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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#61

Post by BrentOzar »

jborichevskiy wrote: post #57
Syonyk wrote: post #36

Earlier quoted context omitted.

> 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?

Your fuel tank was only allowed to hold a certain amount of fuel because if you had more, you could go farther between pit stops, thereby covering more laps while the other drivers were stopped for gas.

He would temporarily meet the small tank regulations during inspection, but under race conditions, the ball would burst, allowing for more space in the tank, which would get filled up with more fuel than his competitors at the first pit stop.

Re: Internal Combustion Engine

#62

Post by londons_explore »

kirse wrote: post #37
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.

As soon as governments get serious about CO2 emissions, Hybrid powertrains will end up as a "worst of both worlds" position.

Already across most of Europe all subsidies and discounts that applied for "eco friendly cars" no longer apply to Hybrids.

That leaves few people wanting to buy a hybrid - it won't be cheapest or most eco friendly.

Re: Internal Combustion Engine

#63

Post by ska »

jborichevskiy wrote: post #57
Syonyk wrote: post #36

Earlier quoted context omitted.

> 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?

I suspect that it increased the fuel capacity from the nominal "max" at race start, so when you hit a pit stop you can put more in.

Re: Internal Combustion Engine

#64

Post by elihu »

kingsuper20 wrote: post #26
bob1029 wrote: post #11

Earlier quoted context omitted.

Reciprocating machines are fairly remarkable when you consider all of the components involved, forces, etc. Even more so when you think about how long a typical car engine lasts. These incredible forces are why rotary and turbine engines are substantially more reliable. Some gas turbines have only 1 moving part, and in some applications this moving part experiences zero wear due to magnetic/aerodynamic/active bearing…

Rotaries are a funny case. Look good on paper. Thermal efficiency issues. Smog. Seals. Noise control difficulties. Weird patches like bridge ports. For modern passenger cars, it's kind of like overcoming the difficulties of two-stroke. In anti-defense of 4-stroke ICE, it seems to me like we are hitting peak wacky complexity of those. Variable timing cams, turn off the cylinders, direct port injection, turbos, variabl…

> Thank God electric cars are becoming more available, although I fear increasingly complex cooling and battery management and the 1000 things a software guy is going to add to them.

I'm hoping lithium iron phosphate starts to be used more in midrange vehicles; partly because they can be scaled up while sidestepping the potential resource bottlenecks around cobalt and nickel, and partly because they're very durable and cooling isn't usually much of an issue. Though heating might be an issue in the winter time (most LFP cells don't like being charged when temperatures are below freezing; heating might be necessary in winter).

Re: Internal Combustion Engine

#65

Post by [deleted] »

jborichevskiy wrote: post #57
Syonyk wrote: post #36

Earlier quoted context omitted.

> 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?

[deleted]

Re: Internal Combustion Engine

#66

Post by WalterBright »

jborichevskiy wrote: post #57
Syonyk wrote: post #36

Earlier quoted context omitted.

> 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?

Fuel capacities are reduced to minimize the fire in fiery crashes. But lower fuel capacity means more pit stops, which the racer wants to minimize.

Temporarily reducing fuel capacity means the car passes tech inspection, but really has more capacity.

Re: Internal Combustion Engine

#67

Post by specialp »

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…

Yes you are right as far as LS engine builders there's loads. I could have ordered a crate engine from Texas Speed and been done with it. And yes for hours of my time spent vs hours of money saved I lost a ton of money. But all it takes is one very small mistake to make an engine short lived with these exacting tolerances. I'd rather blame myself than deal with someone kicking the blame back. It was also a personal satisfaction thing.

My wife's engine had an issue and it was the middle of winter so I said whatever let's just have a shop fix it. In the process they "flushed the transmission" and it failed 4 days after we got the car back. Of course they stonewalled us and I can't prove they broke it. So I ordered a late model wreck transmission and replaced it and 3 years later still running strong.

But I then decided that I would never be in that position again where someone could tell me it wasn't their problem and get me aggravated. With this engine I built it from raw parts. I had the block machined, and I had the tools to verify.

It was certainly not worth my time, but as you said I love working on cars too.

Re: Internal Combustion Engine

#68

Post by rsj_hn »

dahfizz wrote: post #42
Viker wrote: post #25

Earlier quoted context omitted.

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

This sparked my curiosity... Currently gasoline has about 50x more energy per unit weight than a tesla battery pack. Battery energy densities have tripled in the past 10 years. Keeping on that pace, it would take over 30 years for batteries to be competitive with gas. When you account for the astoundingly bad efficiency of ICE, though, the gap in usable energy decreases. This is why a tesla can go 300+ miles with a b…

The Tesla can go 300 miles by making it light, aerodynamic, brakes that recharge the battery, not turning on the heater, etc. Yes, it's a significant engineering accomplishment, but in the heavy long haul world when analyzing break-even points what matters is range improvements due to an increasing energy/weight ratio, not range improvements due to reducing air resistance and inertia. This is because the form factors of the boxcar are basically set by shipping container needs and the weight is going to be determined by the load you are carrying. Munro is advocating for hydrogen powered trucks and planes as hydrogen has similar power/weight characteristics to gas -- electrification of these is going to be a challenge.

Re: Internal Combustion Engine

#69

Post by [deleted] »

jborichevskiy wrote: post #57
Syonyk wrote: post #36

Earlier quoted context omitted.

> 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?

[deleted]

Re: Internal Combustion Engine

#70

Post by Syonyk »

jborichevskiy wrote: post #57
Syonyk wrote: post #36

Earlier quoted context omitted.

> 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?

Fuel tank capacity is required to be 10 gallons. Say, 20 laps or so.

They check, at the tech inspection, that your tank doesn't hold more than 10 gallons. Great.

Except, once you deflate the basketball (or get creative with routing fuel lines all over the car), you actually have 11-12 gallons onboard.

Which means, at the end of the race, when everyone else has to pit, you can make the "risky option" to skip the final pit stop, keep rolling, and, well, surprise of surprise, make it over the line (in first place) before you flame out.

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