Dick, I think you meant 9 oz and not 0.9, correct?  If so it means that your Vapor weighs 4.7 oz.

The 110 sq inch version would fly at the same speed if it has the same wing loading.  The difference in sizing not being enough to make a noticable difference in Reynolds numbers that you'd see.  So you could allow the bigger model to weigh 110/75=1.46 times as much.   But obviously if you can make the bigger model more like 1.2 to 1.3 times as much so it's got a lighter wing loading then it'll fly that much slower.