The Ford Inline Six 250 is a 4.1L 250 cubic inch straight six-cylinder that was the optional engine available with the 1969 Ford Mustang. The Inline Six 250 would become the standard engine offered by Ford with their Mustang in 1971 and was rated at the time for 155 hp. This same engine would be rated at 98 hp in 1972 and this rating would drop to 88 hp in 1971. You can recognize the Inline Six 250 by five freeze plugs on the side of the engine block and the seven main bearings included with this engine. The Ford Inline Six 250 is essentially an Inline Six 200 that has had the stroke increased from 3.126 inches to 3.91 inches. These changes to the Ford Inline Six 200 have the effect of increasing the horsepower of the original Ford Inline Six 200 engine to 155 hp and 240 ft lbs of torque.