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POPULAR RACING FORMULAS

Engine Cubic Inches = Bore (in.) X Bore (in.) X Stroke (in.) X number of Cylinders X .7854

Engine Cubic Liters = Bore (mm) X Bore (mm) X Stroke (mm) X Number of Cylinders X .7854

Find the Stroke When The Bore And Cubic Inches Is Known:
Cubic Inches or Liters ÷ Bore ÷ Bore ÷ .7854 ÷ # of Cylinders
Example: Chevy 350
350 ÷ 4.000 = 87.5 ÷ 4.000 = 21.875 ÷ .7854 = 27.852 ÷ 8 = 3.482

Find the Bore When The Stroke And Cubic Inches is Known:
Cubic Inches or Liters ÷ Stroke ÷ .7854 ÷ # of Cylinders then find Square Root of This Answer
Example: Chevy 350
350 ÷ 3.480 = 100.575 ÷ .7854 = 128.056 ÷ 8 = 16.007
Look up 16 on the Square Root Table below and the Square Root is 4.000

 

SQUARE ROOT TABLE:

No. Sq. Root No. Sq. Root No. Sq. Root No. Sq. Root
1 1.000 10 3.162 19 4.359 28 5.292
2 1.414 11 3.317 20 4.472 29 5.385
3 1.732 12 3.464 21 4.583 30 5.477
4 2.000 13 3.606 22 4.690 31 5.568
5 2.236 14 3.742 23 4.796 32 5.657
6 2.449 15 3.873 24 4.899 33 5.745
7 2.646 16 4.000 25 5.000 34 5.831
8 2.828 17 4.123 26 5.099 35 5.916
9 3.000 18 4.243 27 5.196 36 6.000
 

Head Gasket Volume = Gasket Bore (in.) X Gasket Bore (in.) X 12.87 X Compressed Gasket Thickness = gasket volume in CCs. Note : gasket bore diameters are usually about .060 larger than the cylinder bore diameter.

Deck Volume = Bore Diameter X Bore Diameter X Deck Height X 12.87 = Deck Volume in CCs.

CONVERSIONS:
1 Cubic Inch = 16.38 CCs
Cubic Inches to CCs = Cubic Inches X 16.38
Cubic Inches to Liters = Cubic Inches X .01638
CCs to Cubic Inches = CCs divided by 16.38
Liters to Cubic Inches = Liters divided by .01638