Mecanica

P.1 of 9 69. 1986C Honda RA166E; 1,494cc; Q 1,200HP* @ 12,000RPM 70. 1987 Honda RA167E; 1,494cc; Q 995BHP @ 12,200RPM 71. 1988 Honda RA168E; 1,494cc; Q 676BHP @ 12,500RPM See Figs. 70A, 71A and 71B, attached. Power Curves for the RA167E and RA168E are also attached. It is worthwhile to consider the history of Honda engines in other branches of motorsports before describing in detail the Grand Prix engines of 1986 -1988, because of the large impact that they made on high-power engine design. The first Honda Grand Prix motor-cycle racing era, 1959-1967 Soichiro Honda founded his firm to make lightweight motor-cycles in 1948. In 1959 the 1st entry was made in a major International race with a 125cc twin-cylinder machine. A 250cc four followed in 1960 and in 1961 each took its World Championship. From then until the end of 1967, when the company retired from Grand Prix motor-cycle racing for a time (which turned out to be 12 years), they campaigned in all classes from 50cc to 500cc in various years, providing mounts for 16 Champion riders (only the “Blue Riband” 500cc escaped them) and captured 18 Makers’ Championships (all 5 classes in 1966). All the Honda racing motor-cycle engines were 4-stroke air-cooled and had 4 valves per cylinder (4v/c) – this latter feature was re-introduced by them into that arena (see Note 78) – which coped easily with Bore/Stroke (B/S) ratios gradually increasing from 1.07 to 1.41, but with wide included angles between valves (VIA) varying from 760 to 560 which did, however, allow airflow to the top of the cylinder head. Honda specialised in miniaturisation, raising volume specific power (HP per litre, HP/L) by reducing S and increasing the number of cylinders (CN) – except for a modest 4 cylinders for their 500cc, where the engine in any case easily gave more power than the frame and tyres could handle satisfactorily. Honda reached 263 HP/L @ 20,000RPM with their 1966 RC149 IL5 125cc design (354). The downside was an RPM range for that