I posted this on the SuperCub forum and had some great feedback. Thought I'd post it here also as this is the J3 forum.
Finally we have completed majoring my C90-8 for my 46 J3C landplane. I bought a new McCauley Cm 7443 for the 65 that is in it last Fall, and it has about 40 hours on it. I was led to believe it would be a simple matter to have my AI do a 337 form to use it on the C90. Seems that ain't so. That prop is certified on a C90 in several aircraft at a length not to exceed 73". The plan was to have New England Propeller cut it down an inch and use it on the C90. The problem is that while the prop is certified on several aircraft with a C90 it is not certified on the J3C with a C90. My AI doesn't think the FAA will buy a 337 field approval.
So I am kinda stuck. I would like to use as long a prop as possible as I have been told that a longer prop will get you up and out better. The only legal prop I see is a McCauley CM 7148. Sensenich doesn't even list a prop for a J3c with a C90.
I would like to hear comments on what other members are using .......
Thanks for any help..