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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#51

Post by [deleted] »

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.

[deleted]

Re: Internal Combustion Engine

#52

Post by benlivengood »

pram wrote: post #22
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…

I think automatic transmissions are more impressive looking than engines when they're open. They resemble EV motors too!

Automatic transmissions also have hydraulic logic gates in the valve body (implemented with check-balls and piston servos), even if they're also electronically controlled. Drag-racers will reprogram the valve body to change the shift order, have launch control, etc.

Re: Internal Combustion Engine

#53

Post by londons_explore »

piva00 wrote: post #34
kingsuper20 wrote: post #31

Earlier quoted context omitted.

>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.

There isn't much more efficiency to be gained in the electric motor world. Motors typically get 90% of theoretical efficiency, so any improvements there will be modest.

Substantial improvements in other metrics might be had, but they probably won't massively impact EV's (weight and costs of the motor are both a small part of the total for a car)

Re: Internal Combustion Engine

#54

Post by [deleted] »

jiofih wrote: post #27
Syonyk wrote: post #9

Earlier quoted context omitted.

I had no idea until I read your comment that you could click and drag the engine models! Insane!

The text immediately before the first image says “You can drag it around to see it from other angles”. Our attention spans are deteriorating quickly…

[deleted]

Re: Internal Combustion Engine

#55

Post by tmh88j »

specialp wrote: post #41
tmh88j wrote: post #32

Earlier quoted context omitted.

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 maint…

I built an LSX (Aftermarket GM) iron block engine (V8 LS) for a CTS V. I had to get some very precise tools (Have to measure to 10,000ths) or they were useless for bearing clearances and verifying cylinder diameters. My cylinders were 4.155 bore, and the bearing clearances were around 1.8 thousandths. Forged pistons, rods and crank. I had cracked a cylinder/piston on the original LSA. I did not trust anyone to do the…

>I had cracked a cylinder/piston on the original LSA. I did not trust anyone to do the work so I did a lot of research and did it all myself

I love working on cars so I totally get wanting to do that, but why didn't you trust someone else to do the work? There are probably more reputable LS builders across the US than any other engine family.

Re: Internal Combustion Engine

#56

Post by kingsuper20 »

londons_explore wrote: post #45
kingsuper20 wrote: post #31

Earlier quoted context omitted.

>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.

> Additional cost for regen brakes of course. Regen braking has no physical cost associated - it's pure software/firmware. The exact same hardware that is used to power the car forwards can be used for regen braking. It can be as simple as a single negative sign in the code to cause the phase to be 180 degrees out, current to flow backwards, torque to go the other way, and the battery to be charged instead of dischar…

Is that right? I didn't know that. I'd like to see a BOM on a regen braking as compared to a simple disk brake system.

One implication to software-only brakes is that it requires that that corner is a drive wheel. If that's the case, I suppose that anti-lock is simply firmware and a sensor.

note: I do see that Teslas have master cylinders, so they apparently are hydraulic braking systems.

Re: Internal Combustion Engine

#57

Post by jborichevskiy »

Syonyk wrote: post #36
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 pat…

> "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?"

Pardon my ignorance- what is the motivation for temporarily reducing the fuel capacity in this example? And why was it disallowed?

Re: Internal Combustion Engine

#58

Post by kingsuper20 »

mfer wrote: post #46
kingsuper20 wrote: post #31

Earlier quoted context omitted.

>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.

> I expect that batteries are the only hangup, Batteries are a huge hangup. For example, we don't know how to recycle them and they aren't good for dumps. And, used car batteries are expensive to replace and you get a lot fewer miles per charge out of older cars. Manufacturing of cars isn't great for the environment so we should want older cars to last. This model helps push people to more new cars faster.

No problemo. Just go to a big honkin' flywheel somewhere under the back seat.

Re: Internal Combustion Engine

#59

Post by dahfizz »

kingsuper20 wrote: post #56
londons_explore wrote: post #45

Earlier quoted context omitted.

> Additional cost for regen brakes of course. Regen braking has no physical cost associated - it's pure software/firmware. The exact same hardware that is used to power the car forwards can be used for regen braking. It can be as simple as a single negative sign in the code to cause the phase to be 180 degrees out, current to flow backwards, torque to go the other way, and the battery to be charged instead of dischar…

Is that right? I didn't know that. I'd like to see a BOM on a regen braking as compared to a simple disk brake system. One implication to software-only brakes is that it requires that that corner is a drive wheel. If that's the case, I suppose that anti-lock is simply firmware and a sensor. note: I do see that Teslas have master cylinders, so they apparently are hydraulic braking systems.

A bill of materials? As OP said, there is literally nothing required aside from what is required to make the car go forward. An electric motor is a generator.

Teslas have traditional braking systems in addition to the regen braking. The hydraulic brakes have nothing to do with the regen system.

Re: Internal Combustion Engine

#60

Post by pierrec »

Well done. According to the author's Patreon, this is his first article that's "Paid for by patrons" though no details are given. His Patreon is set up so that donations happen whenever he publishes a new article. I guess the advantage over recurring donations is that it doesn't pressure him to crank out content - he can just do it on his own schedule, and donations are always justified.

https://www.patreon.com/ciechanowski

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