Valve Locks

Valve Locks: the small keepers that hold your whole valvetrain together

Valve locks - also called keepers or collets - are the pair of small tapered wedges that lock the retainer to the valve stem. They sit in the machined groove near the tip of the stem, and the spring load clamps them tight so the retainer, spring and valve all move as one unit. Get them wrong and the valve drops into the cylinder, so this is a part you replace with clean, matched, undamaged pieces every time the head comes apart.

People fit fresh valve locks when they upgrade springs and retainers, convert between groove styles, or need a slightly taller lock to reset installed height on a built head.

What ThreePiece stocks

We carry 27 valve lock sets in the Engine Components section, priced from $29 to $179 - that's the current range for what's in stock, not a fixed promise. Three brands are represented: Supertech makes up the bulk of the range with 19 sets, followed by Ferrea with 5 and Manley Performance with 3. Product names cover Toyota, Honda, BMW, Nissan, Mitsubishi, Acura, Mazda and Audi applications.

How to choose

Start with the numbers that must match your valves: stem size (5mm, 5.5mm, 5/16), lock angle (6 or 7 degrees), and groove style. A single-groove conversion set only works if your valves and retainers are cut for a single groove; radial and machined-bead styles behave differently under load. Some sets require two locks per valve - check the set count against your valve count so you order enough. Taller locks exist to adjust installed height, so pick those deliberately, not by accident. Match the lock angle to the retainer angle, and buy the whole valvetrain group from one plan rather than mixing styles.

What else you need

Valve locks are one piece of a head refresh. When you're this deep, look at Head Gaskets and full Gasket Kits so the head reseals properly. If the short block is coming apart too, the Pistons and Bearings pages cover the rotating assembly. Browse the wider Engine Components section for anything else the build needs.

Fitment and ordering

Fitment data is present on 3 of these sets, sampling Mazda Miata, Nissan 240SX and Mitsubishi Lancer Evolution across a 1991-2015 range - treat that as a sample, not the full list. If you're unsure which lock your head takes, call our fitment line at 813-535-5801 or reach us through Contact Us before you order. Every order ships with free shipping, and Affirm and Katapult financing is available at checkout.

Valve Locks: the small keepers that hold your whole valvetrain together

Valve locks - also called keepers or collets - are the pair of small tapered wedges that lock the retainer to the valve stem. They sit in the machined groove near the tip of the stem, and the spring load clamps them tight so the retainer, spring and valve all move as one unit. Get them wrong and the valve drops into the cylinder, so this is a part you replace with clean, matched, undamaged pieces every time the head comes apart.

People fit fresh valve locks when they upgrade springs and retainers, convert between groove styles, or need a slightly taller lock to reset installed height on a built head.

What ThreePiece stocks

We carry 27 valve lock sets in the Engine Components section, priced from $29 to $179 - that's the current range for what's in stock, not a fixed promise. Three brands are represented: Supertech makes up the bulk of the range with 19 sets, followed by Ferrea with 5 and Manley Performance with 3. Product names cover Toyota, Honda, BMW, Nissan, Mitsubishi, Acura, Mazda and Audi applications.

How to choose

Start with the numbers that must match your valves: stem size (5mm, 5.5mm, 5/16), lock angle (6 or 7 degrees), and groove style. A single-groove conversion set only works if your valves and retainers are cut for a single groove; radial and machined-bead styles behave differently under load. Some sets require two locks per valve - check the set count against your valve count so you order enough. Taller locks exist to adjust installed height, so pick those deliberately, not by accident. Match the lock angle to the retainer angle, and buy the whole valvetrain group from one plan rather than mixing styles.

What else you need

Valve locks are one piece of a head refresh. When you're this deep, look at Head Gaskets and full Gasket Kits so the head reseals properly. If the short block is coming apart too, the Pistons and Bearings pages cover the rotating assembly. Browse the wider Engine Components section for anything else the build needs.

Fitment and ordering

Fitment data is present on 3 of these sets, sampling Mazda Miata, Nissan 240SX and Mitsubishi Lancer Evolution across a 1991-2015 range - treat that as a sample, not the full list. If you're unsure which lock your head takes, call our fitment line at 813-535-5801 or reach us through Contact Us before you order. Every order ships with free shipping, and Affirm and Katapult financing is available at checkout.