I've got a 1997 Mercury 115 4-cyl 2-stroke outboard on my 27' pontoon. It is a 2+2 motor. <br /><br />The motor runs great below 2000 rpm (in 2 cyl mode) and also above 4000 rpm up to wide open throttle at ~5000 rpm. Between where the bottom two cylinders kick in at ~2200 rpm to 3800 rpm, the...
