Not only did the Honda engineers post a new FIA World Record of 261.875mph(1mile), 261.966mph(1km) for a vehicle in its class (Category-A Group-1 Class-4), it posted a speed faster than any Honda-powered car ever including the record established by BAR Honda F1 car at Bonneville in 2006, by using a 660cc engine based on the three-cylinder powerplant designed for the Honda S660 sports car.
The project “Bonneville Speed Challenge” was internally announced at Honda R&D in Japan in 2015 and 16 members were chosen from a pool of 100 volunteers, including the project leader Keisuke Tsuta, to build the car that would be known as the Honda S-Dream. The goal of the project was very simple: “Achieve world speed record with 660cc engine.”
The team carefully re-investigated every part of the S660 engine and renewed many of them including cylinder block, pistons, crankshaft and valves in hopes of coaxing more than three times the power for which it was designed. Additions such as the replacement of the lower block with a steel unit and reinforced connecting rods gave the unit the rigidity it would need to withstand the record run, and the car completed several test runs in Japan before heading to the U.S.
But as can happen when building racing machines, an unforeseen problem popped up once the team made its first test run on the Bonneville Salt Flats. Test driver Hikaru Miyagi returned after his run and told the team that he could not see properly through the narrow canopy. The vision had not been a problem on the test track due to the abundance of landmarks and road marking, but on the bleach-white expanse of the salt flats, the former Japan motorcycle champion was having trouble keeping the car pointed in the right direction.
So the team took the car back to Honda Performance Development in Santa Clarita, California where they restyled the canopy and most parts of the upper body just 10 days before the first day of the Bonneville. The Honda S-Dream made several strong runs at Bonneville Speed Weeks but was unable to reach the record speed that it sought. But soon after the conclusion of Speed Weeks, Honda was officially invited to Mike Cook’s shoot out at Bonneville to take another run at the record.
The team broke the FIA record mark with a run of 227.776mph on the first day of the shootout, then went quicker on subsequent runs until officially topping out at 261.875mph(1mile), 261.966mph(1km). In fact, the team reached 266mph on one of its runs late in the event, but was unable to duplicate the speed on the return run as required to set an official mark.
With the run of 261.875mph(1mile), 261.966mph(1km), the Honda S-Dream has surpassed the record BAR Honda F1 machine established at Bonneville in 2006 to become the fastest Honda car ever.