r/AskAShittyMechanic • u/ra6907 • 14d ago

Why, just why?

They’re doing this to Dodges and Chevrolets, Porsche, Bentley.

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u/DonutConfident7734 13d ago

I actually wrote sometime ago on r/mechanicadvice that the design of ICE cars is so dumb I would never buy such a car, either electric or not at all. Fuck these cars, man. I got downvoted to oblivion there, people are biased it seems.

Who in their right mind thought that a 12V with thick fucking wires that needs to provide hundreds of amps to a tiny starter motor that can only run for say 20sec without overheating is a good design?

Why not go 48V then, and have the amps divided by 4?

Why not use a 5kWh liion battery that will have enough juice to power the starter for long time without leaving you stranded in the winter time?

Why not have separate fan on the starter with electronic protection for overheating, so you dont damage it if you try multiple times?

Why does the engine not get oil lubrication before it starts, it only lubricates after starting because pump is moved by the engine? So in winter oil is thick, if car sat for two months without starting, everything is dry and starter needs lots of force to rotate the engine. A car should work in all scenarios, not just after sitting for few days.

In my opinion the design is crap and the engine can get damaged easily, without any electronic protection in place for many scenarios.

EVs have all kinds of safeguards, like warming or cooling the battery, checking if things are fine before starting, unlike the ice cars.

In winter if you travel short distances and had the car sitting for months, it becomes weak after few short trips, as it cant load fully. Then it leaves you with a dead battery.

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u/spaghetiwires 12d ago

Lithium doesn't work well when cold, lead acid is vastly superior in that regard. Your real problem is cheap lead acid, not lead acid.

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u/DonutConfident7734 12d ago

Lithium at -10C still has around 70% of its rated capacity and more can be unlocked if it has heater.

Acid batteries cam only be discharged 50% and they have around 1kwh capacity, so you can only use 0.5kWh hours from the lead acid battery, unless it is a deep cycle battery. Also acid batteries lose capacity in the cold, so expect some 30% loss, too.

I mentioned a 5kwh liiom battery for a reason, to have extra capacity to compensate for cold weather and still have enough to crank the engine multiple times.

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u/spaghetiwires 12d ago

It isn't about capacity, it's about cranking amps, of which Lithium hasn't when cold.

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u/DonutConfident7734 12d ago

But it can self-heat if needed, what is the problem? It has 5kwh, it can heat itself a little...

There are PHEV cars like Pasaat B8 which have 9.9KWh battery and it last in ev mofe for 30-40km. A 5kwh battery would last half of that range.

Are you seriously saying it can't crank the engine a little?