# Cylinder bore diameter by piston size (NA8)

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

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

Confidence: fsm

Cylinder bore
mm {in}
Standard 83.000—83.019 {3.2678—3.2684}
0.25 {0.010} oversize 83.256—83.263 {3.2778—3.2780}
0.50 {0.020} oversize 83.506—83.513 {3.2877—3.2879}

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-diameter-na8",
  "name": "Cylinder bore diameter by piston size (NA8)",
  "aliases": [],
  "applies_to": [
    {
      "gen": "NA",
      "years": [
        1994,
        1997
      ],
      "engines": [
        "BP"
      ],
      "note": "Other years inferred from 1994 factory evidence."
    }
  ],
  "kind": "non-torque",
  "value_text": "Cylinder bore\nmm {in}\nStandard 83.000—83.019 {3.2678—3.2684}\n0.25 {0.010} oversize 83.256—83.263 {3.2778—3.2780}\n0.50 {0.020} oversize 83.506—83.513 {3.2877—3.2879}",
  "procedure": {
    "notes": "Measure X and Y at three axial levels A/B/C in each cylinder. Base reboring on the actual oversize-piston diameter; all cylinders must have the same diameter."
  },
  "confidence": "fsm",
  "sources": [
    {
      "source": "fsm-1994",
      "page": "B–54 (PDF p. 91)",
      "as_printed": "Cylinder bore\nmm {in}\nStandard 83.000—83.019 {3.2678—3.2684}\n0.25 {0.010} oversize 83.256—83.263 {3.2778—3.2780}\n0.50 {0.020} oversize 83.506—83.513 {3.2877—3.2879}",
      "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-diameter-na8/"
}
```