Valve Spring Shims, Spacers & Seats

Installing valve springs properly and at the correct height is critical in order for proper engine operation and to maximize performance. If the valve springs are installed too tight, coil bind will result, causing valvetrain failure. If they are installed too loosely, they can cause increased heat that will lead to faster wear and valvetrain part failure as well. JEGS offers cylinder head service parts, including valve spring components, from top manufacturers such as AFR valve spring shims, Moroso, Dart valve spring shims, COMP Cams, JEGS valve spring shims, and more. View our wide selection of valve spring shims, shim spacers, and valve seats that will help complete your next valvetrain project in your street or race engine.

Why Valve Spring Shims, Spacers, And Seats Are Important

When setting up cylinder heads, valve spring installed height is very important. Valve spring shims, spacers, and seats allow the height to be adjusted to the proper specifications. In addition, Valve spring cups and locators aid in keeping the valve springs in the correct position so that they don't walk during use.

Allows You To Set Up Proper Installed Spring Height

If the distance from the base of the valve spring to the bottom of the valve spring retainer is too long, the spring will be too loose and if the distance is too short, coil bind will result. Valve spring shimming with spacers and seats is needed to properly set up the correct spring height and optimize engine performance, ensuring longer valve train life.

Ensures The Valve Spring Is In The Proper Position Throughout The RPM Range

Valve spring cups (with an inside or outside shoulder type) and locators help support and hold the valve spring diameter in place throughout the engine rpm range to ensure proper valvetrain operation. Without these components, the springs can "walk", which will lead to damage or erratic engine performance.

Valve spring shims, spacers, and seats play a very important role in correct valvetrain setup. To help you with your search, below are answers to the most common questions about valve spring shims, spacers, and seats:

What Are Valve Seats?

The cylinder head valve seat is the surface that the intake and exhaust valve rests and seats against when it is closed. When the valve is closed, the valve seat forms a seal around it, which allows combustion pressure to build, resulting in engine power.

How To Check Valve Seats

There are several different visual checks on valve seats that can be performed to confirm their condition. When the valve is closed it should contact the seat all the way around. With the valve springs removed, a good valve can be put into the guide and with a good push, the valve should bounce off of the seat to indicate a good setup. If the valve sticks in the seat or doesn't contact completely around the valve seat, the valve and seat needs attention.

What Are Valve Spring Shims?

Valve spring shims are flat circular discs that are installed under the valve spring to raise its height to the proper level. Valve spring shim kits include shims of varying heights to cover any combination that would be needed to reach the correct valve spring installed height.

How To Determine Valve Spring Shim Thickness

Valve spring shim thickness can be determined with a digital dial caliper or other precision measurement instrument. These tools work by sliding the "fingers" around the thickness of the shim and provide a readout in millimeters or in a decimal format of the height.

Get Your Valve Springs Set Up Correctly With Shims, Spacers, And Seats From JEGS

Valve spring installed height is critical to engine valvetrain operation. If set up incorrectly, damage or poor engine performance will result. Browse our large selection of valve spring shims, spacers, cups, and seats that will help set your cylinder head valve springs to the proper height on your street or race engine.

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