In 2008, F1 introduced standard ECUs (engine control units). Until then, engine manufacturers had used their own ECUs to electronically control their engines, but from 2008, only standard ECUs manufactured by McLaren Electric Systems (MES), which are supplied by the Federation Internationale de l'Automobile (FIA), were allowed. Along with this introduction, traction control (TC) was also prohibited. Until now, when the driver opened the throttle on exiting a turn and the rear tires were about to spin out, TC would reduce the rear tire torque by cutting the engine ignition or by other means, and each team had its own control method.

Honda's TC system powered only four cylinders at low engine speeds, and as the accelerator pedal was depressed, the ignition would be switched in stages to five, six, seven, and eight cylinders. With the mandatory MES ECU, which suddenly switched from four to eight cylinders, cars would oversteer while exiting turns due to the sudden rise in torque. In response, Honda improved the drivability of the engine at partial throttle, before the accelerator pedal was fully depressed, with more concise engine mapping to control engine torque. Engine mapping determines how the torque increases in conjunction with the engine’s output, and is finely tuned for each driver and circuit. Drivability was improved by optimizing this mapping for each circuit for three parameters: the amount of throttle depression, the engine’s rpm range, and the amount of torque generated.

In 2007, development of the engine was frozen, but in 2008, more components were also banned from being developed. Intake and exhaust systems, which had previously been allowed, were now prohibited “below the air filter” for intake air (i.e., around injectors and air funnels). As a result, only the induction box for the intake system, the exhaust pipe for the exhaust system, and fuel and lubricating oil could be developed. As for fuel, the use of fuels containing 5.75% biofuel had been mandatory since 2008. Biofuel has a lower calorific value than gasoline, so used as is, output is lower. Honda overcame the cause of lower output by reviewing the fuel mix. Other basic specifications were unchanged from the RA807E. Maximum output was over 735hp. Since Honda’s return to F1 in 2000, the engine was three times more durable, while increasing output per liter by 23 percent.

In the 2008 season, these engine improvement efforts continually failed to translate into results races. This was due in large part to a delay in the overall development of the car as a result of the reorganization of the aerodynamics team in mid-2007, as aerodynamics had been an issue.

In response, Ross Brawn, who took over as team principal this year, took the drastic step to phase out the development of the RA108, which could not be expected to produce further results, and to focus on the development of the 2009 car, which would be subject to major regulation changes. The staff who had developed the RA108 were devastated, but in order to achieve the goal of winning the championship, Honda shifted its development focus to 2009 soon after the 2008 season started.

However, in the fall of that year, the global financial crisis swept the world, and the business environment surrounding Honda was also hit hard. Honda had been preparing for the 2009 season, but announced on December 5, 2008, its withdrawal from F1 at the year’s end, without achieving its goals.