What engine evolved into the Power Stroke?
The International engine that started it all was the 6.9 IDI. The indirect injection 6.9 was simple in design, naturally aspirated, made 170 hp @ 3300 RPM, and 315 lb-ft of torque @ 1400 RPM. The 6.9 was released in 1983 and gained instant popularity. So much in fact, that Ford had to ask International to increase production of the engines, a move that produced a great stream of revenue for both companies. Sometime in 1987, the bore of the 6.9 was increased from 4.00 in to 4.11 inches, and the 7.3 IDI was born. It was in 1994 that the 7.3 IDI became a direct injected, turbocharged diesel and proudly named, the “Power Stroke”.
