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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#81

Post by kingsuper20 »

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…

Very cool. Although I own an LS, I've never touched an LS. The Sloppy Mechanics guy is impressive though.

Since a short block is mostly just a short block, I'll be interested in seeing if LS heads/intake manifold/headers takes off in the SBC community.

Re: Internal Combustion Engine

#82

Post by stjohnswarts »

kingsuper20 wrote: post #58
mfer wrote: post #46

Earlier quoted context omitted.

> 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.

there have been flywheel (only) powered vehicles made. https://en.wikipedia.org/wiki/Gyrobus

Re: Internal Combustion Engine

#83

Post by zeusk »

tmh88j wrote: post #32
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 maint…

Any race or high power engine, especially those that rev quite high will need rebuild - not just in bottom end but often with piston rings and valves as well.

You don't really hear about those other engines much because their buyers understand that a race engine needs more maintenance than any other road car.

Also, not beating on the engine until oil has warmed up to temp will elongate the bearing lifespan quite a bit. I have a friend with E60 6mt S85 that has factory bearings at 110k mi and has perfect oil analysis results.

Re: Internal Combustion Engine

#84

Post by kingsuper20 »

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…

The aero belly of his 1968 Camaro was interesting. The SBC-powered Indy car (probably the last of home-garage built vehicles for that race), the time he drove a NASCAR car back from an impound without the gas tank, etc.

Not to say that cheating didn't happen elsewhere. Check out the front-end sheet metal of the Trans-Am Boss 302s. Use of the headlight holes for brake ducting. The inline Autolite carb. There were some good minds at Holman-Moody, Kar Kraft, Bud Moore, etc.

Re: Internal Combustion Engine

#85

Post by jabl »

legulere wrote: post #35
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

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

Volume matters too, especially for lower stages. There's a reason for the lack of success of hydrolox 1st stages.

Re: Internal Combustion Engine

#86

Post by Robotbeat »

elihu wrote: post #47
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…

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…

Tesla already uses aluminum for power cabling because it’s cheap and lighter weight. Tesla Model S were induction motors (at first at least) with no rare earths, and Tesla is partnering with CATL for lithium iron phosphate batteries in lower cost versions of, if I believe, Model 3 and Y.

Re: Internal Combustion Engine

#87

Post by specialp »

kingsuper20 wrote: post #74
dahfizz wrote: post #59

Earlier quoted context omitted.

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.

I appreciate that now. Thank you to everyone for the education. >The hydraulic brakes have nothing to do with the regen system. I strongly suspect that they interact for antilock. I wonder how Teslas deal with parking brakes, historically kind of an issue with disks. It does seem to me that an entirely regenerative braking system would imply additional expense in terms of the strength of the half shafts, u-joints, tr…

Parking brakes for disc brakes are usually in the center of the disc rotor (like a mini drum) with shoes. Some others like Chryslers have implemented hybrid brake cylinders

Re: Internal Combustion Engine

#88

Post by samstave »

kirse wrote: post #43
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…

Subaru EJ motors munch through rod bearings quite happily.

What are the indicators that replacing them is neigh?

Re: Internal Combustion Engine

#89

Post by mgarfias »

incomplete wrote: post #12

as someone who as a hobby occasionally builds engines (for the 24 hours of lemons), i was really impressed at how incredibly accurate and detailed this whole page is. i'm down w/TDC...

I wasn't. But then I've literally been working on engines since i was a little kid.

Re: Internal Combustion Engine

#90

Post by randlet »

phpdave11 wrote: post #5

This was really educational! I love the design of the webpage, and I especially like how you can rotate the 3d diagrams and see each component from every angle.

If anyone is looking for a hands on educational model, my 6 year old and I put together a model V8 engine [1] (made by Haynes of technical manual fame I think) that does a pretty reasonable job of capturing the essence of the main parts of an internal combustion engine. It kept him (and me) thoroughly engrossed for a few hours.

[1] https://www.themotorbookstore.com/build-your-own-v8-engine-m...

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