Mechanical improvements in 1959 included increased the engine displacement to 1588 cc (producing 80 bhp) and Lockheed disc brakes in the front. The car could go from 0-60 mph in 14.2 seconds. It registered a top speed of 96.1 mph and a fuel consumption of 29.7 miles per imperial gallon in its first test drive.
The MGA 1600 can be identified by a "1600" on the boot and the cowl grill. Using some leftover special wheels and four-wheel disc brakes a small number of 1600 Deluxe versions were produced.
The exterior of the MGA 1600 is similar to the 1500 with no door handles provided on the outside. It is distinguished by its two tier taillights and a “1600” badge next to the air vents. The grille is a laid-back version of the original that the old T-Series MG hosted. The 1600 also has larger lamps with separate marker and turn signal lamps, something that was not there on the MGA 1500.