The 4 cylinder Henry J engine is the same basic design as the 4-cylinder Willys engine produced during the 1930's. Over its lifetime it was internally upgraded and a lot of its 1930's negatives (timing, oil or water leaks, etc) were resolved. However, the engine remained what is referred to by some as a "long stroke" motor. For those interested, that means the piston travel up and down in the cylinders was a longer distance (in inches of course) compared to a "short stroke" with less piston travel. Long stroke engines had more internal friction and wear issues because the distance traveled over time caused parts to wear out earlier than in the short strokes (Ford Motor Company has a good 1954 Ford TV commercial that compared all this between the 1954 Y-block engine and the previous flathead V-8 motor that had a longer stroke-I have it in my old tv show collection). The 161 cubic inch six represented a refreshing new approach for the company and was a short-stroke motor...another good reason to have a Corsair Deluxe. It remained a short-stroke motor in the F-head version while the 4 cylinder F-head was still a long-stroke motor.
Like a number of European car companies producing compact 4 cylinder engine cars, the rear end in a 4 cylinder HJ had to be geared in the range of 4.5:1 in order to provide proper ramp-up to regular operating speed (having owned an FB series Vauxhall Victor I understand the why of all this). Overdrive on a 4 cylinder helped a lot (final gearing down to around 3.19:1 when engaged) and you had the kick-down switch for hills and mountains where you needed power to the wheels more than you needed speed.
It should also be noted that when the Recovery Finance Corporation (a government agency) granted K-F's loan application in 1949, they put a number of clauses in the agreement that covered design and performance specifications of the Henry J in its basic form. The RFC specified that the compact car had to be able to maintain a top speed of at least 50 miles per hour, which the car could do, but I start getting concerned in one if you go past 55.
