machin wrote:OK. One more try to explain the power and torque relationship:-
F=mA right?
Lets assume that your car has lots of grip (its not traction limited), and that aero resistance (force) is zero (e.g. low speeds). You'll just have to accept that we don't have any rolling resistance in this eaxmple. (EDIT: and that the drive train is 100% efficient -please bear with it).
The mass is fixed. In order to achieve a given level of acceleration we need to provide a motive Force at the tyre contact patch (the "F" in F=mA).
In order to determine the motive Force at the contact patch at a given speed you can use two methods:-
You take the engine torque at the engine speed necessary to achieve the road speed, you multiply it by the gear ratio and the final drive ratio. You multiply this result by the wheel radius -that gives you the motive force at the tyre contact patch.
OR
You Divide the power by the road speed. (F= Power/Road Speed)
The simple solution is the second method: you don't need to know the gear ratio, the engine speed, or the tyre size. You just need to know the power and the road speed.
Don't believe me?
OK:- 200BHP at 20mph means 16615N at the contact patch.
Now you have a go at getting more force at that contact patch at 20mph using a 200bhp engine and any gear ratio and wheel size you want. You won't be able to.
I'll give you some 200BHP torque values:-
200lbft @ 5250rpm or
400lbft @ 2625rpm or
100lbft @ 10500rpm.
Pick one of them and see if you can get more than 16615N at the contact patch at a road speed of 20mph. You won't be able to do it.
That's the first thing i did to get the wheel forces. Now concerning the power, that is only at a constant speed, that you can make a calculation like that.
What you say about gears being useless is aslo a error, and you never justified it with your graph.
I was going to ask you to clarify what is actually happening on your graph as well, what is this resistance exactly?
Aero ? and where does your car get such an unrealistic down-force from?
Secondly your graph avoids any implication of acceleration. Make your engine with only 200hp and do the graph again.
Your a tricky fellow.
Performance is grip limited because you forced it to be, to avoid the fact that one of your gears could easily well set the car within the grip boundary.
I am being very patient with you here. I will allow you to self destruct.
So please reduce engine power to 200hp, and then use a realistic downforce value. F1 cars do not produce as much down-force as people think. Most of the values are hypothetical with max df settings at 200mph.