Twin-cam Diffin: A History

The Toyota Twin-cam was created by the infamous Japanese engineer Issei Sagawa, a man born prematurely in the forests of the ‘Aokigahara’ or ‘Sea of Trees’ at the foot of Mt. Fuiji in 1956. Sagawa suffered as a child from respiratory illness, it was said that often he relied on his twin sister to carry him on the long walk from school to their home in the forest. Emasculated by his sickness, and cowed by the long distances he was forced to walk, at the age of seven Sagawa vowed that he would one day construct a vehicle which would provide his family with respite from the steep, winding roads of his homeland. As he grew the young Issei’s illness lessened, till at the age of seventeen he travelled to Kyoto to study mechanical engineering. Issei vowed to pursue his craft with an unparalleled determination. The boy dreamed incessantly of returning to his family home, and making his father proud. In Japanese culture the love between a father and his son is known as Diffin, and it is regarded as the most sacred and truest of loves.

Four years passed, and the zealous young Sagawa graduated from Kyoto in 1979 with a distinction in his chosen craft. The Japanese motor –industry at the time was booming; the demand for reliable and affordable Japanese cars among the drivers of Europe and beyond was near insatiable. On obtaining his degree, young Sagawa walked from his graduation ceremony all the way to Toyko. He sought out the sprawling factory districts on the edge of the city, in which was housed the jewel in the crown of Japanese engineering: Toyota. 

Sagawa receiving his degree August 1979

Sagawa gained employment sweeping the debris from the factory floor. He showed himself to be a hard-worker and the company director Mr. Miyagi quickly promoted him to waxing the newly assembled cars before they were shipped for export. Within three years Sagawa had climbed the ladder to success. By the summer of 1982 he was promoted to the position of ‘National Director of Design.’ Remembering his breathless childhood and his parents back in the labyrinthine forest, he immediately set to work in realizing his dream. Issei held twin desires for his new beast, it would be effortlessly able to navigate the unforgiving bends of the forest roads, whilst possessing the ability to ‘breathe’. Throwing caution to the wind, he decided to create a car which was rear wheel drive, a car which would be the last of a dying breed during a time when the motor industry began to favour front-wheel drive passenger cars. The vehicle came with a fuel-injected 4-cylinder twin-cam cc 4A-GE engine. The inclusion of an OHV or overhead ‘twin’ camshaft offered an increase in the engines ability to exchange induction and exhaust gasses- often referred to in the industry as ‘engine breathing’.  Issei’s creation -The Toyota Twin-cam (officially dubbed the The AE86 generation) - was a small, lightweight coupe which was introduced by Toyota in 1983 as part of the fifth generation of the Toyota Corolla.

The Toyota Twin-cam factory, constructed in the shadow of Mt. Fuiji  1986

During the winter of 1983, Issei himself felt proud enough of his creation to brave the long journey home to the forest in Aokigahara, where he could be re-united with his aging parents. His father was known to sit on the porch of their house every day until sundown, eternally in wait of his sons return. One evening as father Sagawa sat in his rocking chair, with the last sliver of sun glinting over its creaking, metallic legs, he heard the roar of an engine in the distance. He rose to his feet, peering down the winding, convulsing road which snaked below on the hillside. In the distance a white motor car roared over the twisting dirt track, its back wheels biting furiously into the reddened soil. In no time at all the vehicle had reached the final bend before the house, careering through the meander with an ungodly abandon. The car hurtled side-ways as if pulled by a great invisible force, the side thread of the tires growling as they sunk into the tundra at an unnatural angle. The monster skidded to a halt. Blazoned across the bonnet was the fire-red decal of the Sagawa family crest. Issei jumped from the cockpit. ‘Father, I have returned’. Old Mr Sagawa opened his mouth, a solitary tear slipping from his eye.‘Son’, he croaked. 'You have filled me with Diffin. This car, its engine, it is the embodiment of our Diffin'.