Re: double cupped prop
Forget the term 'double cupping'. A modern, aggressive, high-performance prop is already double cupped relative to what cupping (or lack thereof) was at one time.
Double cupping is just a lot of cupping. Most high-performance props are going to have substantial rake and cupping. If your requirements are so aggressive that you are pursuing racing setups, you'll need a prop shop to add even more cupping to a high-po prop, but at this point you are talking about changes so significant it would be to address a special and narrow racing need.
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