Once again time to mod new Ski, 19 FX Cruiser SVHO. It has been a long time debate wether for the FX the 13/19 works better than the 13/18 prop (because of pump tunel I think). Any imput?

its for a recreational ski, to get the most out of the stock wheel, with retainers, intake, IC, etc. Everything but stock weel. Some races among friends so need the most top speed but mainly recreational, lakes and off shore.