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Nice, but don't we already have tests for braking distances ? The 400m acceleration test has quite a few factors affecting it, apart from BHP & torque through the rev range - like gear ratios, final drive, & aero-drag.
If you have the braking distance for a car, say from 100Kmph to a full stop it should be possible to estimate quite fairly the braking distance at the end of the 400m sprint since energy is squared with speed. Of course this way does not include brake fade.
What is proposed, i.e. a 0-to-quarter-mile-to-0 run should throw up some interesting statistics nevertheless
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It is a good thought but it may not be a straightforward task measuring the braking effectiveness. There is only one way to accelerate but you can brake in different ways using foot brake, hand brake, engine brake or a combination of these. Some drag cars even use aerodynamic brakes to stop.
The braking distance would also depends on the surface conditions, tyre conditions, temperature of the brake pads etc.
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See, this is not just about braking. Its the ratio between acc and braking, if a family sedan can do 0-400m and then come to a halt in say 60mtrs (from whatever trap speed it can achieve), that would mean that it only needs 15% of the distance to stop from a 1/4 mile acc.
Now compare this to other performance cars and see what % of braking distance they need from the speeds they can achieve in a 1/4 mile.
As cars get faster n faster, its also important for manufacturers to make sure that the braking power is also increased in relation to the acc capabilities.
If a car is 4 times quicker than a normal sedan but only has 2 times the braking power, the sedan actually ends up having a more efficiant braking system, compared to its rate of acc.
Cars can use whatever braking tech they want, this test is only to see if the manufacturer has improved braking performance as well as they have done with the acc.
This is something like power to weight ratio, having only power or having only lightness doesn't count, you need a combination of both to make it work.
Shan2nu
Last edited by Shan2nu : 12th September 2009 at 12:48.
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