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Originally Posted by Meeni
Torque is a non-issue for a sport oriented car. Just make it scream. I don't see diesel being a better choice on this segment. Some overall win in endurance racing do not make for tthe complete story.
That, and the turbo petrol can also boast some impressive tq figures these days. I'n saying all that while lamenting the lack of diesel options for grocery getters, where it makes a lot of sense.
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You are wrong I'm affraid... torque is a fundamental aspect of a car's driving dynamics. What you are missing is the concept of TORQUE AT THE WHEELS.
High revving engined cars are able to get high torque at the wheels by means of very short gear ratios. Turbocharged diesel engines, on the other hand, can achieve the same result by means of an higher specific ENGINE TORQUE output readily available from very low rpm which allows the use of taller gear ratios.
Therefore, with a diesel engine not only you reduce the inevitable frictional losses associated with higher rotational speeds of the engine parts and transmission gears (the car's drivetrain) but also you get higher mileage for each rotation of the engine's crankshaft for the same engine rpm range, by virtue of taller gear ratios.
Moreover, with the increasingly popular 8-speed paddle-shift fast actuated automatic transmissions you are now able to keep much closer gear ratios in order to sustain higher acceleration throughout the gears. So, it's becoming normal for a less powerful diesel engine to allow a MUCH heavier car to match the 0-62 mph (0-100 km/h) acceleration time of a lighter and more powerful petrol engined one. I'll give you an example...
The 8-speed BMW M550d has a max. power of only 381hp and weighs practically 2 ton and yet is faster from 0 to 62 mph than a manual 420hp M3 V8 and basically matches the M3 V8 (7-speed) DCT acceleration time figure (4.7 sec against 4.6 sec). The M3 V8 DCT weight is significantly lower at 1650 kg!!! The difference is that while the M3 V8 DCT reaches 62mph from standstill in max. acceleration at 2nd gear hitting the redline, the triple-turbocharged M550d reaches that same speed in 3rd gear hitting its 5500 rpm redline for max. acceleration from standstill.
As for the M550d engine max. torque, it's unbelievable high at 546 lb-ft, whereas the M3 V8 only gives you 295 lb-ft.
'Grocery getters' you say... well, check this "Meeni" to go to the supermarket in the desert (also WTCC is not about endurance, you know?!)... this REALLY is EFFICIENT DYNAMICS:
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X-raid, winner of the Dakar Rally for the last two years with its near-indestructible Mini Countryman, has revealed its weapon for the 2014 race. Yes, it's another Countryman, and, as this teaser video proves, the big Mini will be just as tough to beat as its predecessors.
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Each Mini packs a 3.0-litre twin-turbo diesel engine producing 307bhp, 510lb ft of torque and a top speed of 110mph. There's a Sadev six-speed gearbox, an AP racing clutch, an Xtrac differential, AP ventilated discs measuring 320mm, and the whole thing weighs a rather gargantuan 1900kg
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