499...