The e39 M5 is one of the greatest all around cars I’ve driven. It handles well, it pulls hard, its luxurious (by 2003 standards), and its spacious and comfortable. It’s such a well balanced car. The sound of ITBs on a V8 is orgasmic. There is a reason it is still frequently brought up as a benchmark in automotive…

Which part do you disagree with?

I agree. To your point on 2 and 3, those vehicles achieve traction through means other than weight. Wider tires, different rubber compounds. Traction on EVs is largely derived from weight. EVs tend to have narrow tires with harder compounds to reduce rolling resistance to increase range. 

Holler next time you visit, I live really close to them. Last time I tried to stop by they said they weren’t open to the public due to Covid. Is that still the case? 

So as you increase weight, force available from friction increases, but this is directly offset by the increase in mass you have to accelerate.

Which part do you disagree with?

Deceleration is often limited by traction, but isn’t always. sometimes there is sufficient traction but not sufficient braking power. 

I agree with that. I’m not sure what you’re trying to get at. 

You don’t seem to understand the point I’m making as evident by the videos you posted. I’m not watching 6 videos about power to weight. I understand power to weight. That doesn’t really have anything to do with that I’m talking about. I’m talking about traction.

If you have to resort to personal attacks, it really says something about your inability to formulate a compelling argument. That aside, if you can’t grasp that cars need traction to accelerate, there isn’t much more for us to discuss. 

You can’t substitute tractive force for force in the A=F/M equation. Valiant effort though. If Acceleration was only dependent on coefficient of friction and gravity, there would be no need for any additional force to move an object. Any object placed against another object would just start accelerating…

Imagine a how quickly a helium balloon would accelerate if it was sitting in the air spinning at 5000rpm on a horizontal axis. Mass (or a mass substitute, such as downforce caused by aerodynamics) is absolutely necessary for acceleration. Without it, there is no traction. Without traction, there is no forward force.…

Yes, weight could contribute to faster stopping as well if the limiting factor was traction instead of inertia. If tires are breaking traction, weight could improve traction, but would also carry additional inertia that would then have to be overcome. 

Substantially more than 10-20mm would be needed to apply instant torque without the weight.  It would need an impractically wide tire, or a tire of a compound that would wear too fast. Either of those would have a heavy impact on the range of the EV. 

I’m happy to continue discussing this until all questions are answered. 

Right, that’s true. They wouldn’t have traction to apply their power without their weight. 

Right. I didn’t say anything to the contrary.

Yes, there are many factors in achieving acceleration. I’m glad we are in agreement. 

All you need is adequate friction such that the torque doesn’t induce wheel slip

I’m not sure what part you don’t understand. Cars need traction to apply their power to the ground. EVs are able to achieve traction on otherwise mediocre tires because they are heavy. Mass is an enormous part of traction. Without the weight, the instant torque of EVs wouldn’t be able to be applied and they wouldn’t…