[Pavlo]

Both cars are equal, only one is more equal than the other!

The answer is out there, lol!



Mycroft you crack me up!

paul

 

[Mycroft]

Indeed, that is true... you are getting there... at last...

The answer has been given, by me and is correct...

Humour, that's good, I like humour too...

 

[paul]

all well and good in theory, but in practical use totally flawed, otherwise Ferrari would be building their F2003 from lead no?

 

[Pavlo]

they might well do that if they could find a way to double the power too!

Mycroft,

So that "perfectly matched" statement doesn't include the traction circle then.

Paul

 

[Mycroft]

Yes, that is what I typed...

###
2 cars... 1 weighs 1 tonne the other 2 tonnes they both have equal power-to weight ratios and torque curve/gearing coincide exactly for each... they are perfectly matched... even down to the 'G' force each can generate in any given curve...

In a race the 2 tonne car will eat the 1 tonner... quite easily....
###

But that has nothing to do with transition...

Pavlo,
go away, read some books, come back and argue from a position of knowledge not just 'hope'...

'Rev' is closest... you are not in the picture as yet...

Do us all a favour, spend the £80 and read Milliken, then come back and agree with me rather than posting the pointless drivel you are subjecting us all to...

Last post on this for me... don't want to lose the will to live...

''I may leave, but my shadow may linger for a while''

 

[Pavlo]

I did have a detailed reply, but really can't be bothered.

Follow Mycroft's reasoning at your own risk.

Paul

 

[AlexJ]

I'm gonna regret this but;

2 cars... 1 weighs 1 tonne the other 2 tonnes they both have equal power-to weight ratios and torque curve/gearing coincide exactly for each... they are perfectly matched... even down to the 'G' force each can generate in any given curve...

the heavy one just sounds like a better car; twice the power with same ability to go round corners ( g's ) and later on i think we've talked about giving it the same ability to stop , we've almost completely counteracted all the ill effects of being heavy.

infact the only way you could improve this heavy car it is by making it lighter!

 

[Howsie]

I've enjoyed this thread!

... a ton of feathers or a ton of lead

 

[Mycroft]

I'm only posting 'cos Howsies' here and he makes me laugh! [so you haven't seen me roight!]

I'll have the lead... easier handling characteristics...

[bloody feathers get everywhere!!]

 

[Pavlo]

Re: Mass of car, cornering and braking

The heavy car is great, but there comes a point where the increase in grip can't match the increase in weight an it's associated increases in cornering forces, then you're screwed.

There also comes a point where you need to make the pair of tyres wider than the whole car to recover the friction lost due to excessive weight. Eg, a 10 ton car 6foot wide would in (very simple) terms need a 10 foot wide combined contact patch to compete with a 1 ton car that had a 1foot wide combine contact patch. Then there's tyre scrub issue on the corners, drag of wheels, just the plain stupidity of it etc.

The current trend in hill climbing is for lightweight cars. Having moved away from the big v8 engined cars to much lighter cars with bike engines or highly tuned 2-3l v6 engines and the like. They obviously need to read Doug and Bill Milliken when they can take a break from winning.

Paul

 

[NotoriousREV]

I think Mycroft is trying to lead us down the garden path of better weight transfer = better traction.

However, given the choice of Bentley Continental or Lotus Elise as my trackday car, I think Norfolk's finest would get the nod over Crewe's effort.

 

[Mungo]

What is Mycroft's point?

A better car is faster?
As has been stated, if you get rid of all of the things that potentially slow down a heavier car, then it will be faster than the so-called "equivalent" lighter car. And this is supposed to be a revelation? Strange how every competition car designer is reducing weight at every opportunity. How little do they know ...

 

[Simonh]

You are almost there Rev, but now, if you can, put in the cornering G force at 1 'G' to both... you may have to increase the tyres to 265s' to get equal cornering 'capture' speeds... and the bigger car eats the smaller one...

Because the heavy car will have a greater 'over burden' of power during any incremental speed it will almost always accelerate quicker for the same PtW ratio...

To corner a bigger car at 1G will mean that it will have huge reserves when in transition to the straight [I did mention this earlier] something like 80% greater adhesion in that transition...

For the heavier car to be slower in any corner would mean that the 'G' forces cannot be equal...

You must also ensure that the 2 tonne car can brake equally quickly, that means the singular factorial number must be upped to compensate... both cars must be able to generate equal 'G' in the braking too... do all of that and the 2 tonne car positively swamps the lightweight...

###
2 cars... 1 weighs 1 tonne the other 2 tonnes they both have equal power-to weight ratios and torque curve/gearing coincide exactly for each... they are perfectly matched... even down to the 'G' force each can generate in any given curve...

In a race the 2 tonne car will eat the 1 tonner... quite easily....
###

So in essence what you are saying is in a 180 degree turn with both cars generating the same lateral g (but not exceeding either cars level of traction) the 2 tonne car is using less of the power availble to it and can therefore acelerate away from the corner quicker?

Simon

 

[LSR]

To end the matter, a race around a track between a Lotus Elise and Bentley of some sort ended in the conclusion that the Elise ate the Bentley on the corners (that is what actually happened).

As for the straights, I don't recall what happened.

Also, a heavier car will take a lot longer to brake and will fall behind in cornering.

I think the Pyshics (sp?) lessons may be paying off for once.

 

[Mycroft]

However, given the choice of Bentley Continental or Lotus Elise as my trackday car, I think Norfolk's finest would get the nod over Crewe's effort.

To end the matter, a race around a track between a Lotus Elise and Bentley of some sort ended in the conclusion that the Elise ate the Bentley on the corners (that is what actually happened).

That is not the point of either the original question or my reply... ignore 'Elise vs Bentley' etc... that is not what is in question here... so both quotes are equally valueless.

----------

Strange how every competition car designer is reducing weight at every opportunity. How little do they know

No, not strange at all... he has rules to abide by and is also not building 'equal' cars, add to the saving of fuel... the list is endless... the question was... is there any advantage that a heavy car has over a light one... and given equal PTW ratio and equal Cornering powers... ie able to turn a whole circe at a given 'G' and Simon is again getting closer....

 

[LSR]

the question was... is there any advantage that a heavy car has over a light one... and given equal PTW ratio and equal Cornering powers... ie able to turn a whole circe at a given 'G' and Simon is again getting closer....

I can think of a lot of disadvantages for a heavy car, but I can see how it can do a 360 degrees circle at any given "g", due to lateral g's etc.

Mycroft,

Why did you get banned from scoobynet? I haven't seen any of your sure-to-be controversial posts over there. I should have asked this in my last post as I can't weight, sorry wait (pun) for the answer.

 

[SDB]

Hello all

As I understand it the question was whether a heavier car corners and brakes in a more performant way than a lighter car.

Whilst there is indeed a loophole in Mycrofts original reply that makes him correct in what he says. The loophole assumes an impossible and unrealisticly far fetch (even for the purpose of this
thread) scenario.

In answer to the actual question of this thread (keeping within the spirit of the information was actually requested), and without deliberately attempting to confuse people...

All other things being equal, a lighter car will (in almost all circumstances) be able to corner and brake more performantly than a heavier car.

It is possible to come up with very specific fantastic situations where this will not be the case, but I don't think the thread starter is after that.

Now...

Mycroft...
you wrote "he has rules to abide by " in response to a question of why do motorsport teams attempt to remove weight from their competition cars.

In all except the very unusual of circumstances, the rules regarding weight in motorsport are minimum weights, not maximums.

Are you suggesting that the manufacturers of race cars would rather make their cars heavier than the competition?

All the best

Simon

 

[LSR]

Weight related regs are different depending on the actual motorsport event - whether WRC, F1, BTCC etc. It is sometimes a range from the minimum to the maximum weight.

If a heavier car is better than a lighter car, then I should tell Honda this to bear in mind with their NSX programme. Maybe they should make their car heavier to beat the competition, and remember relative to the market, NSX is lagging in [straight line] power. NSX is light and is competent on track. I should also tell Radical, Westfield etc, all of who make track-orientated cars, to make their cars heavier, and remember, their cars are not 500bhp, their 100bhp/ibs ft torque, and with light materials, giving them a good PTW ratio. So if they make their cars heavier, they will be crap.

Heavier car:

slower turn in
longer braking distances (excluding thinking distance)
requires more power = more weight, if bigger displacement is used (f/i is the solution to this).

A lighter car is the opposite.

 

[Mycroft]

Mycroft,

Why did you get banned from scoobynet? I haven't seen any of your sure-to-be controversial posts over there. I should have asked this in my last post as I can't weight, sorry wait (pun) for the answer.

You could ask the chap who posted immediately after you [by PM preferably] as I can hazard a guess that 'SDB'... does not mean Simone De Beauvoir but may just mean Simon De Banke ... Webmaster of the now [if i may say so] rather duller, less exciting Scooby-net... he too, it appears, like so many over there is missing me...

As I understand it the question was whether a heavier car corners and brakes in a more performant way than a lighter car.

Yep...

Whilst there is indeed a loophole in Mycrofts original reply that makes him correct in what he says.

It is not a loophole... it is merely an example...

In answer to the actual question of this thread (keeping within the spirit of the information was actually requested), and without deliberately attempting to confuse people...

All other things being equal, a lighter car will (in almost all circumstances) be able to corner and brake more performantly than a heavier car.

There is the rub... ''all OTHER thing being equal''... I contend that lightness just makes a difficult task easier... in simple terms getting a 1 tonne car to corner at 1 g is very much easier than to make the 2 tonne car do the same trick... but if you manage it then the heavy car will beat the light one.

Mycroft...
you wrote "he has rules to abide by " in response to a question of why do motorsport teams attempt to remove weight from their competition cars.

In all except the very unusual of circumstances, the rules regarding weight in motorsport are minimum weights, not maximums.

Are you suggesting that the manufacturers of race cars would rather make their cars heavier than the competition?

I am not sure of your point here... none but a fool would construe that the objective in competition was to make a vehicle heavier than the rules allow... that is why I prefaced my statement with 'No, not strange at all'... it was not a statement advocating that Motorsport cars should be heavier... but in subtle ways they do... much of the gains found in a weight class are found by moving the weight around... much as Pilots will trim their craft by moving fuel around designers can gain from circuit to circuit by doing the same.

Perhaps you could clarify your thinking...

 

[LSR]

Did scoobynet ban your IP? Do you have adsl, you might have a dynamic IP. If they ban your IP, you can't use scoobynet from your machine. Sorry to hijack the thread, enthusiasts.