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MACHINING CYLINDER HEADS FOR PROPER INTAKE MANIFOLD ALIGNMENT:

After machining the head at surface A, material should be machined from surface B for proper intake manifold alignment.  Note how the bolt holes in the intake manifold do not line up after machining the head gasket surface A. 

The amount of corrective machining required varies with the angle at which the head is made.  Head angle is the variance from 90 degrees.  For instance, a head that has the head gasket and the intake manifold surface made at a right angle (90 degrees) to each other would be classified as a 0 degree head.

0 Degree Head Angle (Big Block Ford & Oldsmobile)
Amount Removed at "A" x 1.0 = Amount to be removed at "B"

5 Degree Head Angle
Amount Removed at "A" x 1.1 = Amount to be removed at "B"

10 Degree Head Angle (Small Block Chevy)
Amount Removed at "A" x 1.2 = Amount to be removed at "B"

15 Degree Head Angle (Chrysler, Y Block Ford)
Amount Removed at "A" x 1.4 = Amount to be removed at "B"

20 Degree Head Angle (Oldsmobile 303, 324, 371 and 394)
Amount Removed at "A" x 1.7 = Amount to be removed at "B"

25 Degree Head Angle (Cadillac, Dodge, Plymouth)
Amount Removed at "A" x 2.0 = Amount to be removed at "B"

30 Degree Head Angle
Amount Removed at "A" x 3.0 = Amount to be removed at "B"

On some engines, it is necessary to remove stock from the intake manifold bottom if the heads have been surfaced.  The amount required varies with the head angle.

0 Degree Head Angle (Big Block Ford)
Amount Removed at "A" x 1.4 = Amount to be removed at "C"

10 Degree Head Angle (Small Block Chevy and Ford)
Amount Removed at "A" x 1.7 = Amount to be removed at "C"

CONVERSION FORMULAS:

Inches x 25.4 = mm

mm x .03937 = inches

cubic inches x 16.387 = cubic centimeters

liters x 61.025 = cubic inches

1 da (N*m) = 7.373 foot pounds

foot pounds x 12 = inch pounds

foot pounds x 1.355 = newton meters (N*m)

foot pounds x 1.383 = kilograms/meter (Kg/m)

cubic fee x 7.481 = gallons

liter x .2642 = gallons

gallon x 3.785 = liters

gram x 0.3527 = ounces

gram x .0022 = pounds

Kg x 2.1 = pounds

psi x 6.895 = kilopascals (kPa)

kilopascals (kPa) x .145 = psi

psi x .069 = bars

bars x 14.5 = psi

mph x 1.609 = kilometers/hour (km/h)

horsepower (hp) x .746 = kilowatts (kw)

kilowatts (kw) x 1.3405 = hp)

(degrees Fahrenheit) -32 Degrees) x .555 = degrees Celsius

(degrees Celsius x 1.8) + 32 Degrees = degrees Fahrenheit

Surface feet/minute = 3.1416 x diameter x rpm

Displacement:

stroke x (1/2 bore)2 x 3.1416 x (# of cylinders) = displacement or:

8 cylinder: 6.283 x stroke x bore x bore = displacement

6 cylinder: 4.712 x stroke x bore x bore = displacement

4 cylinder: 3.1416 x stroke x bore x bore = displacement

QUICK CHECK ENGINE COMPRESSION RATIOS:

All volume measurements in CC's. The calculation of an engine's compression ratio (C.R.) is based on the formula:

C.R. = S.V. + C.V.
                 C.V.

where S.V. = swept volume for one cylinder (volume in CC's)

                    = bore x bore x stroke x 12.9

C.V. = clearance volume for one cylinder (volume in CC's)

         = H.V. minus E.D.V. plus D.V. plus G.V.

H.V. = head volume (published or measured in CC's)

E.D.V. = effective dome volume (published or measure in CC's)

             = dome volume minus valve relief and/or dish volume

D.V. = deck clearance (between piston and deck surface) volume in CC's

         = bore x bore x deck height x 12.9

G.V. = gasket volume in CC's

         = gasket bore x gasket bore x compressed thickness x 12.9
            or enter known gasket volume