Change your car with Carwow: Thanks to everyone who lent us cars for this video: - M60i: @wam_barn - M50d: How much quicker is petrol than diesel? Well to find out, we’ve got our hands on the most powerful petrol & diesel BMW X7s to see just how different they really are! So let’s check out the stats… Starting with the M50d, it’s packing a 3-litre straight-six diesel under the bonnet that can produce 400hp and 760Nm of torque. Power is sent to all four wheels via an 8-speed automatic gearbox, and it tips the scales at 2,460kg. If you’re looking to pick one of these up now, it’ll cost around £88,000. Then we have the X7 M60i. It’s housing an enormous 4.4-litre twin-turbo V8 under the bonnet, and this can put down 530hp and 750Nm. It’s a fair bit heavier than the M50d, coming in at 2,675kg, and it’s also a whole lot more expensive, costing around £130,000! So the petrol-powered X7 has more power, but will the weight difference prove decisive? There’s only one way to find out… LET’S RACE!