This topic has moved on a bit ....
Here's a bit of comment I put together several years ago on this subject of torque and power. Kept it simple in the sense it uses two petrol NA engines, but in a way the variables get balanced out. Ignoring the dynamics of the chassis, in this instance we can just choose the engine we prefer, the more relaxed drive, or an engine we'd enjoy revving. Much the same as the diesel vs petrol choice we have.
Quote:
To illustrate that torque can’t be seen in isolation from power, or even power to weight ratios and gearing.
Take two petrol cars, with totally different power deliveries. Both E39 touring models, one a 540i 4.4-litre auto, the other an Alpina B10 3.2-litre manual. So we have lots of variables.
Back to back (group) tested by AutoCar.
0 – 60 mph: both cars, 6.2sec
0 - 100 mph: both cars, 15.9sec
30 - 70 through the gears: 540i 5.6sec; Alpina 5.5sec
Standing ¼ mile: both cars, 14.8sec/97mph
Alpina: 260bhp/5,900rpm; 243lb/ft @ 4,300rpm
540i: 286/5700rpm; 310lb/ft @ 3900rpm
Alpina: Power to weight; 160bhp/tonne
540i: Power to weight; 160bhp/tonne
Alpina: Top speed: 157mph unrestricted
540i: Top speed; 155mph limited. I’ve read the 540i model tested tops out at 157/158mph unrestricted.
Alpina: Gearing: 25.7mph per 1,000rpm. Max speed @ 6,000rpm; 5th gear.
540i: Gearing: 33.5mph per 1,000rpm. Max speed (limited) 5,780rpm; 4th gear.
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OK, the 330d and 335i won't fit that same model, but we still need the full rev range of each, to get maximum performance. But like our diesels, the 540i is the car that would feel 'stronger' in average day to day driving.
On a side note, big torque figures are fine in the diesels, but I wonder how far we can go before even the 'torque pulse' controls like the DPF, (now virtually the same technology included in the torque converter) will be either so heavy duty, or asking for even more advanced technology to give smoothness and longevity? We already have the torque values pushing the MT into the background, as the manual gearbox internals need to be so beefed up to carry the torque figures.
HighlandPete