I am ordering a 110% genoa, and when I use the factory "I" and "J" measurements (44'09" and 14'04"), I get a forestay length calculation of 47'. However, when I actually measured the forestay from the spinnaker sheave to the forward bow deck it measures 48'06".

My problem is when I measured my "max luff" on my furler it's 46'03", plus my tack height as 15" above forward bow deck - it adds up to 47'06" which is longer than the factory calculation of 47'00" (which was picked up by my sailmaker - there is also additional length above the furler halyard connection, which is of course also above the genoa head connection).

So I measured my actual "I" height and discovered it is 46'04" (45'02" to coach roof, which is 14" above the deck), and not the 44'09" as spec'd.

Am I measuring correctly? Has anybody else gone through this measuring discrepancy? It appears I'm closer to the "tall rig" specs.

Any suggestions?

Cheers,

Ralph
C36 MK-II (1995)