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Case Study Minijet Inc.

Written by The Jetlemen | 19.12.2025

Where the journey started

Every partnership starts with curiosity.

When our Belassi team first came across Minijet Inc. and their aluminium jet boats, we were impressed by more than the clean welds and aggressive lines. Their way of communicating, the clarity of their tutorials and the honesty in how they talk about their products showed long experience in a demanding niche and a genuine commitment to their community.

From that first discussion, the goal was clear, combine Minijet’s experience in the mini jet boat world with our engineering know how in PWC powertrains. We wanted to understand if we needed to develop new components, adapt existing specifications, or design a different after sales package that removes the typical complexities between OEMs and boat builders.

The result is a “crate motor” or as we call a marine power unit (MPU) package that is not just a jet propulsion system, it is a 360-degree service for boat builders, from first CAD file integration to long term support to their end clients.

Outstanding in a niche market

The mini jet boat and river boat niche has grown quickly, but the powertrain concept has often stayed the same. Many builders, including Minijet Inc. until now, start from a complete personal watercraft. The PWC donor supplies the whole powertrain, jet pump, controls and electronics. The boat's hull is built around it.

This method works, but it has some clear limits:

  • It is time consuming to disassemble and adapt donor PWCs for every project

  • Builders are not directly supported by the original engine manufacturer

  • Warranty is difficult to manage for the end customer

  • Performance tuning must be done on systems that were never designed for an aluminium jet boat from day one

At the same time, no one in this niche has truly taken the lead in performance jet engines in the 260 to 400 hp segment. Belassi is currently the only Engine manufacturer worldwide offering a turbocharged engine that delivers up to 400 hp in a compact, series produced configuration, specifically designed for jet propulsion applications.

Everything that moves on the water starts with an engine. The best hull design, the most rigid aluminium structure and the sharpest intake lose impact if the power source behind them cannot keep up. It is the inboard engine that gives a boat its acceleration, its character and, in many ways, its soul.

By opening our turbocharged inboard jet powertrain to builders like Minijet, we are doing two things:

  1. We give boat builders a modern crate power unit that is designed from the beginning as a boat powerpack, not as a converted PWC.

  2. We allow their customers to experience a new level of power to weight ratio, reliability and factory support in a segment where most solutions are still based on used donor engines.

Additionaly, we have provided our innovative and tailored after‑sales services as the spare parts catalogue. An advanced 3D live platform makes it easy to order spare parts and access technical knowledge anytime.

Working with Minijet team

Working with Minijet on this integration has been a pleasure.
“From the very first call, it was clear that the team is both knowledgeable and passionate about their segment,” says Sebastian Spring, Project Manager at Belassi. “Their extensive experience was evident when the test engine arrived at the workshop with virtually no installation guide available at the time, yet just a few days later they were ready to hit the water.”

Projects run far more smoothly when working with a team that understands the challenges involved and consistently looks for the best solutions. For that, we would like to thank Jamie and the entire Mini Jet team. We look forward to continuing future developments in jet pump technology to further extract performance from the boats their customers have come to adore.

Statement from Jamie Greenfield, founder of Minijet Inc.

Benefits that elevate the quality standards

The goal of this collaboration is simple, make life easier for boat builders and better for boaters.

1. A powertrain designed for boats up to 6 meters

The Belassi Marine Power Unit is designed for compact jet driven craft, from jet boats up to about 6 meters (about 1500 kg / 3300 pounds), and personal watercraft. This matches the core of the Minijet portfolio, from their A2 series to future projects, where hull length, weight and balance are critical.

For builders like Minijet Inc, this means a ready to install inboard engine and jet propulsion solution that fits naturally into their existing designs, without needing to rebuild the entire boat around a cannibalized donor PWC.

2. Top performance and improved fuel efficiency

The heart of the package is a 3 cylinder, turbocharged inboard engine delivering up to 400 hp. Alongside this peak output, the engine is tuned for efficient jet propulsion. In internal tests we have seen up to 18% lower fuel consumption compared to a similar 3 cylinder supercharged engine, at comparable performance levels.

For boaters this means more time on the river per tank and for builders it means they can position a high performance boat that is also efficient in real world use.

3. Builder friendly crate power unit

The engine package is delivered as a true crate power unit, a complete boat powerpack. It includes:

  • Engine and turbo system

  • Cooling and fuel system components

  • Wiring harness, ECU and open communication protocols

  • Jet pump option and key jet propulsion hardware

Everything is engineered to be ready to install. There is no need for builders to invest time and budget into their own base calibration, wiring or sensor strategy. No additional development or testing loops are required to make the inboard engine and jet pump work together, this has already been done at Belassi.

The package is supported by an official builders friendly service concept. Boat builders have direct access to our engineering team, spare parts, documentation and updates. The goal is to remove the typical grey zone between engine supplier and boat OEM.

The engine package starts at € 14.945 without VAT, giving builders an industrial grade solution that can be integrated into a premium mini jet boat without losing control of their total project cost.

4. Jet pump options and flexibility

The jet pump can be purchased directly from Belassi as part of the same marine powertrain. This makes the whole jet propulsion line a plug and play solution. For builders who already use other systems, the inboard engine can also be coupled to compatible jet pumps, including units based on BRP platforms.

This flexibility avoids one of the biggest issues of donor PWC builds, where pump, engine and electronics must be adapted each time.

5. No donor PWC required

Because the package is a complete inboard jet engine and jet pump solution, no donor PWC is needed. This removes a long list of hidden tasks:

  • Sourcing used or new donor water crafts (PWC's)

  • Disassembling and adapting them

  • Managing individual parts availability

  • Solving warranty issues for the final owner

Instead, builders work with a clean crate power unit that is built and supported as a marine inboard engine from day one.

6. Data logging, live data and CAN based HMI

Modern compact boats benefit from clear data. The Belassi MPU is available with an integrated data logger that can be used as a development tool. Together with our engineers, boat builders can use this data to fine tune intake design, impeller selection and weight distribution in order to optimise boat performance.

For the end user, live performance data such as temperatures, pressures or engine status can be viewed on a dedicated touch display. All main functions are managed via CAN BUS, so builders can integrate the powertrain into their own human machine interface, from simple dashboards to more advanced digital cockpits.