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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#31

Post by kingsuper20 »

specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

>So one would think that when EVs reach the same scale they will be significantly cheaper than ICE vehicles.

I expect that batteries are the only hangup, there's probably not that much magic left in an electric motor. Additional cost for regen brakes of course.

I agree on the amazing cheapness of it all if you stick with the common stuff. That, along with the low cost of flat panel TVs is a miracle of the modern age.

Re: Internal Combustion Engine

#32

Post by tmh88j »

specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

Nice! What engine did you build?

>The distance between a crank bearing or rod bearing is less than 2 thousandths on modern engines. A small amount of oil in that tiny space is all that keeps your engine from having metal on metal seizure.

The BMW S65 and S85 engines are prime examples of what happens when the wrong tolerances are chosen. I can't think of another engine family where rod bearings are considered a maintenance item.

Re: Internal Combustion Engine

#34

Post by piva00 »

kingsuper20 wrote: post #31
specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

>So one would think that when EVs reach the same scale they will be significantly cheaper than ICE vehicles. I expect that batteries are the only hangup, there's probably not that much magic left in an electric motor. Additional cost for regen brakes of course. I agree on the amazing cheapness of it all if you stick with the common stuff. That, along with the low cost of flat panel TVs is a miracle of the modern age.

> there's probably not that much magic left in an electric motor.

I believe this sentence has been said about many technologies in the past that definitely invalidated it. I'm more playing devil's advocate than trying to falsify you, likely for being burned sometimes reading or, worse, stating it, haha.

Re: Internal Combustion Engine

#35

Post by legulere »

Viker wrote: post #25
larsnystrom wrote: post #23

In a few decades the internal combustion engine will be to transportation what the typewriter is to typing today. It’s kind of mind boggling, but there is really no alternative if we want to stop increasing the CO2 concentration in our atmosphere.

Hmm... Hard to beat that energy density when the workload is large. Trucks, tractors, planes, ships. Sure consumer cars will be EV but ICEs are not going anywhere

Don’t forget to talk about rockets! Although there weight is more important than volume.

Re: Internal Combustion Engine

#36

Post by Syonyk »

kingsuper20 wrote: post #10

It's a lot scarier when you see things going under load at speed. Lots of wiggling, twisty magic, waves. Smokey Yunick (blessed be his name) used to make see-through timing covers, oil pans, valve covers + strobe light + some sort of oscilloscope setup to watch the craziness. I think I remember seeing the results for small block Chevrolet timing gears on sprint car engines as the teeth wiggled more and more with rpm.…

> Smokey Yunick

Oh, man. I'm not a huge NASCAR fan, but that guy. That guy. He was an absolute master of "But the rules didn't say I couldn't..." and probably is responsible for half the thickness of the modern rulebook on his own!

"What? The fuel tank capacity can't have an inflated basketball in it that springs a leak during the race, leaving us with more fuel capacity?"

"What? The fuel lines have to be a short path between the tank and engine? Now, look, nowhere in this here book does it say I can't stuff the frame rails with a couple hundred feet of spiraled fuel line. It gets an extra gallon or two in the car? Really? Huh..."

"Nowhere in the book does it say the bodywork has to actually match the size or positioning of the stock car the race car is based on. I can't help it if nobody else has totally redone the bodywork to improve aerodynamics... oh, OK, you're bringing cardboard templates next season, got it, that trick is done."

The guy was an absolute master of "creative advantages that weren't actually illegal at the time they were used."

Re: Internal Combustion Engine

#37

Post by kirse »

larsnystrom wrote: post #23

In a few decades the internal combustion engine will be to transportation what the typewriter is to typing today. It’s kind of mind boggling, but there is really no alternative if we want to stop increasing the CO2 concentration in our atmosphere.

Pure EVs will reach a fundamental peak percentage similar to any other car class... Hybrid powertrains are really where the next 20-30 years are headed for the bulk of vehicles. Automotive racing and supercars have demonstrated hybrids are the most effective setup for the past decade, and barring some major breakthrough in battery tech that will all trickle down into consumer cars over the next 0-20 years.

Re: Internal Combustion Engine

#38

Post by mfer »

specialp wrote: post #15

I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive. Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of in…

If people were willing to pay the higher cost for the same feature set, why would they well them for cheaper? Why not pocket the extra profit?

I don't like this line of thinking but I'm sure it's going to or already is happening.

Re: Internal Combustion Engine

#39

Post by adrianpike »

kingsuper20 wrote: post #10

It's a lot scarier when you see things going under load at speed. Lots of wiggling, twisty magic, waves. Smokey Yunick (blessed be his name) used to make see-through timing covers, oil pans, valve covers + strobe light + some sort of oscilloscope setup to watch the craziness. I think I remember seeing the results for small block Chevrolet timing gears on sprint car engines as the teeth wiggled more and more with rpm.…

We had a see through engine w/strobe system at the uni I studied vehicle engineering at, it was really really educational to be able to adjust ignition timing and fuel mixture and see how it would change the color & shape of the flame front.

Probably a ton easier to simulate it these days but at the time it was absolute magic and really helped me understand how to ear-tune an engine to at least good enough to get on a dyno.

Re: Internal Combustion Engine

#40

Post by whatever1 »

Viker wrote: post #25
larsnystrom wrote: post #23

In a few decades the internal combustion engine will be to transportation what the typewriter is to typing today. It’s kind of mind boggling, but there is really no alternative if we want to stop increasing the CO2 concentration in our atmosphere.

Hmm... Hard to beat that energy density when the workload is large. Trucks, tractors, planes, ships. Sure consumer cars will be EV but ICEs are not going anywhere

People have hard time grasping how much energy chemical bonds can hold. 15 gallons of gasoline store 500kWh of energy. That is 5 tesla model s worth of energy.

Efficiency plays role for our day to day car tasks, but when you have to deal with external forces or higher requirements of momentum, then you need more energy period. Towing, beating high-speed drag / waves, climbing high, cannot be addressed with smarter design. You need to be able to store somehow enough energy to deal with these external forces / additional required momentum

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