Thought I would see how much torque it takes to turn over the 5.3L being rebuilt.
It takes 4 kgM, roughly 40Nm or 30ftlb to overcome the friction in the bearings, rings and cams…
There are no accessories on the engine right now.
So at 800RPM you need 4.6HP to overcome friction.
At 6000RPM you need 34.5HP.
I will put an electric coolant pump on the engine.
If you add the alternator, power steering and mechanical pump the HP needed will be higher.
All this HP is needed just to turn over the engine and accessories before you deliver any HP to the transmission and rear wheels.
On top of this the efficiency of turning thermal energy in the fuel into mechanical energy is not brilliant.
One time I read the overall efficiency of a typical gas (petrol) engine is 25%. Diesel does better and modern engines will be better too.
Electric motors are so much more efficient turning battery energy into mechanical energy.
Naturally they loose nothing at idle, and maybe 5% running flat out. Converting 50Hz/60Hz power into battery energy has losses, and coal into electric power is a big loss too. Overall not so good unless you use sun power or wind power, then that is much better.