It seems there’s almost no limit to the power it is possible to squeeze from a modern-day four-cylinder engine. We find out how Massey Ferguson’s biggest four-bore measures-up against an equivalent six-potter from New Holland.

Tractor makers have been fighting to build their biggest four-cylinder tractors over the past couple of years, but farmers have traditionally approached these small-engined powerhouses with caution.

In many buyers’ eyes cranking-up the power from a four-pot doesn’t quite compare to a slow-burning six-cylinder more than capable of outlasting its owner.

However, that extra pair of cylinders adds too much length and weight for general farm tasks. So farmers looking to trim back their tractor line-up without scrimping on horsepower now see the well-proportioned four-potter as the great bastion of farming flexibility.

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Claas, Deutz, Fendt, Valtra and Massey Ferguson are just a handful of the companies to offer four-bore tractors pumping out maximum powers beyond the 160hp-mark.

Most makers go about tuning up their powerplants by bolting on expensive turbochargers. These ram more air into each cylinder and a complicated engine governor dishes out the extra fuel when it’s needed.

The clever common-rail systems are able to get lots of juice into the cylinders at low engine revs, so drivers get the higher power and torque they crave even with the engine running just north of tickover.

On paper it means you’ll get similar torque curves no matter whether you pick four or six cylinders.

However, the proof is in the performance. So, to find out, we pitched Massey Ferguson’s biggest four-cylinder family member – the 6616 – up against a popular six-potter – the New Holland T7.185.

Both have maximum rated powers around the 160hp-mark, drive through a semi-powershift transmission and are closely matched in rear lift and hydraulic capacity.

To get both tractors sweating we paired them up with identical five-furrow Amazone Cayron ploughs, set to dig down 20cm and stretched out at 45cm furrow widths.

New Holland T7

Engine

The New Holland’s Fiat-sourced six-potter is a big lump compared with the triple-triangle’s neatly packed Sisu. The bonnet is long and high, which means the T7 cuts an ungainly figure when sat in the yard.

The narrow Michelin rubber does nothing to improve its lanky looks.

Physically, the Basildon-built T7’s wheelbase measures up 11cm longer, and the extra couple of cylinders and associated gubbins also added 300kg at the weigh-in.

All that extra bulk makes it a little more cumbersome. The turning circle is out at 10.9m, which makes it a full 1.1m clumsier than the Massey, though once you are behind the wheel it is not as oaf-like as it looks on paper.

If traction and pulling power is high on your agenda then you will really reap the rewards of the extra length and weight in the field.

While we had the Massey running at full-chat just to keep up with the 8kph pace, the New Holland’s six-pot settled at a leisurely 1,700rpm.

Despite being shod on narrower rubber it also kept traction where its red rival began to slip. Here it had the advantage of a front linkage and 1t block hanging off the nose to improve balance.

Transmission

One of New Holland’s most basic T7 transmissions is a 19-speeder split across three ranges.

Shifts through the Range Command box are perky, though you’ll find shunts between ranges a little lumpier.

You’ll also have to shuffle through all of the powershift steps before switching range, which is a pain when you’ve got no load on the back and adequate power to leap up several speeds at once.

Gear changes can also be automated by bashing a button on the side console.

In field mode it’ll jump between any number of speeds within a range, while road mode lets it clamber out of B-range and into the higher gears.

Cab

Interior design has never really been New Holland’s forte and it’s the same story for the T7. The Italians have stuck with the drab grey plastics and bog-standard controls, but on the bright side it’s easy enough to find your way around.

Four mechanical spools run along the right-hand console, while rocker switches control the likes of four-wheel drive, diff-lock and the automatic transmission.

Gearbox information is shown on an LCD screen old enough to make an 1980s Casio watch look cutting edge.

New Holland’s Sidewinder armrest is standard on higher spec machines, but for those that stick with the basic model there is a far simpler set-up.

Linkage controls lie close to hand, and quick lift/lower buttons are doubled-up on the rigid handstick.

These work well, though the whole armrest is bolted to the seat so you’ll only really be comfortable if you’ve got arms like a T-rex.

Back end

The T7’s tail end looks a more basic affair than the Massey’s, but with the pair sharing a rear lift a touch over 8t they are pretty well matched.

The downside is that, in New Holland’s case, the four spools run knuckle-grazingly close to the lift rods so they’re a nightmare to pull out.

Massey Ferguson 6616

Engine

Go by the spec sheet and the tractors have almost identical engine ratings, but the smaller Massey started to struggle with five furrows in tow. In easy-going land it could just about keep up with the New Holland, but hit a stiff patch and it dropped back faster than a runner with a wrenched muscle.

We also had to rev the engine hard to get the performance we needed. That resulted in a slightly unpleasant din in the cabin.

On the plus side, the shorter block keeps the dimensions neat and tidy and the turning circle tight. It’s lighter, too, so we’ve no doubt it’ll go much better on trailer and top work.

Transmission

Our tractor was fitted with the Dyna-6 transmission that had a veritable Aladdin’s cave of different driving options and modes.

At its most basic, it runs as a standard semi-powershift with the driver taking charge of engine revs on the throttle and gear shifts using the joystick (T-lever in more basic tractors) or the left-hand shuttle.

Press a button on the right-hand console, though, and you’re into auto-shifting mode. This makes it act a bit like an automatic car, notching though all the gears while the driver uses the foot or hand throttle to control the revs.

Our tractor also came with two optional cruise speeds that let you set the gear the tractor will automatically shift up to as well as the engine rpm.

There are plenty of other settings to play with, too, but unless you delve into the manual, you’ll be spending plenty of time scratching your head figuring it all out.

The goods news is that if you leave all the fancy stuff alone it’s no more difficult to drive than the New Holland. One feature that is worth flicking on is the brake-to-neutral function. This activates the clutch when you stand on the brake, which is particularly handy for loader and baler work.

Cab

Interior fit and finish is another of the Beauvais-built tractor’s strong points. Plastics are tougher than average and in general the controls are pretty well placed.

But it wasn’t perfect. We thought the pedals were far too close together, and the squidgy separate buttons for rear linkage control were a poor replacement for the old rocker switch.

The cab frame itself is quite an old-school design, with six-pillars and curved rear windows. But that is not necessarily a bad thing – we liked the fact that with the more traditional arrangement you get side-opening windows, a good-sized door and a smaller rear window that shuts a bit easier.

Back end

For a four-cylinder tractor, the MF has a decent set of rear links with an 8.1t lift capacity.

Unfortunately our tractor was a bit light on the front end, which made the plough knock it around a bit. But add a front linkage and bigger weight block and it should be fine.

What we think

If heavy pulling is top of the agenda then the New Holland’s six-cylinder engine and extra length is the best combination for power and traction.

There’s no doubt that the Massey is gutsy, but the way it delivers that power makes it less well suited to heavy draftwork than the six-potter.

The result is you end up working at much higher revs and the hum in the cabin makes the job feel that bit more fraught.

But when it comes to top work, spraying or front-end loaders then the Massey wins. It is lighter, cleverer, turns far tighter, and the cab has a far nicer interior for a day’s work.