TonyBerkshire
Active member
4 cyl. 3 litre and 135 hp, must achieve 4400-4800 rpm at full throttle under normal load (and will have most hp at 4800). Ol' fashioned carburettor as opposed to injection.
Sterndrive would be Mercruiser Alpha.
Ability to pull toys (and achieve speed) will depend very much on the propeller dimension and the boat GW is crucial (where a prop's pitch equals gears on a bike: Too much pitch and you wont accelerate fast or pull hard, too low pitch and you won't get the highest top speed).
US boats by default commonly are powered in aim of approx. 30 knots top speed, but the calculation is based on "135 horses can push xx load to yy speed". The by far easiest performance gain is by removing unneeded/unwanted weight!
So start throwing people overboard if I want to go faster... got it thanks