Computech Systems RaceAir Pro - Page 39

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39
Compression Ratio, Find Combustion Chamber Volume.
This program computes the combustion chamber volume in cubic centimeters (CC) required to
achieve a desired compression ratio.
Press ALT, ENGINE FORMULAS, then C/R Menu, then select Calc Chamber to start this
program.
Display Example:
==Calc Chamber==
Bore? 4.250 (Enter cylinder bore diameter inches)
Stroke? 3.750 (Enter crankshaft stroke inches)
Boost? 0.000 (Enter max manifold pressure PSI gage)
Deck Hgt? 0.020 (Enter TDC piston to block deck clearance inches -
use negative number for piston above deck -0.020)
Gskt Vol? 12.600 (Enter head gasket volume CC, enter 0 if not known)
New C/R? 11.00 (Enter desired engine compression ratio)
Dome Vol? 8.30 (Enter piston dome popup volume CC)
Chamber= 78.20 (Calculated head combustion chamber volume CC
to achieve desired compression ratio)
Compression Ratio, Find Piston Dome Volume.
This program computes the effective piston dome volume in cubic centimeters (CC) required to
achieve a desired compression ratio.
Press ALT, ENGINE FORMULAS, then C/R Menu, then select Calc Dome to start this program.
Display Example:
=== Calc Dome===
Bore? 4.250 (Enter cylinder bore diameter inches)
Stroke? 3.750 (Enter crankshaft stroke inches)
Boost? 7.500 (Enter max manifold pressure PSI gage)
Deck Hgt? 0.020 (Enter TDC piston to block deck clearance inches -
use negative number for piston above deck -0.020)
Gskt Vol? 12.600 (Enter head gasket volume CC, enter 0 if not known)
New C/R? 11.00 (Enter desired engine compression ratio)
Chamber? 78.200 (Enter head combustion chamber volume CC
Use FLAT TOP (Use flat top piston and
with 0.131 deck piston down in bore dimension inches)
or dome= -25.70 (Press ENTER to continue)