Cylinder Head Restoration

 

Pre-70 BMW Heads

Materials

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Guides: Custom machined Ampco 45. Valve guide ID and OD diameters are concentric with .0005" (.013mm) TIR. Shown below are custom R69/R69S and R50/R60 valve guides.

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Valve seats: Hi-Chrome SAE10b/5 globular perlite and tempered martensite with a uniform dispersion of chromium carbides.

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German sourced valves, springs, collars and retainers. Alternative German or Swiss high quality replacement parts are used when applicable.

Process

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Heads are inspected, disassembled, hot tank cleaned and again inspected.

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The heads are media blasted.

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All critical dimensions and components are again inspected.

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Valves are ground (as required) on a Kwik-Way valve grinder which has a spindle chuck TIR at .0005" (.013mm) or less.

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Valve bores (ID & OD) are machined using a precision Sunnen honing machine and tooling.

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Seats features (both OD and valve interface angles) are processed with all carbide tooling as applicable ona Rottler SG7 machine

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Heads are processed in a commercial ultrasonic cleaner and assembled

 

 

Post-70 BMW Heads

Materials

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German sourced standard, first and second overize guides.

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Valve seats: Hi-Chrome SAE10b/5 globular perlite and tempered martensite with a uniform dispersion of chromium carbides.

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Factory BMW valves, springs, collars and retainers. Alternative German or Swiss high quality replacement parts are used when applicable.

Process

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Heads are inspected, disassembled, hot tank cleaned and again inspected.

bullet

The heads are media blasted.

bullet

All critical dimensions and components are again inspected.

bullet

Valves are ground (as required) on a Kwik-Way valve grinder which has a spindle chuck TIR at .0005" (.013mm) or less.

bullet

Valve bores (ID & OD) are machined using a precision Sunnen honing machine and tooling.

bullet

Seats features (both OD and valve interface angles) are processed with all carbide tooling as applicable on a Rottler SG7 machine.

bullet

Heads are processed in a commercial ultrasonic cleaner and assembled

 

Equipment List

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Rottler SG7 Seat & Guide Machine

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Sunnen MBB-1660-D Honing Machine

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Kwik-Way CV1397 Valve Grinder

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Rockwell 21-100 Milling Machines

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South Bend 9" Model A Custom Built Lathe

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Miller Mig and Tig Welders for fin and thread repair

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Metrology Equipment: Sunnen, Starrett, Mahr, Mitutoyo, and others.

E-mail for more info

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