What is it?
The Land Rover Discovery Si4, a four-cylinder petrol variant of the seven-seat luxury SUV, has been added to the range at a useful time to capitalise on the continuing slump in popularity of diesel engines.
The question is: can this turbocharged 2.0-litre inline four with 296bhp and 295lb ft really be a match for the kind of oil-burning unit that is traditionally found under the bonnet of practical-but-posh workhorses such as the Solihull-built Discovery?
The engine, part of Jaguar Land Rover’s Ingenium ‘AJ200’ family constructed at the engine manufacturing centre in Wolverhampton, has previously been added to the line-ups of the Land Rover Discovery Sport, Range Rover Velar and Evoque.

On the Discovery Si4, it is mated to the eight-speed ZF automatic transmission and four-wheel drive system that are ubiquitous across the fifth-generation Discovery’s range, which you can read more about in our full road test here.
Our test car came in SE trim, one up from the entry-level S specification, but it was still as well appointed as you’d hope a £50,000 SUV might be. Kit highlights include a 10.0in touchscreen infotainment system, air suspension, heated front seats, LED headlights, a 250W, 10-speaker sound system and leather front seats.
Options on our test car were limited to privacy glass (£400), a rear-view camera (£375) and 360deg parking assist (£280). The latter two proved useful for backing the Discovery into dauntingly tight multi-storey parking bays.
What's it like?
More accomplished than it might appear on paper. The petrol unit does a fairly spirited job of pulling this two-tonne 4x4 on motorways, A-roads, B-roads and around town. At cruising speeds, engine noise is muted and, allied with the general hush present within the cabin, there’s a veneer of refinement you don’t get from diesel derivatives. In that respect, this new engine complements the 4x4’s laidback vibe rather well.
Land Rover claims 7.3sec for the 0-60mph sprint and there’s certainly decent enough urge from low in the rev range, although under load the unit seems to work harder to maintain your momentum than a more flexible diesel might. If you call on additional power, the eight-speed automatic transmission is kept quite busy shuffling up and down through its ratios.
Read about the Land Rover Discovery TD6 HSE on our test fleet
Fuel economy could suffer as a result. Our 179-mile test yielded an indicated average of 27.3mpg against Land Rover’s claim of 29.4mpg, but if you spend a lot of time enthusiastically using a Disco as nature intended – dragging a horse box, brimmed with people, bounding along country lanes – you’ll do well to see that.

Elsewhere, the Discovery’s trademark traits remain. Its four-wheel drive capability and the ability to raise the air suspension to ‘off-road’ mode, which is up to 75mm higher than the standard setting depending on vehicle speed, ensure our test car dealt with the worst that the recent snow blizzards could throw at it with consummate ease.
The Si4 comes in at about 20kg lighter than the SD4, thanks to the lighter engine – a useful saving, if not one that has a tangible impact on the driving experience. This is a tall, heavy, comfort-oriented vehicle, after all, not one that reacts to being hustled with any particularly relish.
Should I buy one?
Time was that the least powerful petrol variant in a model’s range would often represent the entry point, but that’s not always the case these days. This petrol derivative is £700 more expensive than the 237bhp 2.0-litre SD4, which is the equivalent diesel. The petrol is quicker – not that raw pace is likely to be a primary concern for most Discovery drivers – but delivers inferior fuel economy and emits more CO2 than the SD4. It also spews out less in the way of particulates.

If you’re buying a Discovery for its style, space and useful high-riding driving position but don’t intend to use it to its full capabilities or load it full to the gunwales, this version could suit your priorities.
However, if you’re one of those buyers who intend to work their Discovery hard, tow trailers, occasionally venture off road, regularly achieve high mileages and desire additional frugality, it’s hard to look past the diesel.
Land Rover Discovery Si4 SE
Tested Hampshire, UK; On sale Now; Price £52,995; Engine 4 cyls, 1997cc, turbocharged petrol; Power 296bhp at 5500rpm; Torque 295lb ft at 1500-4000rpm; Gearbox 8-spd automatic; Kerb weight 2162kg; 0-60mph 7.3sec; Top speed 125mph; Economy 29.4mpg; CO2, tax band 222g/km, 37%; Rivals Audi Q7, Volvo XC90 and BMW X5