So let's start this blog with one of the most important items on a boat: the engine. When discussing trawler engines, just like with car engines, the most important factors are type of fuel, efficiency, gallons per hour, and horsepower. In the next several posts we will discuss all of these items and their importance in choosing the best product for your vessel.
The Grampstr's Pride has two Tier 3 Cummins QSB 6.7ltr Turbo marine Diesel engines. In future posts we will discuss the reasons for the Cummins engines, but for today we will focus purely on power.
The Diesel Cummings engines we selected have that original 380 HP and can be boosted to 425HP.
So while on trial with some Cummins Experts on the boat they recommended that we increase from the original factory settings to 380HP which allowed a max output of 1335 LBS of Torque at 2000 RPM. At this horsepower the props would spin at approximately 2890RPM. According to the boat experts this was not enough and it should have ran 3000 RPM. So at the 380HP the boat would not perform to the level of its highest efficiency.
By raising the horse power to 425HP we were able to get our torque to 1424lbs at 2000 RPM. This amount of horse power allowed the propeller to spin at the perfect RPM of 3000 RPM at max speed the engine to perform at an optimal performance.
So once we raised to 425 HP we asked the obvious question:
"Should we give it more power?'
The answer was simple: No! The reason being is that it will not at all help with engine performance. In fact, we were told it would actually make the vessel less efficient. According to the experts, any more horsepower would not result in any more RPM output for the props, which means any extra HP at that point is just overkill and a true waste of fuel. So we just needed a little more power!