Prop Recommendation Chart
These are recommended prop sizes classified by engine size.

2 Cycle Engines
.049 - .051 5.5x4, 5.5x4.5, 6x3, 6x3.5, 6x4
.09 - .10 7x3, 7x4, 7x5, 7x6
.15 7x6, 8x3, 8x4, 8x5, 8x6, 8x7
.20 - .25 8x6, 8x7, 9x4, 9x5
.29 - .35 9x6, 9x7, 9x8, 9.5x6 10x4, 10x5, 10x6
.40 9.5x6, 10x4, 10x5, 10x6, 10x7, 10x8, 10x9
.45 - .50 10x7, 10x8, 11x4, 11x5, 11x6, 11x7, 11x7.5
.60  11x5, 11x6, 11x7, 11x7.5, 11x8, 11x9, 11x10
.71 - .80 12x6, 12x8, 13x6, 13x8, 13x10, 14x8
.90 13x6, 13x8, 13x10, 14x6, 14x8
1.08 14x8, 15x8, 16x6
1.20 14x8, 15x8, 16x6
1.5 16x8, 16x10, 18x6, 18x8
1.8 18x8, 18x10, 20x6, 20x8
2.1 20x8, 20x10
2.7 - 3.5 22x8, 22x10, 22x12, 24x8, 24x10, 24x12
4 cycle Engines
.20 - .25 9x4, 9x5, 9x6, 9x7
.40 11x6, 12x6
.60 11x8, 11x9, 12x6, 13x6
.90 12x8, 13x8, 14x6
2.10 14x8, 15x8, 15x10, 16x8

**Prop Recommendations made by Master Airscrew