Performance Racing Valve Springs & Kits

When selecting a performance camshaft, the valve springs need to match for proper operation, as too strong of springs will prematurely wear the lobes on the cam and too light of springs will cause valve float, creating a popping sound in the engine at higher rpms. The camshaft manufacturer provides the recommended valve springs, retainers, and locks / keepers to help with valve spring selection.

Performance spring kits are made from much stronger materials than factory springs. This allows for heavier-duty use and racing applications where the springs experience greater pressures and cycles without breaking.

Valve springs (sometimes called "race springs" or "speed springs" in performance racing applications) lift the intake and exhaust valves until they seal into the cylinder head valve seats. Springs connect to the valves by using keepers or locks that fit into the grooves at the top of the valve and the retainers that are installed at the top of the valves, providing tension to keep the valve assembly together. When pressure is applied to the valve stem tip from the rocker arm, the valve spring compresses. The valve spring keeps the valvetrain components from getting loose as it pulls the valve up into the seat and pushes against the rocker arm, which creates tension between the pushrod and camshaft lifters against the cam lobes. It is important to match valve springs to the camshaft requirements as too strong of springs will cause excessive cam lobe wear and too weak of springs will create valve float.

There are several different types of performance valve springs commonly found in performance V8 applications (example lifts and camshaft types below are referenced for SBC applications):

One way to remove valve springs without a valve spring compressor is with a deep well socket, socket extension and a mallet. The socket outside diameter needs to be as close to the outside diameter of the valve spring retainer as possible. With the extension connected to the deep socket and centered over the valve spring retainer, give it a few light-to-medium taps to help loosen the retainer from the keepers / locks. Then hit the valve spring retainer firmly. If done correctly, the retainer will compress the valve spring enough that the keepers / locks fall out of place. This will allow you to remove the locks, retainer, and valve spring. Use special care to ensure the socket doesn't walk off the retainer as damage to the components, including the valves, can result.

Depending on the engine application, the steps on how to replace valve springs will change. However, for most older V8 domestic engine applications there are two processes, depending on if the cylinder heads are installed on the block or not. For cylinder heads bolted to the engine block, air pressure needs to be applied into the head through the spark plug hole, creating pressure that will keep the valve from dropping into the cylinder. This can be accomplished with an air hold fitting hose. A stud mounted valve spring compressor is then needed for valve spring installation as leverage is applied to the valve spring from the rocker arm stud. If the cylinder head is off the block, a clamp spring compressor is needed to squeeze the spring during installation, clamping around the cylinder head. Before spring installation, the installed height of the spring has to be confirmed, which is advertised with the valve spring kit you choose. A spring height micrometer will help confirm that you have the correct spring height by putting it in place of the valve spring first. If needed, a valve spring shim kit will help you to reach the correct valve spring height by adding enough shims between the valve spring seat and the lower retainer using the spring height micrometer. Once the number of shims and height is established with the keepers and upper/lower retainers in place, the spring height micrometer can be removed. Next, the valve spring can be set in place with the appropriate shims and retainers. Then, using the appropriate valve spring compressor, squeeze the spring enough that the retainer can lay on top of the springs and the valve locks / keepers can be put into the valve stem grooves. Finally, slowly release the compressor and confirm that the retainer and keepers are properly seated, holding the valve assembly in place.