Viewing a single comment thread. View all comments

SatanLifeProTips t1_irjfaa1 wrote

Reply to comment by Zebritz92 in Germans ZEDU Car Is Most Environmentally Friendly Vehicle In The World by Educational_Sector98

Why bother with an extra induction braking system when you can build an electric car with 500hp? That gives you 500hp of braking as well as acceleration. A lot of people don’t realize that is a 2 way street on EV’s. The friction brakes are just a backup. And yes those can be enclosed oil bath type since they are used so infrequently.

1

Knut79 t1_irjh5v2 wrote

How does brake pads in an oil bath work at -20 to -30 and less celsius?

2

SatanLifeProTips t1_irjhk0h wrote

Same way your engine starts at -45. Pick the right oil.

Modern synthetic oils flow at extremely low temperatures just fine.

2

Knut79 t1_irji63y wrote

Except engines run extremely bad untill the motor gets warm, motor heaters should be used to reduce excessive wear on the engine during startup and warmup in winter, for diesels a webasto is a preferable solution as it doesn't need electricity, and also because diesel cars may not even start without warming up first.

1

SatanLifeProTips t1_irjl2qf wrote

‘Engines running poorly’ when cold is due to condensation of fuel on the cold cylinder walls. Vapour fuel burns, liquid fuel does not burn. That’s why the choke plate added extra fuel on a carb and why your fuel injection needs a coolant temperature sensor to do the same. Nothing to do with cold oil.

The oil flows just fine now. Modern oils have solved those flow problems. Especially synthetics.

3

Knut79 t1_irjlixg wrote

If only there was some way to look at the oil in winter and see that it has reduced viscosity as is closer to honey than motor oil...

I don't know... Maybe a stick that also could be used to measure oil level... Seems far fetched.

1

SatanLifeProTips t1_irjm1b4 wrote

Or just read the bottle or better yet the SAE engineering data? These are published numbers.

2

Knut79 t1_irjmazk wrote

Have you even checked a metering stick at -30?

1

SatanLifeProTips t1_irloeo5 wrote

Yes. I also use synthetic oils so that is a non issue. Read the cold weight if your oil. A 15w40is going to be thick. But then you get into a modern 0w40 and it’s super thin when cold. It’s not like gear oil with it’s ‘channel temperature’. And anyone out in the frozen nothing is buying the right oil.

A wet braking system would be using a super thin oil. Like ATF. You don’t want a film like engine oil. That’s what crank bearings use to not contact the metal underneath.

1

Zebritz92 t1_irjh3r2 wrote

I'm not sure what led to that decission, but in the end it's a concept vehicle. They mention how braking can affect tyre wear, depending on where they're located. Maybe that's the reason they included this breaking system.

Or maybe they just wanted to try out the technology?

1

SatanLifeProTips t1_irjhn0m wrote

The Germans were just excited to over engineer an entirely new system.

1