Cosworth engine technology

“To go faster you just have to keep making the bore bigger, the stroke shorter and sort out your valves...” Cosworth technical director Bruce Wood’s turn of phrase is worthy of Keith Duckworth. Race Engine Technology reports on the first Formula One engine to reach 20,000rpm, the Cosworth CA of 2006 and it seems unlikely anybody went faster before rev-limiting. The naturally-aspirated 2.4-litre V8 CA is now in the Marussia, disputing the back of the grid with Renault-engined Caterham. RET editor Ian Bamsey recalls that since 1906 grand prix engine speeds rose from less than 2000rpm to 20,000rpm until progress was halted with a 19,000rpm rev limit for 2007. This was reduced to a (relatively) stifling 18,000rpm, together with a moratorium on development but evolution is back for 2014. In deference to greenies its goal will be fuel efficiency, rather than outright power.

Speed and horsepower climbed with the 3.0-litre V10s, before the switch to V8s for 2006. BMW probably reached 19,000rpm first in 2002 but engines had to do bigger mileages in 2004 and 2005. The top 2005 V10 was the Toyota, which ran to 19,200rpm and produced 930bhp. All the 2005 V10s exceeded 900bhp, probably not more than 950bhp except possibly the Honda.

Bamsey describes the astonishing performance of a Formula 1 engine. At 20,000rpm, the CA's piston acceleration was 10,616 g, while the load on each crankpin by piston and conrod reached 5937kg. Ballistic missiles can only manage 100g, while 5937kg is about two and a half times the weight of a Rolls Royce Wraith.

Race Engine Technology's full report of the Cosworth CA, in issue 73, spans 27 pages and can be bought from www.highpowermedia.com, or by calling Chris Perry on +44 (0)1934 713957.
Cosworth CA (top) and its great predecessor the Ford-Cosworth DFV (right)