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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#161

Post by scythe »

esaym wrote: post #93
elihu wrote: post #47

Earlier quoted context omitted.

The raw materials may continue to cost more for EVs. Motor windings are generally copper, and batteries contain lithium and (usually) cobalt and nickel. Permanent magnet motors sometimes contain rare earths. One could make an EV with aluminum motor windings and electrical cabling, no rare earth magnets, and lithium iron phosphate batteries. That would keep expensive materials to a minimum. EVs don't need a catalytic…

> EVs don't need a catalytic converter, so that's a big thing in their favor. I feel there is some sort of scam going on with catalytic converters for the last few years. I actually worked in a small family owned auto shop in the early 2000's. If a car came in with a clogged cat, we'd first fix the source of the issue (usually a mis-firing cylinder allowing raw fuel into the exhaust) and then we'd cut out the cat, an…

Catalytic converters don't reduce greenhouse gases. Their function is to reduce poisonous gases: NO, NO2, O3, CO, HO2, and sometimes HCN and H2CO. The good news is that all of these compounds are thermodynamically unstable so a catalyst can destroy them.

I don't know where you got the 14.7:1 number but I am certain that NOx are unstable at any concentration (at or near STP) and will always be depleted by a catalyst.

Another commenter is unsure whether the NOx or some GHGs should be reduced preferentially. To clarify: CO2 can't be removed, it is stable; only CH4, N2O and O3 can be removed, and they are not present at relevant levels (except ozone which is poisonous) anyway. The poisonous gases are far more important — NOx pollution alone kills thousands of people every year (statistically, considering excess deaths as correlated to air pollution).

The increased price of catalytic converters is partially related to the supply of palladium, which experienced a glut following the collapse of the USSR. The Soviet palladium ran out in 2012:

https://www.mining.com/russias-stockpiles-said-to-be-deplete...

Re: Internal Combustion Engine

#162

Post by specialp »

tmh88j wrote: post #123
esaym wrote: post #106

Earlier quoted context omitted.

It sounds like he wanted some very precise work done. Quality in the blue collar trades has gone to nil in the last decade. And if you do find someone that is very detailed and "by the book" level of quality, you are going to pay 3X the normal labor rate. For instance, this is a performance transmission shop [0] that regularly takes apart "precision" rebuilt transmissions only to find they were not done right at all.…

LS engines are among the most common engines in custom built cars, and there are countless shops out there who specialize in them. No offense to him or you, but it's quite ridiculous to believe you can do a better job building an engine on your first try than shops like Texas Speed who have been doing it for decades with full blown R&D labs and regularly build 2000+ horsepower motors, all with highly skilled machinis…

I could do a better job than them in all due respect. I care about my job more than anyone on earth. I know they do good work but if we could both measure to the same specs and know we did it right, how could I do it worse than them. we have the same measuring tools. Not that I think they do bad work. But if you ever built an engine you know its all about attention to detail. there is nothing they have to verify the integrity of the build that I don't to a similar level of precision.

Edit: I dont have the machines they do, but when my bare block comes back from the machine shop, my tools are just as good as theirs to verify the dimensions are correct. That isn't possible to verify with a built short or long block. They could possibly have 100 employees that care as much about my job as me who knows. This is a job about verification of specs and assembling correctly not of insane tech. They don't have anything I dont when assembling an engine. Machine work yes

Re: Internal Combustion Engine

#164

Post by qwertox »

One of those web pages which deserves an award. Some place in some kind of Internet Hall of Fame, an historical archive which shows the only best highlights of what websites were actually capable of presenting. Milestones of web development.

This page summarizes pretty good what web technology is capable of, when in the hands of a real professional.

---

Ok, I just realized this is from Bartosz Ciechanowski, and this reminded me of the Cameras and Lenses [1] article which I've seen recently. It was the same kind of quality.

This man is a real genius.

[1] https://ciechanow.ski/cameras-and-lenses/

Re: Internal Combustion Engine

#165

Post by Severian »

toxik wrote: post #79

This was excellent, but should perhaps be clarified that this is a gasoline engine - diesels don’t ignite by spark, but by immense pressure in the chamber. This also invalidates the “you cannot add fuel to increase power” of gasoline engines. Diesels can (and should!) run at lower rpm; they don’t stall because the ECU can add fuel to increase power output.

And thus the reason why there's such as thing as a runaway diesel engine.

Re: Internal Combustion Engine

#166

Post by gtvwill »

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 use inches here because in machine work thousandths of inches is the language du jour."

Yeah not in Australia unless your machinist is >50 years old. Metric is more accurate/easier/less prone to mistakes. Metric is what we use.

Re: Internal Combustion Engine

#167

Post by jbay808 »

the_cat_kittles wrote: post #77
elihu wrote: post #47

Earlier quoted context omitted.

The raw materials may continue to cost more for EVs. Motor windings are generally copper, and batteries contain lithium and (usually) cobalt and nickel. Permanent magnet motors sometimes contain rare earths. One could make an EV with aluminum motor windings and electrical cabling, no rare earth magnets, and lithium iron phosphate batteries. That would keep expensive materials to a minimum. EVs don't need a catalytic…

cmon man. the total weight of pricey metals in a car is so low, there is no way its going to offset the cost of precision machining. tolerances < 1 thou and callouts for surface finish and perpendicularity are expensive!

Hard to say. Those tolerances would be expensive in general purpose machine work, but in engines those tolerances have been in place since at least the 1930s, and so economies of scale bring those costs down (ie, using specialized machines that are really good at boring precision holes and measuring them. The costs of those machines get amortized over every engine).

Re: Internal Combustion Engine

#168

Post by philg_jr »

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…

Damn, dropping a new engine in a CTS V? What year? NA? How much power are you shooting for? The CTS V is definitely one of my favorite cars, I'd love to own one one day, but the ones with the manual trans hold their value pretty well :)

Re: Internal Combustion Engine

#169

Post by TwoBit »

Syonyk wrote: post #140
samstave wrote: post #94

Earlier quoted context omitted.

How was he "caught" if thats the term?

I would assume that by some point, if one of his cars won, the officials just took the whole thing apart to find out what sort of bizarre loophole he'd found that met the letter of the requirements while totally violating the spirit. His antics weren't secret, even at the time he was working. He was just really good at it.

And nobody considers that dishonest? It's cheating in the spirit of the rules if not the letter of the rules.

Re: Internal Combustion Engine

#170

Post by globular-toast »

ryandrake wrote: post #135
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…

Not only the tight measurements, but I've always been amazed at the precise timing of all the little moving parts, the valves all opening and closing at precise to-the-millisecond times so that each stroke happens, at 6000 RPM! So impressive. Especially with an interference engine, where getting that timing wrong means bent valves.

Mmm.. not really. It's just a cam and a spring. Pretty easy to get that bit working by yourself. Variable valve timing and lift is much more impressive.
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