Compression?

[alacuesta]

When I watch this video, I don't understand where the compression is coming from? How is it happening?????

On a side note, please tell me because it's driving me flippin' crazy.

http://www.youtube.com/watch?v=o_QyUD6V5_I

On a side note - the way I understand compression is there has to be a top of the cylinder but there doesn't appear to me that there is one. Hope that makes sense.

Thanks!

[PhillipM]

I don't get what you mean? Of course the top end is on the engine, you can see the cylinder heads bolted down!?

[l4mbch0ps]

I think perhaps your are confusing what you are looking at...

We are seeing the tops of the intake trumpets, with the injectors spraying fuel downwards towards the intake valves.
I think perhaps you have confused this with the combustion chambers. Remember, because this is an older engine, the fuel is not injected directly into the cylinder, but rather into the intake tract before the valves.

[alacuesta]

Thanks for the reply, guys. You are definitely talking above my head because I simply don't get it.

I have a lot of learning to do. With that said, and from what I can see, when I work on my own car and change the spark plugs out, there are plugs on top, which from what I've learned, are a part of the top of the cylinder head.

When I watch this video, I see injectors spraying fuel into 'something', which does not involve a spark plug nor a cylinder head. That goes back to myself asking the question where does the compression come from? Are F1 engine combustion chambers inverted? If so, how are they different than my car? I'm confused. Argh!!!

Just an fyi - I'm a very visual learning kind of person. If anyone has a video that can show me, rather than explain it verbally, I would really appreciate it. This is driving me nuts and I am frustrated because I can't figure it out!

Thanks again.

[Moxie]

Sometimes people have a hard time relating the pictures in diagrams to real life. I'll try to help, but I don't know how to post pictures here, so please follow my directions.

Google internal combustion engine and download an image of a four stroke cylinder, and print it to paper.

That picture is most likely oriented so that the piston travels vertically. The picture will show the valves at the top of the cylinder, and tubes leading to the valves. One of the tubes will be labeled "intake", and the other will be labelled "exhaust."

Now take that picture and rotate it 60 degrees so that the intake tube enters the cylinder from the top, and the exhaust tube exits from the bottom. Those holes you see in the video are the tops of those intake tubes (trumpets). The fuel injectors shoot fuel into these trumpets, and you can see this in the video. You cannot see the valves which keep the cylinder sealed during compression, and you cannot see the spark plug, because those items are buried under the rest of the machinery that makes it all work.

[tim|away]

here's a basic video on how a combustion engine works.

[youtube]http://www.youtube.com/watch?v=zA_19bHxEYg[/youtube]

[Dangpr]

That engine is different from the one you find in your road car.

Those are stand off injectors, what they are spraying into is not the combustion chamber, but individual trumpets (before the intake valves)