no such thing as 'torque at the wheels', that is thrust, linear, not radial T = F cross r, thrust = T x gearing / tire radius)
obviously less losses and 'as delivered' thrust to the wheels
HP is a derived number
torque is a physical variable, a force, discussing anything but torque is pointless...no engineer uses HP in calculations for acceleration
it's like trying to determine current flow from KW-Hr without knowing the time duration...impossible
P = T x w (w = 2 Pi n, n = rev/sec engine speed)
in HP and lb ft: T = HP x 5252/rpm
5252 = 550 ft lb/sec x 60 sec/min / 2 Pi
take an F1 car
it spins at 18000 rpm (300 rev/sec)
there is a huge difference betwen 250 lb ft at 6000 rpm and at 18000 rpm
if you know the torque you know everything
if you know HP, you need the rpm
again, no magic, only physics
the GTR is exactly as fast (as I have shown, btw, gearing is factored in, and tire radius is ~ the same so can be ignored since thrust (lb force) = gear ratio x T/tire radius) as one who understands these things would 'expect', I prefer estimate or calculate
as shown above, it is physically impossible to double the HP and not double the torque for any given rpm, that is plain silly
adsgreen wrote:It's not much to do with the engine torque - torque at the wheels is all that counts and thats always better with bhp rather than torque.
Toruqe is largely irrelevant for performance driving - a car with more HP accross the power band for gearing will always be able to go faster than a car with less hp and more torque. Now I know power is a function of torque but massive torque doesn't mean fast.
Take an F1 car - nearly 800-900 bhp and less than 250 lb/ft torque but not what you'd call "slow". Similary, the classic problem with diesels is the large torque and coupled with low power through lack of ability to maintain the power at high revs. This means a longer gearing is required in order to achieve sensible road speeds and as such the all important torque at the wheels is reduced.
Finally, I've had race engines built for other cars using 1.8 rover K series units and once tuned and optimised had much less torque than a standard but double the bhp. With the same geabox the track car was significantly faster even though at no point did it have more torque than the standard one.
There's plenty of other 1.8 tone cars with the same power and torque (or) more than the GTR that are substantually slower.
99% of the performance of the GTR is down to:
1) a very slick DSG gearbox making gear shift times pretty much zero.
2) probably one of the most advanced launch control systems on a road car.
3) surprisingly good aero
My track car is virtually the same 0-60 as the GTR but in gear would noticably gain on it (I have traditional manual).
I'd agree that the car isn't great on the road but on track it doesn't feel half as bad. I guess this is the problem with all cars that spend too much dev time at the ring.
