I just received and installed new Warp Drive prop blades on my Challenger II. The new blades are 2 1/8" longer than the original ones and only clear the tail upper support tube by 3/4". I am not sure if the originals were cut or not as I bought this plane used. I have pulled and tugged on the engine to try to get the tips to contact the airframe in any way and can not. I have run the engine at full throttle and all seems oK.
My question is, " is there a set or suggested minimum clearance for this configuration? " I can cut the blades but would rather not after spending $600.00 for them.
I am running a 70 HP 3 cylinder engine with 3 blade hub