The McLaren MP4/5, and its derived sister model, the McLaren MP4/5B, were highly successful Formula One racing cars designed by the McLaren Formula One team based in Woking, England, and powered by Honda's naturally-aspirated RA109E and RA100E V10 engines respectively. The chassis design was led by Neil Oatley, teaming up with Steve Nichols, Pete Weismann, Tim Wright, Bob Bell and Mike Gascoyne. As with the previous designs, Gordon Murray, as Technical Director, had the role of liaising between the drawing office and production. Osamu Goto was the Honda F1 team chief designer for the car's engine. The MP4/5 was loosely based on its predecessor, the all-conquering MP4/4. McLaren used the new car for half of the season using the Weismann Longitudinal Transmission from the MP4/4, and the MP4/5B with the Weismann Transverse Transmission for the last half of the 1989 season and for , earning back to back drivers' and constructors' world titles with the type. Over the course of two seasons, the MP4/5 took 16 wins, 36 podiums, 27 pole positions, and 263 points before it was replaced by the MP4/6 for . 1989: MP4/5 1989 was the first year where naturally aspirated engines were compulsory for all teams after the banning of the turbocharged units at the end of the previous season. To this end, Honda built a 3.5-litre V10 engine, developed throughout most of the latter half of 1987 and through 1988. The MP4/5 was unveiled for pre-season testing and it was instantly on the pace, as well as reliable. Developed by Neil Oatley, the MP4/5 looked like the car to beat in the new season. While the Ferrari that season was a fast all-around car particularly in the hands of Nigel Mansell, it was also chronically unreliable due to its new semi-electronic gearbox shift, giving a further advantage to McLaren. The Honda-powered MP4/5 proved to have the outright pace over the rest of the field, with fifteen pole positions, thirteen of them by Senna which equaled his 1988 record in the MP4/4. At the Mexican Grand Prix, Senna scored his 34th career pole in the MP4/5, breaking the previous record of 33 held by the late Jim Clark that had stood since . McLaren took ten victories during the season, six for Ayrton Senna and four for Prost. This was at a time when the relationship between the two men was at its breaking point, so