# Cylinder bore taper (NA8)

Canonical URL: https://miatatorque.com/spec/cylinder-bore-taper-na8/

Applicability: NA 1994–1997 (BP) — Other years inferred from 1994 factory evidence.

Confidence: fsm

Taper: 0.019mm {0.0007 in} max.

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": "cylinder-bore-taper-na8",
  "name": "Cylinder bore taper (NA8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "note": "Other years inferred from 1994 factory evidence."
    }
  ],
  "kind": "non-torque",
  "value_text": "Taper: 0.019mm {0.0007 in} max.",
  "procedure": {
    "notes": "Difference between top and bottom factory measurement levels A and C; rebore oversize if excessive."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "B–54 (PDF p. 91)",
      "as_printed": "Taper: 0.019mm {0.0007 in} max.",
      "verified_years": [
        1994,
        1994
      ],
      "document": {
        "id": "fsm-1994",
        "tier": 1,
        "title": "1994 Mazda MX-5 Miata Workshop Manual",
        "covers": [
          {
            "gen": "NA",
            "years": [
              1994,
              1997
            ],
            "engines": [
              "BP"
            ]
          }
        ],
        "note": "Mazda's base manual for 1994–97; later model years got supplements, which we haven't checked yet."
      }
    }
  ],
  "jobs": [],
  "system": "engine",
  "component": "inventory-pass-2026-10",
  "componentName": "Service measurements and fasteners",
  "sequence_diagrams": [],
  "url": "https://miatatorque.com/spec/cylinder-bore-taper-na8/"
}
```