"40mph at 4200 rpm"
What's wrong with the 150's? If the answer is just that they don't idle well (clean/rebuild carbs, replace/rebuild the fuel pumps, replace fuel filters, decarb the motors, and replace the plugs). Couple hundred bucks in parts (might be less) and a few hours of time and you'll have some happy motors.
After the late 80's the outboard companies started putting all these stupid sensors/computers on their motors to meet EPA requirements . . . IMO these extra friggin electrical components are always screwing things up.
fuel+spark = power (keep it simple) get rid of the other crap.
For Parts:
Brent Gill
www.DiscountOutboardParts.com
Mon-Fri 9am-6pm CST
PH. # 713-910-6294
(These guys are in Texas)
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