Heat oven to 325 degrees F.
Whisk together flour, sugar, baking powder and salt into large bowl. Make well in center; add oil, egg yolks, 1 cup mango nectar, the vanilla and lime rind to the well. Beat with a spoon until smooth.
Using clean beaters and in clean large bowl, beat egg whites, lime juice and cream of tartar until stiff peaks form, about 5 minutes. Gradually pour flour mixture over beaten whites, gently folding in with rubber spatula just until blended; be careful not to overfold or whites will deflate. Pour batter into ungreased 10-inch tube pan with removable bottom.
Bake in 325 degree F oven 55 minutes or until top of cake springs back when lightly touched. Immediately invert pan; let cake cool in the pan until it reaches room temperature.
Turn pan right side up. Run thin knife or spatula around outside edge of pan to release cake; rap pan sharply on counter to loosen cake. Turn cake out; remove bottom of pan.
Meanwhile, pour remaining 1/2 cup mango nectar into microwave-safe medium-size bowl. Sprinkle unflavored gelatin over top; let stand 5 minutes to soften. Microwave on high power 30 seconds or until gelatin is dissolved. Pour in heavy cream and sugar; place in freezer for 10 minutes or until the liquid is cool to the touch.
Peel mango with vegetable peeler. Following line of pit, slice flesh from pit. Remove any excess mango flesh that may still be attached. Chop enough fruit to equal 1/2 cup. Slice remaining pieces into 24 slices.
Beat cooled mango nectar-cream mixture until stiff peaks form. Fold in chopped mango. Slice cake in half horizontally. Place bottom layer on platter. Spread with 1-1/4 cups whipped mango cream. Fan 12 slices fresh mango on top. Stack second cake layer on top. Spread top with remaining whipped mango cream. Decorate the top with the remaining sliced mango and lime rind.