[Doug I]

ummmm macaroni is hollow .......

that'll introduce a Diam^2-diam^2 term in there won't it ..... if it's volumn ....... which for macaroni is important (especially at lunch)

you wanted the footprint of the macaroni ? in plan if I'm reading it correctly.

Will need cyl. bore, piston dia., ring end gap, inner ring dia. and piston ring groove inner dia. After that it's easy.

That let the range of areas be calculated.