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Cars

Mercedes-AMG A 45 S

Mercedes-AMG states a 270 km/h governor for the A 45 S 4MATIC+. evo and Carscoops print 168 mph for that same limit.

Also known as A 45 S, A45 S
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Top speed

Published as 270 km/hPublished as 270 km/hPublished as 270 km/h

Manufacturer claim and governor for the W177 Mercedes-AMG A 45 S 4MATIC+ (421 PS). The brochure states 270 km/h. evo prints 168 mph and Carscoops prints 270 km/h (168 mph); 270 km/h is 167.8 mph, so 167 and 168 are the same rounding. The base A 45 limiter of 250 km/h is not stored.

ClaimedMercedes-AMG (opens source in a new tab)

In context

  • 2.6× a cheetah's timed top speedSourced · Cheetah, 29 m/s. Sharp 1997, mean of three timed runs over 201.2 m
  • A football field in 1.2 sConstant · American football field, 100 yd (91.44 m)
  • London to New York in 20 h 38 minConstant · London to New York, 5,570 km great-circle

Worked out from the sourced figure above, which stays the ranked number.

This list

Why it's so fast

A car is fast when the force pushing it forward still beats the air, and when the tires and the gearing can use that force. A limiter is a different fact from an unlimited run.

  1. Drag and gearing

    Top speed is the balance point: thrust equals aerodynamic drag. The gearing has to still be pulling when the car gets there, or the engine falls off its power.

  2. What the sources signed

    A manufacturer claim, a magazine test and an electronic governor are not interchangeable. The measurement line says which one this page ranked.

A limited example is the Bugatti Chiron.

This is how the category works. A note written for this entry appears here once it is in the database.

Provenance

Every measurement

Claimed, measured and official figures side by side, each with its source. The ranked figure is marked.

  1. 270km/h168mph75.0m/s146knRanked figure

    Manufacturer claim and governor for the W177 Mercedes-AMG A 45 S 4MATIC+ (421 PS). The brochure states 270 km/h. evo prints 168 mph and Carscoops prints 270 km/h (168 mph); 270 km/h is 167.8 mph, so 167 and 168 are the same rounding. The base A 45 limiter of 250 km/h is not stored.

    Claimed
    Mercedes-AMG (opens source in a new tab)

Reference

Specs

Model
W177 A 45 S 4MATIC+, 421 PS
Layout
All-wheel-drive hatchback
Limiter
Governor, 270 km/h

Spot a wrong number?

Every report is read by a person, and corrections are dated on the page.