I run a 15X4W on an 82. It's installed on a Funtanna 40s. Seems to have plenty of pull out power to me. I'm very happy with it. Tachs 9000 to 9100 when set at 300 rpm rich of peak. I only have a little less that a gallon of fuel run through it at this time. I expect it to increase a little more as it gets a few more gallons run through it. I'm running it on Wildcat YS20/20.