The full inside story of Senna's Indycar test This week marks the 25th anniversary of Ayrton Senna's 1992 Penske test in Arizona. To mark the occasion, here's an Autosport feature from earlier this year - the full story of the "amazing" occasion, told by the men who were there 1494979200 F1

The Indy 500 engine they had to outlaw Undefeated and never to be repeated. The story of how Penske's Ilmor-Mercedes engine for the 1994 Indy 500 went from top-secret evening project to dominating the Brickyard to banned 1483315200 IndyCar

The top 10 IndyCar drivers of 2016 Simon Pagenaud and Team Penske dominated the 2016 IndyCar season, but they were not the only drivers to impress over the course of a tough campaign 1474934400 IndyCar

Why is IndyCar shelving its manufacturer war? Competing IndyCar manufacturers Honda and Chevrolet will revert to only being engine suppliers in 2018, and aero kit development has been halted for next season. Why has the series removed an area of competition that was only recently adopted? 1474416000 IndyCar

How Formula 1 arrived at its vital crunch meeting Ross Brawn has spearheaded Formula 1's increasingly hands-on approach to defining the next generation of rules. But will his method pay off in this week's critical meeting? 1553472000 F1

How Ferrari and McLaren gave F1 an incurable headache At last year's Japanese Grand Prix, the re-emergence of tobacco sponsorship was evident at Ferrari, and McLaren's BAT deal followed for 2019. The return of such sponsors means F1 must consider the wider impact 1553472000 F1

The importance of short-circuit racing for TT success Isle of Man TT riders using short-circuit races to warm up for the main event is nothing new, but the success of some relative newcomers to the TT in recent years has resulted in a more seismic shift in preparations 1553385600 TT

Why bringing back the ‘toys’ could make F1 closer Putting control back in the hands of the drivers has often been a simplistic answer to F1's lack of close racing. But ex-Lola and McLaren engineer Mark Williams explains why a return of sophisticated gizmos could solve the issue 1553299200 Engineering