This page describes the SOHC 16 valve turbocharged engines which GM introduced in 1997.
The engines used a single chain-driven camshaft and an aluminium cylinder head with a Bosch rotary high pressure injection pump.
[3] The lower powered 82 hp (61 kW) version was soon replaced by the smaller and unrelated 1.7 litre Circle L engine.
The update also included changes to the camshaft and pistons, and the newer unit was smoother.
[4] This update also introduced pilot injection[5] and a variable geometry turbocharger[6] These engines were replaced by the 1.9 litre GM/Fiat JTD[broken anchor].