This form is a basic engine calculator to help you determine engine capacity from the bore and stroke along with the static dynamic and effective compression ratio's.

Most Aircooled engines do not use 'sealing rings' so you can safely leave those values set to zero, however some performance forced induction and Type 4 engines use copper sealing rings at the cylinder to head mating interface. 

The form is pre-loaded with the values for a stock 1600cc engine running 5psi of boost

Using deck height to control, set or adjust CR is far from optimal. The deck height value is also responsible for setting the quench height - this is the distance between the piston and flat area of the head at TDC, also known as the quench or squish pad.

The action of the cylinder at TCD meeting the quench pad forces the charge out from this area and causes it to move into the open part of the chamber, this action helps to both mix and 'squish' the charge within a smaller confined area nearer to the spark plug. This promotes flame propagation and minimises the effects of detonation.

Increasing deck height too much minimises this 'squish' and also allows the charge to spread out across the chamber, prolonging flame propagation and increasing the risk of detonation (areas of uncontrolled ignition ahead of the flame front).

Ideally deck height needs to be kept around 1mm or less and any changes required to adjust the static CR should be done by altering the shape and size of the combustion chamber or piston crown.

It should be noted that reducing deck height too much increases the risk of piston to head contact.

Static compression ratio is the ratio of swept volume to static volume of combustion area with piston at TDC under atmospheric conditions. It is a fixed ratio and a basic representation of the compression ratio whic is an indication of the amount that the intake charge is compressed during the compresson cycle.  Unfortunately it is only indicative of the pressure that your engine actually see's in use as it does not take into account valve opening times or boost.

The dynamic compression ratio, is the same ratio but takes into account the opening and closing of the valves along with the rod geometry. 

The Effective CR is the dynamic CR with the addition of any boost introduced into the system. This is indicative of the actual pressures that your engine will see in operation.

It should be noted that in all cases, additional cylinder stuffing as a result of cylinder scavenging is not accounted for.

A low CR + high boost engine is much more detonation resistant. But why?

• Reduced Initial Thermal Load: Low static compression keeps the combustion chamber cooler before ignition.
• "Room" for Airflow: Lowering the compression ratio lowers peak cylinder pressure, allowing for higher mass airflow (more boost) before reaching the threshold where fuel auto-ignites (detonation).
• Timing Flexibility: Because the mixture is less prone to spontaneous combustion, you can run more ignition timing advance. This creates higher efficiency and allows for higher total power.
• Safety Margin: Low compression is more forgiving to variations in fuel quality or heat soak, providing a larger, safer margin of error for tuning

The key takeaway here is that N/A performance engines with high CR and hot cams are not a great candidate for supercharging / forced induction unless resetting the CR to more acceptable levels. 

The issue is then that the raised CR is usually due to decked heads - material that cannot be put back - leaving too little material in the heads to be able to increase the cylinder head volume by material removal.