904
The initial 2.0 litre Lotus 904 engine was first used in the Lotus type 62 Europa racecar, and indeed used a Vauxhall iron block. The Lotus marketing designation for this engine was LV220 for Lotus/Vauxhall 220 bhp. According to Jeremy Walton this 220 bhp (164 kW; 223 PS) was developed at 8000rpm.
Read more about this topic: Lotus 900 Series