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:D

Colin Chapman would have a different view i'm sure!

I think the engine and drivetrain resulted in the weight, rather than a weight decided from the start. That would be an odd way to design a car!
 

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If I may comment:

I think his central point is that the effectiveness of the design, both in terms of measurable performance metrics and user experience, derives from the interaction of car and road at the contact patches, and so the design is built, literally, ground-up.

On the point about weight and 1700kg being the right mass, solving for certain other parameters, eg 20 inch wheels, this is where I am not so clear.

Physics tells us that the tire frictional force is the byproduct of a normal reaction to the force (mass) acting down through the tire and whilst (putting in more intuitively) it is true that for any given tire, a certain degree of elastic deformation of the sidewall/tread is optimal in developing grip, isn't it the case that the centripetal force that resolves the attempted continuous linear constant-speed path of the vehicle mass grows proportionally with car mass (ie f = ma in angular units) and so isn't there a case for making tire choice and vehicle mass integral to the overall decision?

How about finding an overall solution to the problem that results in less mass and therefore less work for the tire to do in keeping the show on the road?

F1 cars (600kg) have to have low tire pressures to generate the right operating temperatures in the tires and must, as a result, have high profile tires with significant sidewall compliance. Here is an example of a system in which all parts have been designed together to deliver a result where the start point is 600kg, max/min dimensions fixed, certain other restrictions.

Perhaps he is saying, "if our premise is 4 seats, appropriate safety levels, good equipment levels, big wheels.... (lots of intermediate deductive logic left out). ...then 1700Kg is the best answer for the mass element of an overall integral solution"?
 

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I agree, I think he might be saying that 1700-ish kg was the best target they could aim for given the equipment specified and the target price.

They could easily have made the lighter, which for performance is indisputably desirable. However they could only have done this either be reducing the equipment level, or by using more expensive exotic materials which would impact the price.
 

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Sounds like sales BS to my uneducated mind, however seeing the stats and achievements of the GTR as well as first hand experience it truly has reinvented the automobile, so maybe 20" wheel package with 1700kg weight and 485bhp is "very important" to defying physics!
 

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has anyone tried to go the ligter R35 way as the only mod ?


Just to know if it is really important if the car made 100kgs less ....


i mean if it is a 2s on the ring, i couldn't care less.
 

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NISSAN GT-R press information...
press kit

goto mechanism and then start at package and go from there. it also talks about its low center of gravity where most of the weight is planted also helping.

here are some images...




you may also want to look here:
NISSAN GT-R Technical Review Vol.1 | R35GTR Special | NISSAN GT-R Web Magazine GTR-WORLD.net
it shows how ridgid and stiff the chassis is, and why it is the way it is. yes its heavy but because of its design it lacks the need of a huge cage system to get the same performance.
 

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NISSAN GT-R press information...
press kit

goto mechanism and then start at package and go from there. it also talks about its low center of gravity where most of the weight is planted also helping.

here are some images...




you may also want to look here:
NISSAN GT-R Technical Review Vol.1 | R35GTR Special | NISSAN GT-R Web Magazine GTR-WORLD.net
it shows how ridgid and stiff the chassis is, and why it is the way it is. yes its heavy but because of its design it lacks the need of a huge cage system to get the same performance.





he is very right tho. also best motoring also said it needed the weight for better control. lighter is ultimately better but right now the car standard is very balanced. if the car was lighter it wouldnt be able to corner as fast as it could and utilizing all the power to the ground (from its DCT) it would be purely unsafe for a road going street legal car.

however we have seen many cars from stillen, goto racing and various cars in Australia which have lowered massive weight... but they also balance it out with suspension, roll cage, in some case's tires and various other methods.
 

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he also mentions rain and snow and how importaint it is to be heavy enough for those conditions. AWD is not going to work by itself, it needs some help in those conditions. and with that much power and AWD, if its too light it wont perform safely as an everyday car on the street.
 

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Sorry, marketing BS imho. Within reason there's no substitute for lightness. All very well having weight to press the car down in a straight line, but at corners that same mass will try and pull the car off the road. Weight isn't aero downforce; downforce has no momentum...

Makes me sad that these days lots of effort needs to be made so that idiots don't throw it into the hedge too! :D
 

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Sorry, marketing BS imho. Within reason there's no substitute for lightness.
Totally agreed.

Perhaps my car will go faster when I add a passenger then.....

What will we see next, some Nismo lead weights to add to the car to make it faster still.

Obviously they got it wrong with the SpecV, where they stupidly cut 60kg from the car...... :)
 

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Totally agreed.

Perhaps my car will go faster when I add a passenger then.....

What will we see next, some Nismo lead weights to add to the car to make it faster still.

Obviously they got it wrong with the SpecV, where they stupidly cut 60kg from the car...... :)
Um no surely not. With Spec V they reduced seats by 50% and have delivered a weight reduction of 60kg at a cost of £50,000. Good idea? Mad idea?

I think the point re 1700kg making sense for the seats/size looks sensible.

Consider Ferrari 458 (1380KG, 2 seats, rear mid-engined) and McLaren MP4 12C (1300kg, 2 seats, rear mid-engined, which I have ordered for after the GTR!). Both weigh as little as is humanly possible controlling for the essential equipment and the Mc only gets to 1300kg via a carbon tub!

I think the increment of 400kg from the lightest possible 2 seats RME cars at three times the price is a pretty good benchmark. Another good benchmark is anything from Aston, Porsche, Maserati, Bentley etc...
 

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Yeah, but the weight wasn't being explained as a result of x or y, it was being described as an advantage...
 

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Okay. So if it lost, say, 300kg, the stabilty/traction control etc. would not work etc.?

My only gripe is the marketing BS I smelt :D
 
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