The Best way to cut diesel engine operating costs:
Centri ® Air Precleaners

C.F.M. FORMULA

C.F.M.= CUBIC FEET PER MINUTE

For all engines, the C.F.M. can be determined by using the formula below:
2 CYCLE ENGINES 4 CYCLE ENGINES

C.F.M. = C.I.D. x R.P.M. x Vol. Eff.
          1728

C.F.M. = C.I.D. x R.P.M. x Vol. Eff.
          3456
VOLUMETRIC EFFICIENCY: VOLUMETRIC EFFICIENCY:
Diesel Blower-Scavenged = 1.40 Diesel Naturally Aspirated = .85
Turbocharged = 1.90 Turbocharged = 1.60
Turbocharged - Innercooled = 2.10 Turbocharged - Aftercooled = 1.85
Gasoline up to 2500 r.p.m. = .85 Gasoline up to 2500 r.p.m. = .80
2500 to 3000 r.p.m. = .80 2500 to 3000 r.p.m. = .75
3000 to 4000 r.p.m. = .75 3000 to 4000 r.p.m. = .70
C.I.D.-Cubic Inch Displacement   R.P.M.-Revolutions Per Minute   Vol.Eff.-Volume Efficiency

To convert Metric Displacements to C.I.D. for use in the formulas, use the following conversion factors:

Displacement in Cubic Centimeters (cm3) x 0.06102 = C.I.D.
Displacement in Liters x 61.02 = C.I.D.

NOTE: Engines equipped with twin air intake pipes, divide the engine C.F.M. by two and apply the proper CENTRI® Precleaner to each pipe.