 Complete the following phrase:  For the 1968 season a B specification T86 was produced to incorporate the BRM V12 which replaced the ageing Maserati unit and made its debut at the second race of the season in Spain. Two cars were initially constructed, a third being built after Redmans crash at Spa, and these were used exclusively by the Cooper works team during the 1968 Formula One season. Coopers version of the BRM V12 was a less powerful sportscar version of the engine, which was already one of the heaviest on the grid, but after finishing third and fourth thanks to the unreliability of others in both Spain and 