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I was explaining the differences between engines to my friend the other day after she heard me say 2.0 liter, 5.7 liter, 6.0 liter......she asked what does the liter mean? What does the liter measure, and how when refering to engine size? All I know is that the bigger the liter the bigger the engine. I may know my cars but the internals of an engine I do not know. Can any of you help me out with this one?
 

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It's the displacement of the engine. A 6.0 liter engine displaces 6 liters of volume. What this means is that if you take the volume difference for each cylinder between fully retracted and at full stroke, you get 6.0 liters. The more volume the engine displaces in a cycle, the more power it produces. This is because more volume of combustion = more gas combusted with more air per revolution = more power generated from each revolution. In theory.

Somebody can feel free to correct me if i'm wrong, but I think that's how it works.
 

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It's the engine displacement. It's basically the bore (diameter of the cylinder) times the stroke (how far the piston travels in the bore) times the number of cylinders. So, the LS2 has a 4.0" bore, a 3.62" stroke and 8 cylinders. So, the formula for displacement is bore * 3.14159 (which is the area of a circle) * 3.62 *8. For those that don't recognize it, the 3.14159 is PI. So, you get 12.56636 *3.62 * 8 = 363.9217 cubic inches. To convert cubic inches into Liters, you multiply 363.9217 by 16.387 (that's the conversion factor for CI to CC) and you get about 5961 CC, and a 1000 CC is a Liter, so it's 5.961 Liter, which I guess is close enough to 6.0 Liter.

Anyhow, that's more math than anyone should have to read about after 3 beers. And I may have rounded a few values, so I'm sorry if I'm off by a few CC's...
 

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catesbros said:
I was explaining the differences between engines to my friend the other day after she heard me say 2.0 liter, 5.7 liter, 6.0 liter......she asked what does the liter mean? What does the liter measure, and how when refering to engine size? All I know is that the bigger the liter the bigger the engine. I may know my cars but the internals of an engine I do not know. Can any of you help me out with this one?
Don't know how to say it breifly so I'll explain it to you:
When the piston moves from top to bottom, it sucks in a certain amount of air, now the amount of air depends on how big around the piston is, and how far it moves from top to bottom. For instance let's just say for sake of argument that the piston in your car is 4in.(10.16 centimeters) in diameter(also known as Bore) and as it moves 4 in from top to bottom(also known as stroke) that means just 1 piston in your engine can suck in: (Get ready for a little math here:D ) Radius ^ pi * height= Volume of a cylinder
5.08cm(Bore/2)^2*3.14*10.16cm(Stroke)=823.3 cubic centimeters now if your car has 8 cylinders, then it's the total displacement of:
8*823.3 cc(cubic centimeters)= 6586.4 cc or 6.586 which the car manufacturer would round up and say your car has a 6.6 liter which means that the displacement of the engine is 6.6 Liters. If you were to turn the crankshaft of the engine 2 complete revolutions, then the 8 pistons would inhale a total of 6.6 Liters of air hope this helps you out in explaining it I know it's long but that's how I learned to do the math.:cheers
 

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vette68 said:
It's the engine displacement. It's basically the bore (diameter of the cylinder) times the stroke (how far the piston travels in the bore) times the number of cylinders. So, the LS2 has a 4.0" bore, a 3.62" stroke and 8 cylinders. So, the formula for displacement is bore * 3.14159 (which is the area of a circle) * 3.62 *8. For those that don't recognize it, the 3.14159 is PI. So, you get 12.56636 *3.62 * 8 = 363.9217 cubic inches. To convert cubic inches into Liters, you multiply 363.9217 by 16.387 (that's the conversion factor for CI to CC) and you get about 5961 CC, and a 1000 CC is a Liter, so it's 5.961 Liter, which I guess is close enough to 6.0 Liter.

Anyhow, that's more math than anyone should have to read about after 3 beers. And I may have rounded a few values, so I'm sorry if I'm off by a few CC's...
OOPs. I screwed up... Smkdu's calculation is right, mine is wrong. The formula for the area of a circle is PI * Radius squared... I used the formula for the circumference, which is PI * Diameter. But the math works out the same in my calculation since the diameter (bore) is 4 and the radius is 2 and 2 squared is 4. So, I happened to luck out with that one and my answers are still mostly correct.

I just had to catch my problem before someone else did.

Man, I need to get a life...:eek:
 

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So when it comes to engines labled as 454s and 402s what's all that about? And how can you calculate an engines initial power band by those listings?
 

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Noraku_6.0L said:
So when it comes to engines labled as 454s and 402s what's all that about? And how can you calculate an engines initial power band by those listings?
Those are the engine's displacements in cubic inches.

302ci and 305ci = 5.0L
327ci = 5.3L
346ci and 350ci = 5.7L
362ci = 6.0L
396ci = 6.5L
402ci = 6.6L
427ci = 7.0L
454ci = 7.4L

Just take the cubic inches and divide by 60.7 or multiply liters by 60.7 to get cubic inches.(Must manufacturers round up). For example, a chevy 350 is 5.7L while a ford 351 is 5.8L

You can't calculate power based on displacement alone. The technology used and the way the engine is tuned matters a lot. Before fuel injection the magic number used to be 1hp per 1 cubic inch but technology has long since made that figure obsolite.
 

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You can't calculate power based on displacement alone. The technology used and the way the engine is tuned matters a lot. Before fuel injection the magic number used to be 1hp per 1 cubic inch but technology has long since made that figure obsolite.
How much horsepower you make per liter of displacement is called the specific output. Cars like Hondas and Ferraris have HUGE specific outputs becuase they build pretty advanced high revving engines. For instance, my old Integra make 170hp from 1.8 liters, thats a specific output of 94hp/L. My 5.7L GTO makes about 61hp/L. If the LS1 made as much specific output as my B18C, it'd make 535hp! Now you want some SERIOUS specific output? Take the new 2.4L F1 V8s, those are making over 700hp from 2.4L, that's OVER 290hp/L!!!!!!!
 

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vette68 said:
It's the engine displacement. It's basically the bore (diameter of the cylinder) times the stroke (how far the piston travels in the bore) times the number of cylinders. So, the LS2 has a 4.0" bore, a 3.62" stroke and 8 cylinders. So, the formula for displacement is bore * 3.14159 (which is the area of a circle) * 3.62 *8. For those that don't recognize it, the 3.14159 is PI. So, you get 12.56636 *3.62 * 8 = 363.9217 cubic inches. To convert cubic inches into Liters, you multiply 363.9217 by 16.387 (that's the conversion factor for CI to CC) and you get about 5961 CC, and a 1000 CC is a Liter, so it's 5.961 Liter, which I guess is close enough to 6.0 Liter.

Anyhow, that's more math than anyone should have to read about after 3 beers. And I may have rounded a few values, so I'm sorry if I'm off by a few CC's...
:eek: holly enstein batman
 

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The stool in the men's room here at work reads,"6 liters/1.6 gallons per flush."

So we have 1.6 gallon engines.

I know, I know--gallons are English units of measure for liquid volume only, whereas liters are metric for both liquid and air volumes. I'm just saying.
 

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GM Kid said:
The stool in the men's room here at work reads,"6 liters/1.6 gallons per flush."

So we have 1.6 gallon engines.

I know, I know--gallons are English units of measure for fluid volume only, whereas liters are metric for both fluid and air volumes. I'm just saying.

UMMMMMMM, air is a fluid.
 

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Actually a gallon is a measure of volume, just like the liter, so your original comaprison to us having 1.6 gallon engines is totally fine. But I doubt anyone is going to go around saying that they have a 1.6 gallon engine, becuase most people associate the gallon with a measurement of how much liquid they have. Damn those milk people.

BTW Sorry to get on you about that, thats just how we engineers are i guess.

Engineers aren't boring people, we just get excited about boring things. :cool
 

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tkd0706 said:
Engineers aren't boring people, we just get excited about boring things. :cool
Ha. Dad was a GM engineer for 30 years, so I know what you mean. I think he hoped I'd follow in his footsteps, but I sucked at math and became a journalism major instead.

I vote we create "1.6 Gallon" hood decals.
 

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EEZ GOAT said:
:eek: holly enstein batman
Thanks... I'll take that as a compliment! :cheers

Although, there was a lot of google searching that went into that post. Had to look up the bore and stroke of the LS2. Now I know it, I didn't before. And I didn't exactly have the CI to CC conversion factor memorized... Had to google that one as well.

Although I really do need to get out more....
 

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The average ten-gallon hat only holds about 3 quarts (2.84 L).

So we could really call our engines "20 gallon" engines, especially if you wanted to tick off the tree-huggin' crowd.

(In the metric world, fuel economy is measured in liters per 100 km driven, so a lower number means higher economy).

1 Gallon is about 3.787 liters.
100 KM is about 62.5 miles.

If our goats take 3 gallons of fuel to go 62.5 miles (20.83 mpg), this would be 11.36 liters per 100 km.
If a Honda Insight can go 62.5 miles on 0.9 gallons of gas (69.44 mpg), this would be 3.41 liters per 100 km.

But it's still more fun to drive the goat for 62.5 miles. :D
 
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