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autohabit
31-08-2006, 07:41 PM
When motor manufacturers quote torque figures (e.g. 400 Nm) how do the measure this?


Alan

Tony
31-08-2006, 07:49 PM
Not sure that I'm any the wiser!! (http://www.off-road.com/hummer/tech/power.html) :whistle: :lol:

T

IanHowell
31-08-2006, 08:31 PM
Originally posted by autohabit@Aug 31 2006, 08:41 PM
When motor manufacturers quote torque figures (e.g. 400 Nm) how do the measure this?


Alan
On a rolling road...

I am not sure if its true but urban myth says that when they were testing the Veyyron they broke the machine because it couldn't cope with the massive torque produced, litterally pulled it apart :o

Gary Kinghorn
01-09-2006, 09:10 AM
Originally posted by autohabit@Aug 31 2006, 08:41 PM
When motor manufacturers quote torque figures (e.g. 400 Nm) how do the measure this?


Alan
Not sure about a car engine but in other applications torque is measured using a brake device.
A simplified version of this would be to attach a torque wrench to the end of a motor. Keep upping the torque value on the wrench until the motor stalls out, that gives you your torque value.

Does that make sense?

Gary

evilowl
01-09-2006, 05:39 PM
Originally posted by IanHowell+Aug 31 2006, 08:31 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (IanHowell @ Aug 31 2006, 08:31 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-autohabit@Aug 31 2006, 08:41 PM
When motor manufacturers quote torque figures (e.g. 400 Nm) how do the measure this?


Alan
On a rolling road...

I am not sure if its true but urban myth says that when they were testing the Veyyron they broke the machine because it couldn&#39;t cope with the massive torque produced, litterally pulled it apart :o [/b][/quote]
Not quite. Manufacturers use engine dyno&#39;s not chassis dyno&#39;s. An engine dyno is where the engine and all ancilliarys are removed from the car and tested on a bench. This is a far more accurate way of measuring power.

Have a read through the technical articles on Puma Racing

http://www.pumaracing.co.uk/

pye21
02-09-2006, 12:12 AM
^^ Thats not exactly true, it is a more &#39;scientific&#39; (i.e. more parameters can be kept constant) approach to measureing the torque, but to get the true power figures you would need to have the exact same exhuast system, air filter and air flow over the engine (not possible in 99.9% of dynos), these can never be produced in a sealed enviroment. Neither way of measuring the torque/power is accurate but by using the same machine each time you can get an equivilant % of increase/decrease in performance.

Ian