First off that is to much prop for that engine, second a Master airscrew has less pitch than an APC of same pitch so that MA is more like a APC 14x4-14x5 prop. Going to gas from glow you will lose some power. I would try a APC 13x7 or a 13x8. The 13x8 on glow should be around 9,500 to 9,800.
You might try advancing the timing to see what it does.