Engine Displacement Calculator

Can someone explain why a cubic centimetre is not the same value a millilitre (and yes, we do spell them that way over here). My chemistry teacher a school several decades ago just mumbled.
 
I came up with 199 cu.in for an engine of 4.125 x 3.875 with a .040 oversize piston, The figure given in " The Ford Model A, As Henry Built It" is 200.5 cu.in. without the overbore. Something isn't right.
Terry
 
Here is the information as I know it for a Model A engine

Mac's for example has a cheat sheet to use

http://macsautoparts.com/ford-model-a-specifications-page/camid/MDA/ca/215/#engine



Bore 3.875
Stroke 4.250

Giving this
http://www.bgsoflex.com/cgi-bin/displacement.cgi?ncyl=4&diam=3.875&osize=0&stroke=4.250&mode=Inches

So 40 oversize gives a whopping 5 CU more - no wonder I was able to pass that farm tractor yesterday

http://www.bgsoflex.com/cgi-bin/dis...iam=3.875&osize=.040&stroke=4.250&mode=Inches
 
johnbuckley said:
Can someone explain why a cubic centimetre is not the same value a millilitre (and yes, we do spell them that way over here). My chemistry teacher a school several decades ago just mumbled.
Click to expand...
The metric system started in Paris in 1793. The LITRE (your spelling) was first defined as a measure for liquids, then as a 10cm cube.

More precision was needed for science and engineering during the industrial revolution. In 1889 the "Standard Kilogram" was created. This was supposed to be the same mass as 1 liter of water at 4 degrees celsius. (4°C is water's max density point, that is why the water at the bottom of a half-frozen lake is at 4°C, not 0°C.) The LITER then became officially defined as 1 kilogram of pure water at 4°C.

There was a very small error detected in 1907. The "1889 Standard kilogram" was discovered to have a mass equal to 1000.028 cc of pure water at 4°C, not 1000 cc as originally intended. Using the "1889 Standard kilogram" water at 4°C equal to that mass occupied exactly 1000.028 cc., not 1000.000 cc Quite a screw up.

It was decided in 1907 to leave the kilogram (mass) as the "Standard" and change the liter (volume standard) from it's original definition of a 10cm cube. Alternatives would have been to change the standard meter (length) or change the mass standard.
So now 1 milliliter = 1.000028 cc and 1 cc = 0.999972 ml.

There is also a story about whether the foot should be measured before or after the king trims his toenails, but that story stinks, so don't ask.
 
Ok Mark, Not being satisfied, I went out to an engine I'm rebuilding and measured the stroke, As you said, it's 4.250". Still not content, I went back to "As Henry Built It" and re read page17, eng. Specs., Bore and stroke, 3.875 X 4.125! Hmmmmm Not My error this time. Ok I'll recalculate.
Terry
 
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