Calculated Industries 8703 - Manual (Page 50)

compression ratio, whereas raising the overall chamber volume
will decrease the compression ratio. Piston Dome, Deck Height,
and Head Gasket Thickness are several ways to effect your
compression ratio. In the next section, you can read about one of
the more popular ways to increase compression ratio, which is a
process known as milling.
Calculating Mill Amount
Another method of increasing the compression ratio on your
engine is to mill, or remove material from, the heads. Generally,
you will have a target compression ratio you want to achieve and
you want to determine how much material to remove from your
engine’s heads.
Note: Your Hot Rod Calc user’s guide does not go into details on
the milling process. Your local engine building shop will likely have
the necessary knowledge and tools for milling your heads to your
specs.
For this example, you want to increase your compression ratio from
8.5:1 (current Compression Ratio) to 10.5:1. Your Stroke is 3.84
inches. The following keystrokes will show you how to calculate the
amount to mill:
KEYSTROKES DISPLAY
 0.
1. Enter your Stroke and current Compression Ratio:
 STROK S 3.48 IN
 COMP S 8.5 RATIO
2. Enter your target Compression Ratio, and calculate the Mill
Amount:
 MILL 0.098 IN
Repeated presses of  will toggle through the inputs and outputs,
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