{
  "factory_source": "https://www.spridgets.de/downloads/Midget%201500%20WH%20Teil%201.pdf#page=13",
  "factory_read": "Accessible AKM4071/B part1 PDF13/printed04-3 visually read. Seven effective coils,9.85in/25cm free length,7.08in/18cm at750+/-15lb and printed337+/-6.8kg. No fitted spring or installed load identified.",
  "factory_recorded_not_applied": {
    "effective_coils": 7,
    "free_length_in_mm": [
      9.85,
      250
    ],
    "test_length_in_mm": [
      7.08,
      180
    ],
    "load_lb_kg": [
      750,
      337
    ],
    "load_tolerance_lb_kg": [
      15,
      6.8
    ],
    "spring_rate_printed_imperial": "271 lbf/in",
    "metric_rate_status": "Scan unit/value is ambiguous; not used for a calculated spring rate."
  },
  "supplier": "https://www.mgocspares.co.uk/blog/1320/levelling-up",
  "supplier_read": "CHA129 throughGAN6-171477:4.12in coil diameter,.5in wire,9.85in free length; CHA570 from171478: same listed diameters,10.43in free length. Neither is identified as fitted. Diameter header does not say mean/OD; OD interpretation is conditional, corroborated by photo proportions and the same article\u2019s explicit105mm OD for lowered Midget springs.",
  "supplier_photos": [
    "https://www.mgocspares.co.uk/ImageHandler/109054w1000h1000/CHA129?sequence=109054&width=1000&height=1000",
    "https://www.mgocspares.co.uk/ImageHandler/109055w1000h1000/CHA570?sequence=109055&width=1000&height=1000"
  ],
  "photo_read": "Both visually read; reduced-pitch, ground end treatment. No independent installed coil identity or exact end count/phase measured.",
  "end_count_source": "https://www.leespring.com/spring-coil-count",
  "end_count_scope": "Manufacturer generic rule: closed/ground compression-spring ends contribute two inactive turns. Used for a9-turn comparison, not proof of this car\u2019s effective count/stiffness.",
  "nodes": {
    "left": {
      "limits": "Factory AKM4071/B part1 PDF13/printed04-3 lists7 effective coils,9.85in/25cm free length and7.08in/18cm at750+/-15lb (printed337+/-6.8kg). These are documentary test values, not actual installed length/load. Inch/metric pairs are rounded/inconsistent; no spring rate or preload is inferred. MGOC lists CHA129 throughGAN6-171477 and CHA570 from171478 with .5in wire and4.12in coil diameter; the latter is interpreted as OD, consistent with supplier photos and its105mm-OD lowered-spring discussion, not explicitly headed OD in the table. Neither fitted variant is selected. Supplier photos show closed/ground ends; generic Lee Spring counting gives2 inactive end coils for that form. Seven central turns plus2 modeled end turns is an estimated9-turn comparison, not independently verified effective/total count or working stiffness. End-rise12.9mm, pitch transition, phase/hand, grinding and axial245.533mm display height are construction estimates. Original spring axes and old centerline Y endpoints become the new ground-plane bounds; no body/suspension part is moved to force seating. Current spring/seat gaps are source registration differences, not fitted clearance, load, spring restraint, travel or verified replacement path.",
      "supplier_wire_diameter_mm": 12.7,
      "supplier_coil_diameter_in": 4.12,
      "interpreted_outside_diameter_mm": 104.648,
      "derived_mean_radius_mm": 45.974,
      "factory_effective_coils_recorded": 7,
      "estimated_display_central_end_total_turns": [
        7,
        2,
        9
      ],
      "estimated_end_rise_mm": 12.899999999999999,
      "estimated_center_pitch_mm": 31.390476190476193,
      "estimated_end_start_pitch_mm": 10.845502645502643,
      "retained_axis_xz_mm": [
        381.00000000000006,
        1016.0
      ],
      "historical_centerline_now_ground_y_bounds_mm": [
        254.0,
        499.5333333333333
      ],
      "estimated_lower_seat_plane_y_mm": 234.5266666666667,
      "reference_lower_ground_plane_to_seat_difference_mm": 19.4733333333333,
      "reference_upper_seat_to_ground_plane_difference_mm": 9.31333333333339,
      "owner_dimensions_applied": false
    },
    "right": {
      "limits": "Factory AKM4071/B part1 PDF13/printed04-3 lists7 effective coils,9.85in/25cm free length and7.08in/18cm at750+/-15lb (printed337+/-6.8kg). These are documentary test values, not actual installed length/load. Inch/metric pairs are rounded/inconsistent; no spring rate or preload is inferred. MGOC lists CHA129 throughGAN6-171477 and CHA570 from171478 with .5in wire and4.12in coil diameter; the latter is interpreted as OD, consistent with supplier photos and its105mm-OD lowered-spring discussion, not explicitly headed OD in the table. Neither fitted variant is selected. Supplier photos show closed/ground ends; generic Lee Spring counting gives2 inactive end coils for that form. Seven central turns plus2 modeled end turns is an estimated9-turn comparison, not independently verified effective/total count or working stiffness. End-rise12.9mm, pitch transition, phase/hand, grinding and axial245.533mm display height are construction estimates. Original spring axes and old centerline Y endpoints become the new ground-plane bounds; no body/suspension part is moved to force seating. Current spring/seat gaps are source registration differences, not fitted clearance, load, spring restraint, travel or verified replacement path.",
      "supplier_wire_diameter_mm": 12.7,
      "supplier_coil_diameter_in": 4.12,
      "interpreted_outside_diameter_mm": 104.648,
      "derived_mean_radius_mm": 45.974,
      "factory_effective_coils_recorded": 7,
      "estimated_display_central_end_total_turns": [
        7,
        2,
        9
      ],
      "estimated_end_rise_mm": 12.899999999999999,
      "estimated_center_pitch_mm": 31.390476190476193,
      "estimated_end_start_pitch_mm": 10.845502645502643,
      "retained_axis_xz_mm": [
        -381.00000000000006,
        1016.0
      ],
      "historical_centerline_now_ground_y_bounds_mm": [
        254.0,
        499.5333333333333
      ],
      "estimated_lower_seat_plane_y_mm": 234.5266666666667,
      "reference_lower_ground_plane_to_seat_difference_mm": 19.4733333333333,
      "reference_upper_seat_to_ground_plane_difference_mm": 9.31333333333339,
      "owner_dimensions_applied": false
    }
  },
  "limits": "Factory AKM4071/B part1 PDF13/printed04-3 lists7 effective coils,9.85in/25cm free length and7.08in/18cm at750+/-15lb (printed337+/-6.8kg). These are documentary test values, not actual installed length/load. Inch/metric pairs are rounded/inconsistent; no spring rate or preload is inferred. MGOC lists CHA129 throughGAN6-171477 and CHA570 from171478 with .5in wire and4.12in coil diameter; the latter is interpreted as OD, consistent with supplier photos and its105mm-OD lowered-spring discussion, not explicitly headed OD in the table. Neither fitted variant is selected. Supplier photos show closed/ground ends; generic Lee Spring counting gives2 inactive end coils for that form. Seven central turns plus2 modeled end turns is an estimated9-turn comparison, not independently verified effective/total count or working stiffness. End-rise12.9mm, pitch transition, phase/hand, grinding and axial245.533mm display height are construction estimates. Original spring axes and old centerline Y endpoints become the new ground-plane bounds; no body/suspension part is moved to force seating. Current spring/seat gaps are source registration differences, not fitted clearance, load, spring restraint, travel or verified replacement path.",
  "owner_measurements_applied": false,
  "workshop": "No safe support, spring-release procedure, compression load, fitted clearance, torque or verified removal path supplied."
}