125PS per litre
A champion of the NA power per litre arena has to be the Honda S2000. In amongst all these six- and seven-figure supercars and hypercars is an everyman sportscar with one of the most highly-strung engines homologated for road use. It bests the likes of the Lamborghini Huracan STO, Ferrari F12tdf and Ferrari 812 Superfast. At least, it does in its most powerful Japanese specification, which produced 250PS from a 2.0-litre 9,000rpm-revving four-pot. That made for a heady 125PS per litre… in 1999!
Commiserations to the Porsche 911 GT3 RS 4.0 of 2011 and subsequent 4.0 GT3s. All matched the S2000’s figure but the later engines feature further up the list on even better form…