Vale Paul Rosche: BMW’s engine genius

Engineers rarely enjoy celebrity status.

But BMW engineer Paul Rosche – who passed away this week aged 82 – is known for producing some of the greatest production and motorsport engines we’ve ever seen.

Munich-born Rosche worked for BMW from 1957 to 1999, credited with some of the brand’s most renowned mills that lived in McLaren’s F1, BMW’s Formula One cars, and also its most iconic M Machines.

We salute the man with a roll-call on some of his finest achievements…

1. Brabham BT52 1.5-litre turbocharged four-cylinder

BMW credits the “dogged determination” of Rosche for getting the brand back into Formula One in 1980. His creation, the M12/13, may not have been first to go turbo – Renault was – but it was the first forced induction motor to win the motorsport championship.

Touted as the strongest F1 engine ever, the ‘official’ circa-600kW 1500cc unit powered the scary-fast Brabham BT52 driven by Brazilian Nelson Piquet to victory in the 1983 championship.

Of the maximum output potential of this hi-po four, Rosche said: “It must have been around 1400hp [1044kW]; we don’t know for sure because the dyno didn’t go beyond 1280hp [955kW].”

2. McLaren F1 6.1-litre V12

The S70/2 engine for the 1993 McLaren F1 is regarded as Rosche’s high watermark. Few components were shared with BMW V12s that had come before – despite S70/2 being a naming extension of the S70 5.6-litre used in the 850CSi – and the F1’s 6.1-litre made 461kW at 7400rpm and 651Nm at 6700rpm.

With dual variable-valve timing, 12 individual throttle bodies, carbonfibre airboxes, a quartet of oil scavenger pumps and dual fuel injectors per cylinder, the dry-sump unit beat its imposed power target by 15 per cent, though weight fell 16kg beyond the 250kg target.

This was 1993 – but the V12 went on to win LeMans for McLaren in 1995 and BMW in 1999; the latter Rosche’s retirement year.

3. BMW E30 M3 S14 four-cylinder

Rosche had been tinkering with the M10 four-cylinder block that traces back to 1968 and for the E30 M3 engine merged the four-valve head from the M88 six-cylinder powering the E28 M5, M1 and others.

Individual throttle bodies, machined intake and exhaust ports and compact dimensions helped make the S14 a proper motorsport-ready and free-revving engine.

From its 2.3-litre capacity the 1986 M3 produced 143kW at 6750rpm and 240Nm at 4750rpm – the latter more than 100Nm per litre, and this from 30 years ago.

Before finishing production in 1990, the final M3 Evo was enlarged to 2.5 litres and produced 175kW at a heady 7000rpm.

Vale Paul Rosche, April 1 1934 - November 15 2016.