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Internal Combustion Engine

ciechanow.ski

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Re: Internal Combustion Engine

#201

Post by mulmen »

mrfusion wrote: post #189

Isn’t it risky for the timing to rely on a rubber belt? Does it never slip? Even a mm of slippage seems like it would make the valve timing stop matching the pistons?

My first car would diesel after turning it off. Basically the engine would keep running on fuel in the carburetor and residual heat in the engine. Sometimes it would do this backwards. This was very problematic because the timing belt tensioner only worked in one direction. When it ran backwards the timing belt would jump a tooth then the car would not start. I got in the habit of just killing the motor with my foot on the brake and the car in gear then letting the clutch out.

I also had the machine shop at my high school weld up a custom tool to help me reset the timing belt in a parking lot with a couple of hand tools. It could be done in a few minutes.

This is a long way of saying yes, if they slip it is bad.

Re: Internal Combustion Engine

#202

Post by 49yearsold »

This is unbelievably awesome! I wish I had such material and teacher like Bartosz Ciechanowski when I was learning IC engine during my undergrad for mechanical engineering. Thanks a million to Bartosz wherever you are and whoever you are! Simply wonderful! Thank you, thank you, and thank you!

Re: Internal Combustion Engine

#203

Post by bluedino »

pjc50 wrote: post #195
mrfusion wrote: post #189

Isn’t it risky for the timing to rely on a rubber belt? Does it never slip? Even a mm of slippage seems like it would make the valve timing stop matching the pistons?

Timing belts have teeth. Occasionally chains are used instead; more expensive and heavier, but more durable. You do need to maintain the timing either way it it will destroy the valves.

If the engine is a non-interference design, losing the belt won’t be catastrophic for the valves

Re: Internal Combustion Engine

#204

Post by TheSpiceIsLife »

blamazon wrote: post #196
mrfusion wrote: post #189

Isn’t it risky for the timing to rely on a rubber belt? Does it never slip? Even a mm of slippage seems like it would make the valve timing stop matching the pistons?

In addition to what frosted-flakes said, many engines are “non interference” design so that if the belt snaps or jumps a tooth the engine won’t be destroyed, and the belt will just need to be replaced. However, non interference engines are not as compact as interference engines. Many engines also use a timing chain instead of a timing belt, but this carries extra weight and requires lubrication. It’s all about tradeo…

The engine in one of the vehicles I own has timing gears rather than a chain or belt. Another option, different trade-offs.

Re: Internal Combustion Engine

#205

Post by specialp »

Grazester wrote: post #113
specialp wrote: post #67

Earlier quoted context omitted.

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 s…

I have a buddy that is adamant about not flushing transmissions if you dont have a issue because he think its guaranteed to have an issue after, from his experience. lol

I'd concur with that. Note this was one of the notorious to fail JATCO nissan/mitsubishi transmissions. Blowing fluid through with pressure makes no sense. Sediment sitting in pans does not affect operation until it is agitated into suspension

Re: Internal Combustion Engine

#206

Post by [deleted] »

blamazon wrote: post #196
mrfusion wrote: post #189

Isn’t it risky for the timing to rely on a rubber belt? Does it never slip? Even a mm of slippage seems like it would make the valve timing stop matching the pistons?

In addition to what frosted-flakes said, many engines are “non interference” design so that if the belt snaps or jumps a tooth the engine won’t be destroyed, and the belt will just need to be replaced. However, non interference engines are not as compact as interference engines. Many engines also use a timing chain instead of a timing belt, but this carries extra weight and requires lubrication. It’s all about tradeo…

[deleted]

Re: Internal Combustion Engine

#207

Post by philg_jr »

specialp wrote: post #174
philg_jr wrote: post #168

Earlier quoted context omitted.

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 :)

It was and still will be supercharged. It was 650 crank Hp, and will be over 800 conservatively . and its manual ;)

Yep. Jealous. Best of luck on the build!

Re: Internal Combustion Engine

#208

Post by therein »

I have always wondered, if it would be possible to make a small enough internal combustion engine so that you could just have it laying around in an apartment, sitting a few feet away from you, powering your appliances or charging a 12V or 24V battery. Dispensing the exhaust through a long tube. If all goes well, complete combustion of propane should yield CO2 instead of CO anyway. An additional enclosure shouldn't be an issue given the generator is small enough anyway.

The smallest propane powered generator I can find is basically still not much more silent or smaller than Honda EB2200.

Imagine a 350W generator that you can connect to a camping style propane tank that you use to charge some batteries.

I played around with setting up such a system with a Sterling engine but couldn't achieve high efficiency.

Surprised to see no YouTuber with the necessary machining skills and CNC equipment attempted to build a mini internal combustion engine / inverter generator.

Re: Internal Combustion Engine

#209

Post by alanbernstein »

A few thoughts while reading this:

In addition to a deeper understanding of engine manufacturing considerations than I even knew I cared to learn, this article helps me appreciate why people are into engine work.

The perfect tolerances and synchronization of these machines makes me a little ashamed to use the word "engineer" in my title of "software engineer". There is no real comparison of the quality of the result.

And then I skimmed the source, and it makes me think the author deserves that title. It also validates my belief in vanilla javascript.

edit: And later it occurs to me that Mr. Ciechanowski is a true craftsman of software; handmade and built to 1) Be beautiful (and informative), 2) last for years. (The open web standards are the ones that seem to stick around the longest, for better or for worse. (I'm ignorant of the shader world though))

Re: Internal Combustion Engine

#210

Post by CRConrad »

TheSpiceIsLife wrote: post #204
blamazon wrote: post #196

Earlier quoted context omitted.

In addition to what frosted-flakes said, many engines are “non interference” design so that if the belt snaps or jumps a tooth the engine won’t be destroyed, and the belt will just need to be replaced. However, non interference engines are not as compact as interference engines. Many engines also use a timing chain instead of a timing belt, but this carries extra weight and requires lubrication. It’s all about tradeo…

The engine in one of the vehicles I own has timing gears rather than a chain or belt. Another option, different trade-offs.

Much more common with pushrod engines, where the camshaft is situated close to the crankshaft; less so with overhead camshafts. Though I think some very high-revving sports and competition engines have gears driving overhead cams; IIRC the McLaren TAG F1 turbo V6 (by Porsche) back in the 1980s was one example.
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