Why does the 4G63 need Rocker Retainers?Updated 18 minutes ago

The Mitsubishi 4G63 is a tough engine, but its rocker arms rely on valve spring pressure to stay in place. When that pressure is lost for a split second, the rocker can move out of position and cause serious engine damage.

When it happens

• A misfire
• An over-rev, such as a missed shift
• Hitting the rev limiter hard
• Pushing higher RPM than the valvetrain is set up for

The more power and RPM you run, the more it matters.

What the clips do

Our heat-treated high-carbon steel clips are designed to catch each rocker during those unexpected valve events and hold it in place until valve spring pressure is regained, reducing the risk of a dropped rocker. They're a safety net on the street and at the track, and much cheaper than rebuilding an engine. A severe over-rev can still break them.

They don't replace a good valvetrain setup. You still need valve springs, a cam and a rev limit that suit your build.

Choosing a kit? See Which 4G63 Rocker Retainer kit do I need?