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shaneth
10-01-2007, 04:43 PM
Hey does anyone know what torque the standard Polo gti's are making at the wheels?

Glide_GTI
18-01-2007, 09:32 PM
I think it was 220nm, not sure if that was quoted at the wheels though

ausgolfer
18-01-2007, 09:45 PM
I don't know but a TDI 2L Golf puts out 320NM at the engine if that helps to give you an idea. So about 220NM at the engine for a Polo Gti sounds in the right area.

shaneth
18-01-2007, 09:53 PM
Yeah at the engine but from what i have been reading at the wheels it will be considerably higher. i will have to wait until i dyno it.

ausgolfer
18-01-2007, 09:59 PM
Umm after power and torque has gone through the transmission it is considerably less, usually around 25-30% less than at the engine figures for a rough guide.

shaneth
19-01-2007, 06:26 AM
In a front wheel drive car the power loss is actually only 15%. But as for torque (im not sure if this is correct so please tell me) but on another forum torqueing about talk :D a guy posted this,

The reason why the torque figure changes is because the gearbox is effectively a torque multiplier.

Its important to distinguish Power and Torque. Power is a measure of the total energy the engine is able to produce, whereas Torque is a measure of the turning force. Consider a massive boulder and you've got two iron bars to leverage it and get it moving. One bar is short the other long. We all know the long bar would have better leverage and be more likely to be able to move the boulder. The longer bar provides a greater torque multiplier for the same amount of exertion. A gearbox does similar things. Theoretically when the car is in 1st it would appear to have massive torque on a dyno.
Then after some research i found this. horsepower_torque (http://www.car-videos.net/articles/horsepower_torque.asp) . Let me know what everyone thinks.

Timbo
19-01-2007, 08:29 AM
I've seen this discussion before. As I recall, dynos actually measure torque, which is the ability of a power unit to maintain rotational effort for a given load. The computer attached to the dyno typically converts this into Hp or Kw.

The thing is, gearing enables a power unit to deliver different levels of torque, which is why it is important to settle on a particular gear when using a dyno.

It seems few people really understand torque (or power, for that matter ;) ). In terms of everyday driving, it was best explained to me thus:

Power is what gets you to the hill; torque is what gets you up the hill!

As a point comparison, my previous car was an RX-8, which has about 178Kw at the f/w (at 8500 rpm), and 220Nm torque @ 7200 rpm (and about 1350Kg). The Pog is 110Kw @5800rpm and 220Nm @ 1950 rpm (and 1200Kg)

On a flat road, at a constant 100kph, the Pog will initially out-accelerate the RX-8, both in top gear. That's the effect of the Pog's superior torque:weight ration. However, once the RX-8 drops back to 4th gear, it will out-accelerate the Pog, reflecting the RX-8's superior power:weight ratio.

...and a chipped Pog keeps the RX-8 honest right up to the first set of corners ;)