Originally Posted by Little Nismo
Ok not a weightless but a very light car. The point was really asking is there a cross over point at which your vehicle is too light for the power and the selected wheel size?
Ie if the gtr weighed 1200kgs is that too light? What about 1000kgs? 900, 800.
Of course I don't deny that light can be good the lotus formula of 800-900kgs and 250hp makes for great track cars.
I'd be interested in whether you believe the weight has no advantage in snow ice wet at low speeds and on launch?
If I hear you right you are saying making a 4wd road gt car means that you will have to have 1800kgs or I'm guessing make it expensive (carbon fibre) and the rest of the specs are all to overcome that weight? You are saying there is no trade off for less weight in low downforce situations?
Yup that's certainly a possibility but why would they make up porkies about it? It seems a little pointless. Why not just say that the weight is a function of the car dimensions engine and 4wd drive and the power wheel size suspension etc are selected around this.
Which I guess is the point of this thread.
Is it that now engines with massive power and torque can be made so manufacturers look to make the most of this. But to have a 1200kgs car with 600hp is gomna be a handful in amateur hands in adverse conditions?
My position on this from a physics point of view is that reducing the weight would not affect the launch performance with a very big caveat.
The Co-efficient of friction is only valid until you break traction, at that point it is significantly reduced and is also highly variable. The problem with reducing weight to 1000kg and keeping power at say 600bhp is that its easier to break traction, although we could equally argue that dialing the power down to 10/18ths would keep the traction profile the same as the heavy 600bhp car. Same story with snow.
You make a good point with tyre sizing, we've got to remember here that when you corner or brake the weight shifts significantly towards front or rear, left or right and as such if you know the car is going to be 1800kg and 4wd you need to spec each tyre to be able to deal with a majority of the weight bearing down upon it. Making a lighter car would definately affect the tyre choice.