Valve Springs

Do your valves float at high rpm, or does a new camshaft need more spring pressure and longer travel? Valve springs keep the valves closed and make sure they follow the cam profile. Here you can choose between single and dual springs for engines that need to handle more than stock.

What valve springs do in your project

The spring has to close the valve quickly enough for it to follow the cam profile. At high rpm or with a camshaft with more lift, stock springs can cause valve float, where the valve can't keep up, and in the worst case this can lead to contact between valve and piston. We offer both dual springs with an inner and an outer spring and single springs from brands such as Brian Crower, Ferrea, COMP Cams, Supertech and GSC Power Division.

How to choose valve springs

• Spring pressure: The pressure with the valve closed and at full lift must match the cam and your rpm target. Too much pressure can increase wear on the camshaft and valvetrain.
• Lift and travel: The spring must handle the cam's lift and still have clearance before the coils bind.
• Engine code: The springs are typically made for specific engines, e.g. Honda K20A2 or Mitsubishi 4G63, and some variants are designed for high-lift camshafts.
• Installed height: This depends on valve length, spring seats and retainers.

Installation and interaction with other parts

The springs work together with retainers, valve locks, spring seats and valves, and dual springs may require different retainers or seats than stock. Check the installed height during assembly, and consider having the spring pressure measured after hard driving, as springs can lose tension over time. If you're switching to a new camshaft, it makes sense to choose springs at the same time.

Frequently asked questions

What is the difference between single and dual springs?

Dual springs have an inner and an outer spring, which typically give more total pressure and some extra safety if one spring fails. Single springs take up less space. The choice depends on camshaft, cylinder head and rpm target.

Do I need to replace valve springs when fitting a new camshaft?

Often yes, if the cam has more lift or will run at higher rpm than stock. Compare the cam manufacturer's recommended spring pressure and lift with the spring data for the specific part number.

How do I detect worn valve springs?

Typical signs are misfires or power loss at high rpm, because the valves don't close in time. The reliable method is to measure spring pressure and installed height with a spring tester and compare with the specification.