The engine on the Curtis pusher is an OX-5 V-8
Originally the First Curtis airplanes offered a 4 cylinder and 8cylinder engine. The Rheims Racers winner of the Bennet cup in France in August of 1909 was powered by a V-8. Other planes that were sold to the public had a lower powered 4.
This engine was built for the Army in 1919 . It has 90 HP and ticks over at 1,400 rpm.
In ordered to remove we had to pull the top wing and hoist the engine out.