Rod Ratio Calculator


What is Rod Ratio Calculator?

The Rod Ratio Calculator allows you to calculate an engine’s rod ratio. The rod ratio measures the length of the connecting rod in relation to the stroke of a crankshaft. This parameter is critical in engine design and can have a significant impact on engine performance, efficiency, durability, and other important parameters.


It is easy to calculate the rod ratio using this formula:

Rod Ratio (RR) = Piston Rod Length (PR) / Crankshaft Stroke (CS)

The distance between the center point of the piston pin (TDC) and the big end of a connecting rod is called the length of the piston rod. The distance that the piston travels between top dead center (TDC), and bottom dead center is called the crankshaft stroke.

If the length of the piston rod is 5 inches and crankshaft stroke 3 inches, then the rod ratio would be:

RR = 5. / 3. = 1.67

Calculating the Price

Simply enter the length of the piston rod and the crankshaft stroke values into the input fields, and then click on the “Calculate”. In the output field, you will see the result.


What is the best rod ratio?

The ideal rod ratio is between 1.5 and 1. A higher rod ratio will improve engine efficiency and reduce piston loading. Conversely, a lower rod number can increase engine torque or horsepower.

What does the rod ratio have to do with engine performance?

The engine’s performance is affected by the rod ratio. It has an impact on engine power output, efficiency, durability, and longevity. A higher rod ratio can increase combustion efficiency, decrease piston side loading, and increase engine’s maximum RPM. It can increase the stress on the piston pin and connecting rod. While a lower rod ratio can increase engine torque, horsepower, and decrease combustion efficiency, it can also increase piston side loading and reduce combustion efficiency.

Can the rod ratio be altered?

The length of the connecting rod is a measure of the engine’s rod ratio. This stroke and length are both fixed parameters in most engine designs. It is possible to alter the rod ratio with custom connecting rods of different lengths and/or a modified crankshaft stroke. This is a complicated and costly process that will require careful engineering and testing.


  • Team Your Calculator Home

    We are a team of experts from different fields working on with the motto effortless compute. Our team comprises experienced professionals from various fields, including finance, health and fitness, mathematics, physics, time, biology, chemistry, and more. We are trying our best to provide effortless computing with accuracy. We started only to help people of every field who are facing trouble with calculators. We are trying our best to make easy to use calculators which can be used by school going child to professionals of every field. If you have any questions, suggestions, or concerns, please feel free to contact us on [email protected]

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *