Cummins has revealed its latest Stage 5 100hp to 675hp engines, which it claims are simpler and more fuel efficient than the oil-burners they replace, as it aims to cut down customers’ running costs.

“While most manufacturers are adding technologies for Stage 5, Cummins is changing the rules and reducing complexity,” says Andrew Hobbs, Cummins’ agriculture business director.

See also: How to get a chainsaw’s tired two-stroke engine to run

“Our latest single module after-treatment technology used on 3.8-litre to 9-litre engines is 50% smaller and 30% lighter than the equivalent Stage 4 system.”

More compact

The EGR-free engine design means there is less to cool. It is also more compact, with less weight, which the company says will make it easier and cheaper to install.

Upgrades should deliver the sort of high power density that suits combine harvesters and sprayers, and the power bulge and torque rise should also suit tractors, says Cummins.

The four-cylinder F3.8 and B4.5 engines have achieved impressive-looking increases in power and torque for Stage 5.

The 3.8-litre moves from 130hp to 173hp, while the 4.5-litre engine jumps from 173hp to 200hp. Peak torque of the F3.8 is up by more than 20% to 600Nm, and the B4.5 has increased by 11%, to 780Nm.

Top-rated power for the new six-cylinder B6.7 moves up to 326hp, with a peak torque of 1,375Nm – up 30%. The L9 top rating increases from 400hp to 430hp, together with a 13% increase in peak torque, to 1,846Nm.

Cummins’ Stage 5 heavy-duty X12 engine comes with 512hp and, like the other engines, is EGR-free. Instead, it uses the same DPF-SCR after-treatment system from Stage 4 motors.