As BMW themselves produced a 116i 2.0ltr version parts shouldn't be to hard to track down use realoem get a list and see if finacially it's viable
There is always the old syaing by Carol Shelby when a guy asked him how fast a Shelby Cobra was, His answer, "speed costs money son how fast can you afford to go"
Remember back in the 70's Brabham Racing were using BMW 1.5 ltr engines in their F1 cars two turbos (1 big and 1 very big) 900/1000hp in race trim 1200hp for qualifying. The engines were standard blocks selected customers ran them on the road to get heat cycles into the blocks. Customer engines were swapped and the blocks went to Brabham.