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Recommended APC props:-
9x6, 9x7 This will allow you to get used to the flying characteristics of the Magnumr with easy launching capabilities.
8x8 This is the most common prop used on the MagnumR with good high speed flight and intermediate launching capabilities. If you require more performance on this prop we recommend you shorten the manifold by 1/2" and the tuned pipe by 1/2" This is only for the 8x8 prop
8x9, 8x10 This is used for maximum speed that the MagnumR is capable of but does require a good launch as the engine does not produce the same amount of static thrust.