Springs: What Do They Really Do? An Insight Into Tuning
We’re going to racing school.
Determine Wheel Rate
If you want to compare spring rates to another car you can’t simply use the lb/in. rating provided by the manufacturer. All cars have particular suspension systems that work springs differently. This is where wheel rate comes in. By dividing the spring rate by something called motion ratio you can come up with a way to universally compare spring across various automotive platforms.
Balance The Car
Springs actually balance the handling characteristics of a car. If you jack up the spring rate in the rear you may begin to induce oversteer where the car was settled before. Conversely, a car that is under sprung will handle like a boat and can be downright dangerous. As your tire grip goes up, the demand a suspension system requires of the spring rate to keep the same balance will increase. It’s always changing depending on grip.
Work in Tandem With Shocks
Springs and shocks go hand in hand. While a springs job is to soak up bumps, the shock's job is to return it back to its original state neither too quickly, nor too slowly. Once reasonable spring rates are determined you will want to use sway bars to fine-tune your setup. Over springing a car without upgrading the shocks is a recipe for disaster. It is also a way to run higher spring rates that don’t feel as harsh.
Help in Weight Reduction
Springs often come in smaller diameters which can mean saving precious pounds to some racers. If you are trying to go for a super lightweight build, do not discount the spring as part of the equation. Having said that, do not buy cheap springs that will eventually sag causing you problems. Opt for high quality if you’re going to reduce weight.
Aero Affects Everything
If you throw effective aerodynamics onto a vehicle, your spring rate will likely need to increase. make up is all well and good on a super smooth race track, but cars that see double duty don’t get the luxury of these glass surface roads. In the real world, we have to deal with bumps that make stiff springs unsafe. Understand that you can’t do both when it comes to high performance and stability on real-world roads. A compromise will ultimately be slower in both environments than chasing a clearly defined goal.
Springs do way more than just keep a car flat in the corners. They also do a lot more than simply lowering a car for a better center of gravity. These are dynamic tuning instruments that makeup just one piece of the tuning puzzle. Understanding the principles of what makes a car fast—sticky tires, aerodynamics, good balance, etc.—will ultimately determine what direction your mods need to go in.
Hope you enjoyed reading.