According to JCB, Sisu engines have been specially developed to give the sustained high power and torque levels demanded in a heavy draft tractor.
It says engine torque has increased from 949Nm to 1015Nm on its Fastrac 3230.
The engines also feature a transport-boost facility which can be selected by the operator increasing the normal maximum power output of 145kW (195hp) for the 3200 Xtra to 172kW (230hp). The standard 172kW (230hp) output of the 3230 Xtra is increased to 200kW (270hp).
SCR (AdBlue) is used for exhaust emission control as opposed to the other accepted method of combining Exhaust Gas Recirculation and a Diesel Particulate Filter.
The firm claims that this system benefits the end user with improvements in fuel consumption and reduced in-cab noise levels.
The new Fastracs don't just feature a new emissionised engine; improvements also include a new Road Performance Package and new anti-lock braking system (ABS).
The Road Performance Package includes traction assist and hill hold. The former uses torque and brake control to prevent wheel spin when turning into a field gateway or pulling away on loose ground.
Hill hold keeps the brakes on after the driver has pressed and released the pedal. The brakes are automatically released when the tractor moves off, which JCB claims makes hill starts easier to handle.
Both Fastrac models are being upgraded to 540/65R34 tyres all round as standard and a 600/70R30 tyre with the same rolling circumference becomes the widest and tallest factory-fitted tyre option.
New mudguards front and rear cover more of each tyre and reduce the amount of water and mud sprayed on to the cab and windows, the firm says.
JCB uses its own P-Tronic semi-powershift transmission, which was introduced on the 3200 Xtra and 3230 Xtra Fastrac two years ago.
It is a power-shuttle, 24 forward/nine reverse gear transmission incorporating six powershift speeds, three more than were previously available.
Three different transmission settings give operators a choice of manual and two auto-shifting modes, one for the field and one for the road.
On the road, another feature from the firm is Xtra-Drive, which allows the operator to ignore the clutch pedal and drive the tractor like an automatic car.
JCB says it has introduced what it describes as a new 'light action bonnet' with removable panels and right hand, low-level service door.
These provide easy access for service and daily checks.
The new tractors are 'guidance ready' according to JCB, so that operators can easily add a full-feature auto-steer system.
This can integrate with other automated functions through the tractors' touch-screen terminal introduced with the Xtra specification last year.
These include Headland Turn Assist, which allows up to 15 different control actions to be assembled and linked for instant or delayed reaction (determined by time or distance) into sequences for five different implements.
JCB says that LiveLink will be available on Fastrac tractors and other JCB agricultural vehicles in the coming months to securely collect machine status and other data that owners can access online by computer or smartphone.
This data includes fuel usage, engine hours, time spent at idle and under load.
This will allow an owner to compare the performance of similar machines (and operators) to better manage how the machine is used in field, on the road or for scheduling servicing or refuelling. The firm also says it will be possible to call up a trace of a machine's movements and set up a geo-fence that transmits an email and/or text alert if the machine moves out of the designated area.