Skip to content

Porsche 356b super cabrolet vs Porsche 911: reliability comparison

MOT pass rates, common faults and mileage compared from real UK MOT data.

Porsche 356b super cabrolet
50%
MOT pass rate · 1 vehicles
Porsche 911
85%
MOT pass rate · 74,656 vehicles
Verdict: On MOT pass rate the Porsche 356b super cabrolet (50%) and Porsche 911 (85%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Head to head

Measure Porsche 356b super cabrolet Porsche 911
MOT pass rate 50% 85% ✓
MOT failure rate 50% 15% ✓
Faults & advisories per test 0.5 ✓ 1.1
Dangerous-fault share 0% ✓ 1%
Average mileage 11,935 mi 70,982 mi
Sample size (vehicles) 1 74,656

Most common faults

Porsche 356b super cabrolet

  1. Offside Front Subframe mounting prescribed area is fractured (2.4.A.3)

Porsche 911

  1. Nearside Rear Tyre worn close to the legal limit (4.1.E.1)
  2. Offside Rear Tyre worn close to the legal limit (4.1.E.1)
  3. Under-trays fitted obscuring some underside components
  4. Nearside Front Tyre worn close to the legal limit (4.1.E.1)
  5. Offside Front Tyre worn close to the legal limit (4.1.E.1)
  6. Oil leak, but not excessive (8.4.1 (a) (i))

Reliability FAQ

On MOT pass rate the Porsche 356b super cabrolet (50%) and Porsche 911 (85%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Full Porsche 356b super cabrolet report Full Porsche 911 report Most reliable cars

Pass rates are computed over completed (pass/fail) MOT tests. Reliability also depends on age, mileage and upkeep — see each model's page for the full picture.