Valve Seat & Guide Equipment Selection - Engine Builder Magazine

Valve Seat & Guide Equipment Selection

Cylinder head work is one of the mainstays of any engine building operation, and these components often require valve guide and seat work to restore them for service or to improve performance. In order for a valve to seat correctly, for efficiency and power, engine builders must replace or bring back to spec all valve seats and guides.

Seats that are cracked, loose, sunken or destroyed in some manner must be replaced with new. Drilling, reaming, replacing valve guides, removing worn, loose or damaged valve seats, cutting new seat counterbores and machining valve seats are all part of the reconditioning process that your shop must be able to handle as efficiently as possible and with precision and accuracy.

There are a few different kinds of seat and guide machines available today to fit most budgets. The first kind of machine is not much more complex than a drill press and is often referred to as such. In these seat and guide machines the tooling sets in a solid column and the table floats to move from guide-to-guide. These are very basic seat and guide machines that have some limitations compared to more advanced machines, however, there are still some small shops and hobbyists that use this style of machine. A small shop may not be able to justify the larger, more expensive machines, and many of these small shops simply don’t have the volume to be concerned about doing hand grinding and lapping.

The second level of seat and guide machines is the floating powerhead system. These machines have become the industry-standard for many engine builders today. This equipment, according to the manufacurers we surveyed for this article, run in the price range of about $18,000-$30,000, depending on the options and manufacturer you choose. On these machines, the cylinder head is stationary underneath a floating powerhead. The powerhead floats above on flat ways that adjust front-to-back and side-to-side.

The powerhead weighs much less than the cylinder heads, so when you center the powerhead, a procedure similar on most models, it floats and centers with the pilot. Once it is centered over the pilot, you let off the foot pedal to lock it in place. This setup gives you a very rigid platform.

Modern cylinder heads often have canted valves so on an older-style machine you have to tilt the fixture to machine canted valve seats and guides. The fixture is relocated and set for each guide. When using a modern seat and guide machine, the powerhead tilts, allowing you to adjust the powerhead for whatever angle you need. Once you’ve set the powerhead angle you can go up and down the line with the same tilt angle for each valve seat. Some machines can accommodate up to 15 degrees of rotating tilt.

Today’s valve seat and guide machines also use three-blade carbide cutters with three-angles or more. These cutters, or form tools, give you a very consistent profile and concentricity because the profile is built into the tooling. Manufacturers vary with the type of tooling each offers,  but all are essentially a form tool with built-in angles.

The third style seat and guide machine is the “live pilot” design. Whereas a “dead pilot” design remains stationary in the guide as the tooling rotates, a live pilot spins with the tooling in the guide. You have to be very precise when fitting live pilots into guides otherwise too much play could result in a seat that isn’t completely round. Some live pilot machines have a single blade carbide cutter that can adjust while it spins to create almost an infinite number of profiles.


The Equipment:

Rottler SG8

Standard Equipment:

Electronic Level Built-in, 360 Deg. Cradle,

Toolbox, Vacuum Tester  Built-in


One-year on machine and tooling

Spindle Diameter:

3.150?, 80mm

Maximum Tilt (either side of zero):


Maximum Cylinder Head Length (with diesel fixture):

50?, 1270mm


25?L x 53?W x 80?H


2,800 Lbs.

Voltage Requirements:

208/208/ 220-volt, single phase, 15 amp

Company: Rottler Manufacturing

Phone: 800-452-0534


Email: [email protected]


Sunnen VGS-20

Standard Tooling:

Universal 360 Rollover Fixture, Tool Storage Rack, Built-in Cabinet




Fast, easy installation of valve guide inserts; Spot facing of valve guides and bosses; Cuts valve insert pockets (aluminum or cast iron); Simultaneous multi-angle cutting of valve seats; Drilling and tapping for threaded studs or removal of broken exhaust studs; Bronze guide liner installation and reaming

Company: Sunnen Products Company

Phone: 800-772-2878


Email: [email protected]


Peterson TCMV/25

Standard Tooling:

• Levels

• Metric wrench set with hex keys

• 3-angle insert tooling

• Insert-cutters (carbide)

• Drill chuck (#3 Morse Taper)

• Dead pilot system

• Drills and reamers




• Variable speed spindle

• Digital RPM readout display

• 360-degree rotation air table

• Rugged, heavy duty column

Company: Peterson Machine Tool

Phone: 800-255-6308


Email: [email protected] 


Winona Van Norman VSG4720


90? L x 34? W x 77? H


1,980 Lbs.

Standard Tooling:

818084 Tooling Package, Fast Mount Bar, Head Mount Plate, Hex Key Set, Standard, Electronic Level .01 deg. Res., Leveling Pads, Adapter, Alignment Rod, Canted Valve Alignment Bar




Boring Head Tilt 15 deg. (30 Total), Serdi Style Spindle Taper, Air Float Boring Head, Hydraulic Boring Head Clamping System, Fine Feed for precision machining

Company: Winona Van Norman

Phone: 316-219-3500


Email: [email protected] 


Newen Fixed-Turning(R) Contour-BB(TM)

Electrical Requirements:

220-240V/20 Amps/1 Phase/ 50/60 Hz

Spindle Motor:

1.5 KW

Spindle Speed:

120-3,000 rpm

Spindle Tilt (Rotation):



One single tool to machine any profile, any valve seat diameter, any valve seat material … All FIXED-TURNING® machines allow machining as small as one hundredth of a millimeter (.00039?) on an entire profile, regardless of its length, while providing perfect geometry of the seat (circularity, angle, concentricity). The numerical control automates depth adjustments within + or – .01mm or .00039?

Company: NEWEN

Phone: 800-639-3693


Email: [email protected] 


Serdi 100 HD

The new SERDI 100 HD has a combination workhead on double air cushion, equipped with an upgraded high-torque spindle, which is operated by a 2.2kw motor, and a highly rigid bed that can carry heavy cylinder heads with an easy travel front to back on air cushion table and pneumatic clamping. This new model is 216 percent more powerful than the previous Serdi 100 heavy duty model.

Company: Serdi Corporation

Phone: 800-447-3790


Email: [email protected]


T&S Machine The System 2000XL

T & S Machine’s System 2000 cylinder head center is a machine that can handle all of the your shop’s cylinder head work, whether your work is general automotive, high performance, or diesel. The System 2000 is simple, versatile, rugged and fast. Offered with one of the most complete tooling packages in the industry.

Company: T & S Machines and Tools

Phone: 800-766-2069


Email: [email protected]

To find more information about these and other Valve Guide and Seat Machines, click on the Buyers Guide tab for more manufacturers of this type of equipment.rottler sg8sunnen vgs-20peterson tcmv/25winona van norman vsg4720newen fixed-turning, contour-bbserdi 100 hdT&S Machine The System 2000XL

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