Land Rover Discovery 4 vs Range Rover Sport review

Sometimes, more technological attention needs to be paid when developing new versions of old-school stuff that worked.

Not surprisingly, the leading vehicles in the breaking ground stakes in this year’s 4X4OTY contest were the Discovery 4 and the Range Rover Sport.

Historically, Land Rover’s brands have introduced more 4X4 innovations than any other marque and this trend continues in the 2010 models.

The stand-out technological advance this year is the new 3.0-litre TDV6 engine that powers the Discovery 4 SE and the base-model Range Rover Sport. The sequential twin-turbocharging technology employed in this engine is a first for a 4X4 wagon.

Twin turbos are fairly common on V-engines &#151 LandCruiser 4.5-litre V8 and Land Rover’s TDV8 being two 4X4 installations &#151 but these are parallel fitments, in which each turbo is driven by one bank of cylinders. The 3.0L TDV6 has two turbos, but they’re connected switchably in series as well as parallel.

The primary, larger, variable geometry turbocharger boosts on its own when the engine is running at low revs.

From 2500rpm upwards the smaller fixed-geometry turbocharger is activated, initially pushing boosted air directly to the intake port of the larger turbocharger in a series operation to ensure smooth boost ramp up, before being redirected to the intercooler 0.3 seconds later, when the smaller turbocharger is fully operational.

At engine speeds above 2500rpm both turbos pressurise the intercooler in a parallel operation. When engine speed drops the small turbo shuts down.The result is seamless variable boost from a small turbo, with reduced pumping losses which is said to improve economy.

Outputs of 180kW and 600Nm aren’t far shy of the figures of the 3.6-litre V8 used in the Rangie Sport and the 4.5-litre V8 that powers the LandCruiser 200 Series. Topping all that off is an oil and filter service interval of 26,000km or 12 months.

Not content with engine innovation the two 2010 Land Rover vehicles also incorporate changes to their class-leading Terrain Response 4X4 drivelines: a new sand launch function that limits wheelspin when lifting off in soft sand; and automatic application of brake pressure below 5km/h in first and reverse gears in the Rock Crawl setting to reduce roll back or forward. Hill Descent Control incorporates gradient release to reduce initial acceleration on steep grades.

Trailer Stability Assist detects trailer sway and corrects the movement by limiting engine torque and applying selective vehicle wheel braking. Vehicles with the surround camera system option have helpful tow-hitch guidance bars on the screen image.

The V6 Rangie Sport can be optioned with Dynamic Response, which automatically adjusts air suspension pressures when cornering, to limit body roll. V8 models can also be specified with an Adaptive Dynamics system that automatically alters damper settings between soft and hard, depending on road, load and speed conditions.

The 2010 Prado Kakadu’s hefty 89 grand price tag promises much ground breaking technology, but the NG model is just a re-skin of its predecessor and that design limits what can be achieved. The Kakadu features list reads similarly to an up-spec Discovery’s, with the addition of the 200 Series’ CRAWL off-road control function and KDSS.

Like the Rangie Sport, the Prado Kakadu can be ordered with radar-controlled adaptive cruise control, but to do so means the buyer has to surrender CRAWL control, the electronically locking rear differential, one of the surround cameras and Multi-Terrain Select (Toyota’s version of Land Rover’s Terrain Response), effectively lowering its off-road credentials.

The Kakadu spec includes a forward-looking camera with direction bars indicating current wheel path &#151 a useful off-road driving aid for the inexperienced operator.

The GXL model gains some standard equipment advances over its predecessor, including an aircon-cooled centre console box, hill-start assistance, a rear view camera and parking sensors. Unfortunately, the Kakadu’s electronically lockable rear diff is not a GXL option.

Oddly, the rear power outlet in the new Prado is a 220-volt three-pin socket, not the usual 12-volt one. We have no idea why.

Speaking of odd, all the 4X4OTY contenders, bar last year’s winning Pajero GLS, were fitted with slightly different versions of the latest auto-motive craze &#151 keyless start and stop.

With this so-called smart start idea the car entry fob needs only to be in the car for the vehicle to be started, using a one-time fashionable start and stop button. Only a brain accustomed to turning off a computer by pressing the start button could have devised such a system.

What’s wrong with keyless start and stop? Let’s look at one scenario: your wife drops you off at the airport, kisses you goodbye and off you go on a business trip ... with the car fob in your pocket. She goes home and leaves the car open and running for five days, until it’s time to come and pick you up.

Wouldn’t happen? How about a garage with two vehicles, both of which have smart start: you and your partner start engines and leave home at the same time, but with the wrong fobs. Smart start is no such thing: it’s stupid start, and the sooner this fad vanishes forever, the better.

Oh, the inclusion of this feature also means the manual GXL Prado can’t do an off-road stall-recovery lift-off, because you need to depress the clutch before the engine will start. Dumb, eh?