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Step one was a competition valve job on a Serdi seat cutting machine, including sweeping the chambers out to within .025 inches of the scribed head gasket line. This is where we prefer to begin a serious flow modification effort. Although the MP heads already have a decent valve job, opening the bowls by machine with a 75-degree throat cutter greatly reduces handwork and improves accuracy when carving the bowls, so we recut the seats as part of the process. Port flow to .400 inches was up, although the raw machined throat cut needs to be hand-massaged to finish the job.