# How do you calculate spring rate for active coils?

## How do you calculate spring rate for active coils?

The way to determine the total amount of active coils your spring has is to divide the body length (length of spring without the hooks), divide it by the wire diameter, and subtract one coil.

What is the unit for spring rate?

N/m
The unit of measurements of spring rate is N/m or Ibf/in i.e. force divided by distance. The spring rate of a spring is the change in the force applied divided by the change in diversion of the spring.

How do you calculate combined spring rate?

(Identical Spring Rates) You have two identical springs with a spring rate of 30 lbf/in (pounds of force per inch). To calculate the rate these two provide together, simply multiply the rate by 1/2 (0.5).

### How do you choose a spring rate?

When attempting to determine the correct spring rate for a car, the trick is to set the ride height so the chassis rests in the shocks’ sweet spot within this small 3- to 4-inch window. A solid-axle rear suspension, on the other hand, is a bit more forgiving.

How can I make my coil spring stronger?

If you make the wire diameter larger, you will make the spring stronger and if you make it smaller, you will make it weaker. This is because, by making the wire diameter larger, you are also making the spring’s coils tighter which reduces the spring index.

What should the spring rate be on a coilover?

The angle that the coilover assembly is installed at has a large effect on what the spring rate will need to be. The greater the angle of the spring, the stiffer it will need to be to support the weight of the car. A coilover with a 10” 225 lb. spring that is installed at 0° straight up and down (90° from the axle centerline) will support 1450 lbs.

#### Is it OK to use music wire springs?

Music wire springs can withstand high load stresses compared to other materials, which makes this material best suited for cyclic applications. Music wire is cold drawn. Although this material is versatile, it’s not recommended for service temperatures above 250°F (121°C). M & S Spring Company’s music wire springs meet ASTM A228 standards.

Which is the toughest spring wire to use?

Music wire (cold drawn) is a high carbon spring steel that has uniform, high tensile and the ability to withstand high stress under repetitive loading. Considered the toughest of spring materials, music wire also offers an excellent surface finish.

How are spring lengths determined for coil over systems?

Spring lengths have been determined by the application, so you just have to choose the rate. While we provide many options, determining your vehicle weight can direct you to the right one. Once your front end weight has been calculated, simply choose the suggested spring rate. For a larger version, see our Spring Rate Chart & Vehicle Weight Sheet.