Question on power

[Terry England]

I have an E-tec 90 on a 19' SeaCraft. Yes a 19'. it is an old bowrider that I stripped down years ago to haul freight out to Cayo Costa in Boca Grande.
Remember, when they first built these boats the BIG motor was a Mark 78, 75 HP "tower of power" Merc. Everybody said I needed a 200, but I stuck by my guns. My 19 with the 90 E-tec turning stock Evinrude 3 bladed aluminum props goes as such:
13-3/4 x 15" 3200 RPM - 18 Knots cruise, WOT (4800) 33 Knots 3.8 MPG
13-3/4 x 13" 4200 RPM - 18 knots cruise, WOT (5800) 27 Knots 4.5 MPG
The boat is very light, but this data is with three divers, 7 tanks, two coolers and 70# of ice, plus dive gear. The marina that begrudgingly installed the motor after they took a Johnson V-4 VRO 120 off were shocked at how well the boat ran.
I just ordered a 14" SS pitch (X13-1/4" dia) from Ken at PropGods in Sarasota because the 15" was not letting me turn up full RPM and the 13" had me spooled up to the rev-limiter. There is a picture of the boat on the Moesly web-site under "Proud Owners - 19's". It's the last one on the page.
The secret is that the 90 E-tec is rated at 5,000 rpm and all other E-tecs are rated at 5500 - at 5500 rpm the little 78 cubic inch, harmonically balanced triple make 101 HP! The down side is that they are super-sensitive to water of crud in the fuel. The VRO's were like garbage disposals as long as you disconnected he oil pump!