0-100 Km/h Times Are Useless, So Stop Asking For Them

[Big Rizza]

Hey all,

There seems to be a lot of people who seem to be using the 0-100km/h time as a bench mark for vehicle performance. However, in my experience the 0-100km/h time is not a great reflection. Why is that? Many of the real world traffic light grand prix events are from rest (0km/h) to the speed limit, or just over it (so about 100km/h), so surely this would be the definitive measure of a cars on street performance? Not really, no. I will use an example to illustrate my point.

Three cars line up at the traffic lights. All three cars have an identical 0-100km/h time. For simplicity, let's make it 10 seconds. The speed limit of this road is 100km/h, so it will be a race to the limit. Nothing illegal here

Car number one is a concept vehicle (why it's at the lights I don't know...). An electric vehicle. It doesn't make much power (in fact the top speed is only 100km/h), but it is ultra light, and has 4 in-wheel electric motors giving full torque from 0 rpm, meaning it can charge of the line hard. Car number two is a regular family car. The long geared automatic with big six cylinder power means that acceleration is fairly constant throughout the rev range. The final car has a big turbo, front wheel drive, and manual gearbox. This makes it tricky to get off the line, but once it's hooked up and the turbo spooled, the acceleration is very good.

The image below shows a representation of these three cars' acceleration curves. As you can see, all three will hit 100km/h at the exact same moment.

(for those who care, the electric car's speed was modelled by a quadratic equation speed=-(time-10)^2+100, the family car by a linear equation speed=10xtime, and the turbo by another quadratic equation speed=time^2)

So it's a race to 100km/h, and all three cars have an identical 0-100km/h time, so it should be a pretty close race, right?

WRONG!

The hard launching electric car gets the jump from the start, and wins by a full 45m over the family car, and a whopping 90m over the turbo car - that's about 18 car lengths!!!!

(For those who care, distances were obtained by integrating the speed equations stated earlier. If I made any errors then they were deliberate and hence I don't care - don't bother pointing them out, the electric car would still win )

This is obviously an extreme case, but I think it illustrates my point nicely. 0-100km/h times are stupid.

Edited June 15, 2006 by Big Rizza

[sewid]

I see.

[dangerous_daveo]

Thats on paper tho...

[**JaR**]

lol.

down with 0-100 times.

[ferni]

So basically you're saying distance covered in x amount of seconds is more important than 0-100 times...... say, like a 1/4 mile race?

You're right, but you could put money to say that a car that does 0-100 quicker than another cars 0-100 will also cover more distance, hence beat it 9 times out of 10.

In general a car that is quicker over the quater mile usually has a quicker 0-100 as well...................

[2rismo]

Electric cars are gay and the people that buy them don't care about performance anyway.

Adrian

[THE_350GT]

hahah Exactly I was thinking it you said it 2rismo. Spot on

Edited June 15, 2006 by the97skyline

[**JaR**]

Electric cars are gay and the people that buy them don't care about performance anyway.

werd

[JCMarshall_Law]

0 - 100km/h is still a pretty good measure of how "fun" a car is to drive, but I see what your getrting at.

10/10 for the effort

[CEF11E]

Big Rizza,

Props for such a well thought out post. you have much more spare time than me . That is really something to think about.

I hope I don't get beaten by a ful sik electric car.

[TurboX]

OK.....so based on your maths, what would the actual quarter mile ET and speed be for all cars?

[tim_08]

Maybe 100 - 200 km/h would be better times to gauge?

[mad082]

i was sitting there thinking your maths was screw up and they would all be the same... until i thought some more. a slightly sideways look at it is to look at quarter mile times and speeds. a mate of mine had a turbo exa that ran a 13.1 at 91mph, while his borther had a natro r31 that ran a 14.0 at 97mph. the exa would get of the line great, but didn't have the puff at high speed to keep pulling, whereas the skyline was hard to launch but had the balls up top to get the speed. so their 0 to 91mph time could've been the same, but the skyline would've done it in less distance.

a better indication of power is rolling starts, like 40 to 80, or 40 to 100. 0 to 100 is too dependant on traction. thats why wrx's have such low numbers, but in rolling starts they get beaten by rwd cars.

[Johnny Cash]

I think mention also needs to be made of 0-100 and 400m times for 4WD cars (e.g. GT-R's and WRX's). These rely on redline launches that not only cause serious damage to the gearbox, but are unlikely to occur in everyday drag racing.

I think a more appropriate 0-100 or 400m time would have to include a normal RPM point at which the clutch is released. This would go some length to explaining why an RZ Supra is so much quicker than a GT-R, although they both manage 13 second quarters.

And while we're on the topic of performance figures, I hate hp and kw readouts more than anything else - worse yet because people put so much stock into them. But that's a topic for another post.

[nissky]

So what time will my car do 0-100metres?

I dont have an front mount yet, also what will it do after i install a bov valve?

Can you also tell me how much boost is safe, if i only do 100 metres?

Any help would be appreciated, i tried a search but there were too many answers to my questions.

So i couldnt find any of the right answers i wanted to hear.

Edited June 15, 2006 by nissky

[Big Rizza]

OK.....so based on your maths, what would the actual quarter mile ET and speed be for all cars?

I chose those formulas with the 0-100km/h sprint in mind, and to extend them outside that will make them less representitive of a real world situation - they are simply too primitive to be extrapolated and still reflect real world situations. Particularly the turbo car, which by the formula will keep on accelerating faster and faster at a rediculous pace, but for the fun of it I will do it anyways

Due to the electric car reaching max speed at 100km/h, the after 10 seconds the family car will start closing the gap. Similarly, after 10 seconds, the faster acceleration of the turbo car at high speed means it will start running down both the family car and the electric car.

At the 15.0 second mark, the turbo car will catch the family car.

At the 15.4 second mark, the turbo car will catch the electric car.

At the 15.8 second mark, the family car will catch the electric car.

The turbo car runs a 16.3 at 265.69km/h (see what I mean about unreallistic )

The family car runs a 17.0 at 170km/h

The electric car runs a 17.7 at 100km/h

Whilst the 0-100km/h was a reallistic enough to show what could happen in the real world, this quarter mile situation is unlikely.

Even more unlikely is the turbo's standing kilometer - 22.1 seconds at 490 km/h.

EDIT: Oh, and here is the speed graph for the vehicles

And the turbo car does 0-1000km/h in 37.1 seconds, and is accelerating at over 60 g's by that point .

Edited June 15, 2006 by Big Rizza

[Wink]

Forget all this... 100-0kmh shows who's really hardcore - bet not many here have done a 'stand on pedal' full stop from 100km/h.

[mad082]

the record for 0-100mph-0 is pretty impressive. can't remember what it is, but i know it was held by a ford rs2000 for a little bit. i think it was a mix of time and distance.

[kralster]

Electric cars aren't gay. Have you seen that new Lexus forget what model it is, but's a big v8 with electric engine as well and it goes so damn hard and quite good on fuel for a big v8. They look awesom as well.

I'll try and dig up a website on it.

[Big Rizza]

Electric cars aren't gay. Have you seen that new Lexus forget what model it is, but's a big v8 with electric engine as well and it goes so damn hard and quite good on fuel for a big v8. They look awesom as well.

I'll try and dig up a website on it.

No V8 for the Lexus GS hybrid. It's a V6 with the power of a V8 and the economy of a 4cyl. Apparently.

Dunno if that was what you were referring to... There will probably be a V8 hybrid in the new Lexus LS, but that's not here yet.

Edited June 15, 2006 by Big Rizza