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

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...

Don't know how to say it breifly so I'll explain it to you:catesbros said:

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 ) 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

I know the horsepower rating system too:cool

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smkdu said:I know the horsepower rating system too:cool

All very informative. So what is the HP calculations?

Torque * RPM * conversion constant (forgot the exact number)smkdu said:I know the horsepower rating system too:cool

Pretty simple.

*edit* HP = TQ * RPM / 5252

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.vette68 said:

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...

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

Man, I need to get a life...

Y'all still blew my mind but very good info. Learn something new everyday.

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Those are the engine's displacements in cubic inches.Noraku_6.0L said:

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.

How much horsepower you make per liter of displacement is called theYou 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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holly enstein batmanvette68 said:

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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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.

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

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See edits. Better?tkd0706 said:UMMMMMMM, airisa fluid.

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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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.tkd0706 said:Engineers aren't boring people, we just get excited about boring things. :cool

I vote we create "1.6 Gallon" hood decals.

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

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....

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.

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