A Tiger's mast is about 3' longer than a 17's and the sail luff is probably 18" longer. The foot of the Tiger's sail doesn't have the "upsweep" that a 17's boom requires - it's fairly level.
You'd have to remove the hook on the Tiger headboard, too.
Other than that, it's a perfect fit. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
The 17's bows are very tender laterally - that's why a bow foil is used on the sport version. You'd have to be very careful with the spin that you didn't overload the bows.
