Maximum performance

The Bugatti Veyron makes 1000 hp, which is about 750 kW
The car weighs 4500 pounds.
Driving at top speed of about 250 mph uses 1.4 gallons (U.S.) per minute.
26.5 gallons of gasoline weighs about 165 pounds, and would let the car run for 12 minutes and go 50 miles.
The car has 10 radiators, a massive engine, intercoolers, turbos, exhaust system, gas tank. ( Because 70%+ of the energy is wasted as heat – there is 120 pounds of water coolant for the engine and cooling the exhaust. There are separate coolers and more coolant for all the other components ) The drivetrain probably weighs somewhere between 1500 and 2000 pounds.
A total drivetrain+fuel weight of 2000 pounds is a reasonable guess.
Since the Veyron gets 13mpg highway, those 26.5 gallons of gasoline would let it cruise 350 miles.

The White Zombie makes 500hp out of a motor that weighs 240 pounds ( but is only used in short bursts, it would need cooling ).
The Tesla Roadster makes 288hp ( 215 kW ) out of a 70 pound motor and an 80 pound controller.
I think it could be scaled up ( just have 4 of them ) to 1000hp in a total of 600 pounds. Since the current Roadster motors are air cooled – to sustain maximum performance liquid cooling will most likely be needed ( budget 200 pounds for that ) for a total of 800 pounds for the engine, controller and its cooling.

That leaves 1200 pounds for battery.
The current Tesla battery is 53 kWh in 900 pounds.
It can produce 250+ kW in short bursts ( approximately 5C – 5 times the energy capacity )
For comparison – the White Zombie battery is 22 kWh in around 400 pounds and produces 800kW in very short bursts.
If the Tesla battery were updated to todays bleeding edge cells it could make 70kWh in those 900 pounds. Scale it up to 1200 pounds and it would be 93kWh.

To make 750kW out of the motors at 80% efficiency you need 940kW of power from the battery. ( Note that because only 20% of our energy is wasted as heat – instead of 70% in the ICE car, the total cooling system we need for the drivetrain components is almost 4x smaller than in the Bugatti )
A battery of 188 kWh that can produce 940kW ( I picked 188kW to make 5×188=940 ) would only be a factor of 2 better in energy density than what we have today. This battery would allow for 750 mile cruising ( ridiculously more than anyone needs, and more than double the Bugatti ) and allow maximum performance 250 mph runs for about the same time and range as the Bugatti.
This is all napkin-back calculating at its worst, but here is a huge one in favor of the EV that I wont factor because I dont know how. Since we need about 4x less cooling, thats 4x less air to flow over radiators, and 4x less drag from that. That means that the EV should need much less horsepower to go the same speed, and we could reduce all the numbers for the power we actually need…

Of course once you have a 188kWh 1200 pound battery that can produce 940kW, you can make a pretty awesome car out of a 100kWh 650 pound battery that gives you 550hp and 400+ mile range. The instant torque of the EV will make it immediately superior to any ICE car of similar horsepower specs. It would also probably be superior to the Bugatti in acceleration up to 150 mph.

What is the point of all this?
Energy density in batteries is improving at about 8% per year.
I think that when it doubles from where it is now there will be no high performance arena that an ICE car will be compelling competition with an EV.

If we can sustain the 8% density improvement, then energy density will have made the magic doubling in 9 years.
To make ICE cars obsolete for general use, it all depends on the cost of these batteries.
But in the price is no object category of the top tier performance car like the 2 million dollar Bugatti – that battery improvement makes them obsolete in 9 years.

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