# Valve head margin thickness (Mazdaspeed)

Canonical URL: https://miatatorque.com/spec/valve-head-margin-msm/

Applicability: NB 2004–2005 (BP-Z3-TURBO) — 2004 factory turbo-engine evidence; 2005 inferred within MSM family.

Confidence: fsm

Margin thickness
IN: 0.9 mm {0.035 in} min.
EX: 1.0 mm {0.039 in} min.

Always confirm against your factory manual. Match every restriction and follow all stages and procedure notes. Disputed claims must not be automatically resolved. The complete record below preserves every printed unit, source claim and procedure.

```json
{
  "id": "valve-head-margin-msm",
  "name": "Valve head margin thickness (Mazdaspeed)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NB",
      "years": [
        2004,
        2005
      ],
      "engines": [
        "BP-Z3-TURBO"
      ],
      "note": "2004 factory turbo-engine evidence; 2005 inferred within MSM family."
    }
  ],
  "kind": "non-torque",
  "value_text": "Margin thickness\nIN: 0.9 mm {0.035 in} min.\nEX: 1.0 mm {0.039 in} min.",
  "procedure": {
    "notes": "Measure each valve margin; replace as necessary."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "workshop-bp-turbo-2004",
      "page": "01–10–18 (PDF p. 30)",
      "as_printed": "Margin thickness\nIN: 0.9 mm {0.035 in} min.\nEX: 1.0 mm {0.039 in} min.",
      "verified_years": [
        2004,
        2004
      ],
      "document": {
        "id": "workshop-bp-turbo-2004",
        "tier": 1,
        "title": "2004 Mazda Engine Workshop Manual BP (1.8L), normally aspirated and turbo",
        "part_number": "9999-95-EWBP-04",
        "covers": [
          {
            "gen": "NB",
            "years": [
              2004,
              2004
            ],
            "engines": [
              "BP-Z3-TURBO"
            ],
            "trans": [
              "6MT"
            ]
          }
        ]
      }
    }
  ],
  "jobs": [],
  "system": "engine",
  "component": "inventory-pass-2026-10",
  "componentName": "Service measurements and fasteners",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/valve-head-margin-msm/"
}
```