From Chevy Wiki

The 20SEH is a Fuel injection, four cylinder engine developed by General Motors

Intended for the sport segment of Opel, it was offered in the Opel Ascona C GT and the Opel Kadett E GSI featuring a more aggressive Camshaft, and high compression Piston giving it a Horse power and Torque advantage over the 20NE by 10 bhp (7.5 kW) and 5 Nm, the engine feels more lively and has a wider effective power band than the 20NE.

This engine was only available in 1987 along side the 20NE.

Engine	20SEH
Configuration	Inline, SOHC, Transverse 4 Cylinder
Displacement	1998cc (121.88 cu in)
Bore	86.0mm (3.4in)
Stroke	86.0mm (3.4in)
Power	130 BHP
Torque	180 NM
Compression ratio	10.0:1
Valve-Train	Belt Driven, 2 Valves per Cylinder
Engine Management	Bosch, Motronic ML 4.1
Firing order	1-3-4-2