The clearance volume refers to the distance from the top of the piston flat to the block deck of the engine cylinder. In many engines the piston will not come all the way to the cylinder block, but there is a gap and this gap is the clearance volume. The clearance volume is important to the compression ratio. The compression ratio is the amount of volume that can be compressed in the engine per one unit of space.
Things You'll Need
- Bridge and dial indicator
- Bore gauge
Set the dial of a bridge and dial indicator to zero. A bridge and dial indicator is a type of bridging pit gauge that measure buckles, dents and length of gaps. Place the bridge and dial indicator at the top, dead center of the piston. Read and record the measurement of the piston deck height, which is the gap found just above the piston. The unit of this measurement is inches.
Measure the bore with a bore gauge. A bore gauge is a tool that measures the size of holes, in this case the bore or top hole in the cylinder. Multiply the bore measurement by two.
Calculate clearance volume. Multiple the bore measurement squared by the deck height and the result by the constant 0.7853982. For example, if the bore measurement is 8 inches and the deck height is 0.02 inches, then the clearance volume equals 1.0053 cubic inches: 0.7853982 (8^2) 0.02.
- Photo Credit cylindre et piston image by Unclesam from Fotolia.com
The Compression Ratio for Dished Pistons in a Chevy 350
Engine pistons are available with three basic designs, domed, flat-top and dished. Dished piston tops have the effect of lowering the compression...
How to Calculate Stroke Volume
Stroke volume is the amount of blood ejected from the left ventricle of the heart during contraction. It usually measures between 60...
- How to Calculate the Volume of a Truck Trailer
How to Calculate Pushrod Length
Modern automotive and lubricant technology has created engines that barely need to be touched, except for oil changes. A certain breed of...
How to Calculate a Compression Ratio
In the most basic sense, compression ratio is the simply the volume of an engine's cylinder with the piston at the bottom...
How to Measure Engine Block Height
When working on an engine, it is important to know the engine block's height so that you know what size parts will...
How to Measure & Calculate Creatinine Clearance
Creatinine clearance is a way for doctors to check if the kidneys are working properly. Some medications are processed out of the...