Culprit’s Repower: More Power, Less Fuel, and Smoother Performance

When Steve, the owner and builder of Culprit, first launched his custom-built gamefishing boat in 2024, he knew she could perform better. Despite looking the part, the original engine wasn’t delivering the power or fuel efficiency needed for long offshore days. “We were burning up to 16 litres an hour while trolling and almost 60 litres cruising,” Steve explains. For a boat that spends 12 hours a day at sea, it just wasn’t sustainable.

As a commercial skipper and maritime police officer, Steve knew exactly what he needed: more torque, better efficiency, and a compact, easy-to-service engine. The NANNI T4.270 was the perfect solution. Delivering 265 HP and an impressive 660 Nm of torque at 2200 rpm, it provides the pulling power of a larger block in a lighter, more efficient package. “The torque of the engine is just phenomenal,” says Steve.

The installation process was simple, just a minor adjustment to the engine bed and the new NANNI slotted straight in. “We wanted a bolt-in, bolt-out option that we could maintain ourselves at sea, and the NANNI made that possible,” he adds.

The transformation has been remarkable. Culprit now cruises comfortably at 22 knots at just over 3000 rpm and can reach 32 knots at full speed, all while operating at only 60% engine load. Fuel burn has more than halved: from 16L to 3.7L per hour while trolling, and 60L to 30L per hour when cruising, meaning more time fishing and fewer refuelling stops.

Quiet, efficient, and powerful, the NANNI T4.270 has completely changed Culprit’s performance, proving that the right repower can bring a great boat to its full potential.

Watch the video below to hear directly from Steve!