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.
-
Valves are ground (as required) on a Kwik-Way valve grinder which has a spindle chuck TIR at .0005" (.013mm) or less.
-
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
-
German sourced standard, first and second overize guides.
-
Valve seats: Hi-Chrome SAE10b/5 globular perlite and tempered martensite with a uniform dispersion of chromium carbides.
-
Factory BMW valves, springs, collars and retainers. Alternative German or Swiss high quality replacement parts are used when applicable.
Process
-
Heads are inspected, disassembled, hot tank cleaned and again inspected.
-
The heads are media blasted.
-
All critical dimensions and components are again inspected.
-
Valves are ground (as required) on a Kwik-Way valve grinder which has a spindle chuck TIR at .0005" (.013mm) or less.
-
Valve bores (ID & OD) are machined using a precision Sunnen honing machine and tooling.
-
Seats features (both OD and valve interface angles) are processed with all carbide tooling as applicable on a Rottler SG7 machine.
-
​Heads are processed in a commercial ultrasonic cleaner and assembled
