To convert a stock Continental O-470 to a O-470-50 SUPER EAGLE several internal changes need to be made to the engine. First, and most obvious is to exchange the O-470 cylinders for O-520 cylinders which increases engine displacement by 50 cubic inches. O-470 models R and S require a new crankshaft. The crankshaft counterweights are reconfigured and case modifications are made. The cylinders are fitted with low compression pistons which are precision balanced to within .5 grams. The carburetor is also modified. All original external accessories are overhauled and used on the O-470-50. The end product is essentially a O-520 which is carbureted and derated to 265-275 hp. Recommended TBO for the O-470-50 is 2,000 hours.