Suzuki has changed the gear ratio on the df140's from 2.38 to 2.59. Right now I am using a pair of the 2.38's but I will need a new engine soon and it looks like I will have to go with a 2.59. I will have to buy a new 2.59 bottom end for the older motor.
My boat tops out between 5200-5400rpm with a full load 13up + 400 litres of fuel. The df140's max rpm is 6100-6200. If I go to the 2.59 and use the same props I think I should get a little more rpm and speed.
A quick guestimation you should gain ~500 rpm going by the ratios alone, for your present top speed.
whether or not you could then get up to your engines rated max rpm and go faster depends on what the power curve does up at that rpm range.
you may already be at the peak.
Can someone precise the standard (medium range) propeller size for the 65 HP some years back old engine, the one that was currently factory delivered with. Thanks in advance.
Can someone precise the standard (medium range) propeller size for the 65 HP some years back old engine, the one that was currently factory delivered with. Thanks in advance.
If it's a late 80s/early 90s DT65 3 cylinder motor, then they came with a 15" pitch prop as standard.
