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Old 26th July 2003, 11:35 AM   #101 (permalink)
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Old 26th July 2003, 12:28 PM   #102 (permalink)
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It get's better and better

Thanks goodness, I thought I would lose interest. This is BRILLIANT stuff!

I'm not going to quote every part of your previous post as it would simply continue to drag out a pointless line of q&a, so I'll stick with a select few of your jems..

Quote:
the example given, to endlessly repeat myself, was chosen to in order to get the debate closer to the answer on the idealised weight/cornering performance.
This was not the question. The question was whether a heavier car increased cornering performance. and in-fact ---

-- Interlude --

For the benefit of anyone who's interested...
I realise I haven't touched on the question about wings making the car seem heavier (apologies if this has been answered already)...

Agreed, this seems like a paradox. The difference is... the wings create downforce, rather than actual weight. This force does not have to be accelerated (although the drag created does, but that's not relevant to the question of how it affects grip), where as weight does. As acceleration is instigated by the tyres, and this acceleration happens in all directions (including "accelerating", braking, and cornering) any actual mass you add to the car increases the ammount of acceration required.

Downforce does not add mass, but does add load to the contact patches, so therefore increases grip.

-- Back to the main feature --

Quote:
Now, forgive me, but isn't that the sort of thought provoking question that when outlined to many here has more 'value' to this forum than your dreary and constant re-iteration of your own tripe?
Something along those lines would have been fabulous. Why did you not chose to post something along those lines, rather than such a relentless stream of dribble?

In addition, I'm interested as to how you think wider tyres create more traction. Forgive me if you were merely stating that this kind of question could crop up.

Quote:
To remind you, this is the GTR forum, we (as yet) do not have a Muppet Arena for you.
Pure brilliance, your command of discussion and reason must make you very proud.

Regards

Simon
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Old 26th July 2003, 12:38 PM   #103 (permalink)
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Finished?
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Old 26th July 2003, 01:25 PM   #104 (permalink)
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Quote:
Finished?
Due to your inability to contruct, defend or support and argument, and your unwillingness to discuss the very subject you brought up, it seems, "yes I think I am".

I'll keep an eye on this thread, in-case you post anything of mild interest, or anybody posts a question I may be able to help on.

All the best

Simon
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Old 26th July 2003, 01:35 PM   #105 (permalink)
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... and just like the Boddingtons... he's not bitter!
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Old 26th July 2003, 03:12 PM   #106 (permalink)
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Old 26th July 2003, 07:45 PM   #107 (permalink)
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OK. I can see where you're going with this.

Correct me if I'm wrong, but you're saying that you can affectively add weight to a car in order to increase weight transfer and therefore provide more grip to the rear wheels?

Or possibly you're saying that if you don't have enough weight to utisile all of the available horse power, you will effectively be slower as you could have provided the tyres with enough load to utitlise more of that power?

Cheers

Simon
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Old 26th July 2003, 08:10 PM   #108 (permalink)
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Thumbs up

Welcome to the GTR, Simon.

We do not need to increase real weight, just increase transferred weight, maybe just doing things slightly differently to common practice will reap rewards.

What I am saying is that for the most part the GTR is well balanced as an off the shelf product, it works well, any mods have to be equally balanced if you wish the car to remain a fully rounded product.

I know that the majority of owners here use their car daily and many of them would like more of everything, better acceleration, better roadholding, the list is all encompassing.

To beat the original car as an even handed all rounder in all its' parameters takes some rather considered purchases.

Single goals are easier or rather they are more focused.
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Old 26th July 2003, 10:21 PM   #109 (permalink)
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OK..

It seems from your post that you do indeed mean the things I posted in my previous..

I'll explain where this falls down.

If you double the load on a tyre it produces less than double the grip.

So adding actual weight to the car, will mean that you have reduced the available grip as a proportion of the mass you need to accelerate. This effectively means the car will be slower.

Now, in your last post you have alluded to the real answer which is that you can use the weight in the car differently.

Raising the c/g will indeed create more weight transfer, which in straight line acceleration on a RWD car can indeed be a benefit (up to the point that the available power not longer excedes the ability of the tyres to transmit that power to the ground).

However, what that also does is increase load transfer under braking and cornering.

So by raising the c/g you have increased the potential acceleration of the car during the first few seconds of acceleration from very low speeds, and decreased the performance of both braking and cornering.

For sheer pure performance, the ideal would be a car that is able to place exactly the right balance of load around the tyres at all times.

Those exactly perfect balaces of load would be roughly as follows...

Straight Line Acceleration (RWD Car) : F/R 0/100
Straight Line Acceleration (FWD Car) : F/R 100/0
Straight Line Acceleration (4WD Car) : F/R 50/50
Straight Line Braking : F/R 50/50
Cornering : I/O 50/50

The above are impossible to create in the real world on a car that needs to complete a circuit.

You could create the top one quite easily (as they almost do with dragsters - hence the front popping off the ground).

None of the others are possible.

So chassis engineers need to look at the entire lap / functions of the car. As accelerating in a straight line from very low speeds represents a minute fraction of the circuits of the world, the c/g is kept as low as possible in order to create the minimum load transfer possible.

What the DO do next, is tune the damping in order to affect the speed at which the load transfer is transfered around the contact patches during transitional states. This obviously has nothing to do with the actual weight of a car.

All the best

Simon
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Old 26th July 2003, 10:45 PM   #110 (permalink)
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Old 26th July 2003, 10:55 PM   #111 (permalink)
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Got to go to bed now as we start leg 3 (Rally Deutschland) at 5:00am, but I'll be back tomorrow...

In answer to your previous post...

I completely agree with everything you have said (except a small point on the 4WD vs RWD which I'll expand on if you wish). I'm hoping therefore we have finally moved on from the idea that adding extra weight to a car will increase it's performance.

If you do have time this evening or in the morning, I would be very interested as to your methods of improving various aspects of the performance using the damping.

All the best

Simon
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Old 26th July 2003, 11:16 PM   #112 (permalink)
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Old 27th July 2003, 07:08 AM   #113 (permalink)
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Quote:
Originally posted by Mycroft
[B]That has never been my stand point, you will see the relevence as this thread progresses.
I was going to trawl through and dig out a load of quotes, but I don't have time, and I'm sure it would be futile.

Quote:
I am far from done with some of the simple things we can do that cost very little yet will imbue every car on this forum with a tangible benefit.
I look forward to hearing about them. Perhaps you would be good enough to get to the point and tell us about them.

Quote:
Before we mess with Dampers and settings/rates, we must delve into what part correct function plays in exploiting what adhesion we can muster.
Delve away.

Regards

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Old 27th July 2003, 09:44 AM   #114 (permalink)
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Old 27th July 2003, 10:00 AM   #115 (permalink)
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Quote:
Originally posted by SDB
Perhaps you would be good enough to get to the point and tell us about them.
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Old 27th July 2003, 10:43 AM   #116 (permalink)
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Old 27th July 2003, 11:26 AM   #117 (permalink)
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Mycroft

My original work (although I would never use such a self-important phrase) is constructed as I go along. Possibly this is because I can speak immediately from experience and understanding. I am able to do this whilst in the middle of a World Rally Championship round.

We are all different though, so I have no problem with that.

If you are telling me that your last post took you the 1 hour in between that and your previous I am surprised to say the least.

Anyway...

First of all. Be careful about suggesting huge performance gains from such a concept. The increase in performance is very slight indeed. For anyone who is still listening. Please do not go and actually change your springs purely for this benefit. By all means, select better springs when changing anyway, but not just for this.

Secondly.. I thought you were adamant that you were going to discuss things that cost very little before going on to other things? This, I seem to remember, is why you were unwilling to discuss the subject I was interested in.

I hope this post hasn't slipped in between two of yours

All the best

Simon
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Old 27th July 2003, 12:27 PM   #118 (permalink)
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Old 27th July 2003, 12:42 PM   #119 (permalink)
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LOL

If anyone else is actually reading this post (and therefore it is worth the time and interest) could they please post. Otherwise I think I will channel my spare time in a different direction

All the best

Simon
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Old 27th July 2003, 12:55 PM   #120 (permalink)
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