01/09/2026
Ready for fitting.
Stage 3, clubman head, unleaded.
New inlets valves race spec, 35.7mm.
New exhaust valves race spec, 29.5mm.
New tapered bronze guides and Viton stem seals.
New double valve springs.
New unleaded seats.
Combustion chambers polished.
3 angle valve seat cut.
Inlet & exhaust ports, ported.
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