He has a 90.....not the same prop as a v6 150-300 prop. 19 pitch is high for that setup,those cape horns are pretty heavy. Doing the numbers your going to need a 15 pitch to get your rpm's right. I would get a use a powertech
http://www.ptprop.com/index.php?page...mart&Itemid=46 call the prop shop in lafayette. If you buy from them they will adjust the pitch if it still is not 100% right for no extra cost. Should run you about 350 bucks or so....