oil pressure throughout thanks to a crack in the engine block that was only discovered when the team stripped down the car and engine after Dick had raced it in the Group A support race at the 1986 Australian Grand Prix meeting in Adelaide. The Mustang also had a cracked windscreen from which had been there since before Hardies Heroes, and like 1985 before he left the circuit for the night Johnson instructed the team to change the windscreen. Upon returning to the circuit on race morning an angry Johnson found the cracked windscreen still on the car with no time to change it before the race, though thankfully the crack did not spread during the race. Johnson's last drive in the Mustang came in the Group A support race for the 1986 Australian Grand Prix in Adelaide. After qualifying 8th, he failed to finish the 32 lap race. Sierras In 1987 the team switched to the Ford Sierra RS Cosworth and began a 17-year run of naming rights sponsorship with petrochemical company Shell. It expanded to a two-car effort for the first time with Gregg Hansford becoming Johnson's first full-time teammate. The new , turbocharged Sierra's were plagued with reliability problems, usually blown turbos (according to Johnson in a 2015 interview with Australian Muscle Car magazine, DJR went through some 37 turbochargers in testing and race meetings in 1987), and this let the team down considerably, with only one win recorded in the 1987 Australian Touring Car Championship at the Adelaide International Raceway (Dick's first ATCC win since 1984), though significantly this was the first Group A win anywhere in the world for the RS Cosworth. Following the ATCC, the Ford Sierra RS500 was homologated which addressed most of the car's shortcomings. The RS500 was more powerful ( in 1987) with larger turbos and was also more reliable. The team's poor run continued at the Sandown 500, where Johnson easily qualified his new Sierra RS500 on pole but the car blew its engine in the race morning warm up and was withdrawn, and Bathurst 1000 where both team cars were out of the 161 lap race before the end of lap 4 (Neville Crichton crashed the No. 18 Sierra he was to share with Charlie O'Brien on the 3rd lap with the Commodore of Larry Perkins which the Johnson / Hansford car suffered differential failure a lap later). Qualifying