Allison Grand Sport: Features, Details and Testing
We made a video taking a closer look at the Allison Grand Sport. There are quite a few unique features and designs in the 20’ hull. Known for its speed and efficiency, there are also some great features that make it fairly practical too.
Some of the key features are the storage compartments. This Allison has tons of storage, making it truly a family performance boat. The bow area has a huge open space for gear, and each side panel has large storage areas. Another cool feature not in the video, is the boat has two hidden compartments in the rear passenger armrests. Plus, the rear deck has 2 large compartments on either side. The middle hatch opens to the tank and rigging. Large compartments are lockable as well.
For the video we have a short rundown of the custom cut “Allison Cut” Trophy Plus 26” prop. This prop doesn’t have enough pitch for a high speed run, but with 5 people on board, we ran it all day and loved how it accelerated and handled. The smaller diameter makes is an efficient prop that makes the boat seem agile and sharp. Not that it doesn’t with the ProMax prop, but the Trophy is very forgiving overall. If you have a bunch of people and gear in the boat, it’s nice to have that lower pitch, we found we could cruise at a pretty high speed and the engine is never bogged down or struggling.
Our cruise numbers with a full tank were pretty good. For lower speeds, they aren’t quite as good as the 28” and 30” ProMax, because that’s like running in overdrive, but as we went faster, the Mercury 150 four stroke put up some pretty impressive numbers.
Fuel Economy
44 MPH @ 3800 RPM = 8 MPG
50 MPH @ 4100 RPM = 7.93 MPG
60 MPH @ 4800 RPM = 7 MPG
65 MPH @ 5200 RPM = 6.4 MPG
As you can see, we lose MPG at higher speeds, but at 4800 RPM, and even 5200 RPM, the 3.0 liter Merc is not working too hard, and really moving. Getting around 7 MPG at 60+ MPH is not bad in a boat. Another advantage of the Mercury four stroke, is that it is so smooth throughout the RPM range. And, it is nice and quiet from inside the boat. At slow speeds it’s virtually silent. It’s not the fastest, but it’s low maintenance, super reliable, not expensive to buy and economical to run. I like the trade off.
The Livorsi gauges look and work great on the Allison Grand Sport. Some pretty decent numbers here.
The Mercury 150 HP four stroke works well on this hull. If it had solid mounts, and higher gears, it would be excellent. Being only a 150 HP, you give up top speed, and acceleration, but the new engines are so quiet and efficient. There is very little maintenance, making the Mercury outboard economical to operate.
