Call Powertech and tell them your issues.. They will suggest a cupped version that will not blow out on turns. Personally, I would stick with a 3 blade on such a light skiff.. You just need some cup to bite on turns..
I had the same issue with blowout with my 2000 Whipray powered by a Tohatsu 50 TLDI tiller using a PT REB3 13" pitch. I sent it to Ken at Prop Gods. For under $100 he had the blade tips slightly cupped. I lost no noticeable top end, but now it stays hooked up, always (including when it's jacked up and running skinny). Give Ken a shout out at [email protected] or 941-735-5808. Ken has always satisfied my prop requests and as a result I will always do my prop business with him. FWIW, he strongly recommended against the heavily cupped 4-blader that PT recommended to me due to the loss of fuel efficiency and top end.