[2][3] Unlike the 1100 E it replaced, the 103 had a modern four-door saloon pontoon body topping new unibody construction, both pioneered in Fiat's range by the 1950 1400.

Updated as type 103.000, the 1,089 cc (66 cu in) overhead valve four-cylinder was fed by a single Solex or Weber downdraught carburettor, and put out 36 PS CUNA (26 kW) at 4,400 rpm—just one horsepower more than on the 1100 E.[3] The 4-speed manual transmission had synchromesh on the top three speeds and a column-mounted shifter, fashionable at the time.

The former was only available in a grey-brown paint colour, had separate front seats instead of a bench, reduced, non-chromed exterior trim, and lacked a heater and ventilation.

[citation needed] A distinguishing feature of 103s throughout the 1950s were the doors, both hinged on the centre pillar;[3] this would only change in 1960, when the 1100 started to adopt the more modern bodyshell of the Fiat 1200 Granluce saloon.

At the October 1953 Paris Motor Show, Fiat launched a sporting version of the 103, the 1100 TV—standing for Turismo Veloce, "Fast Touring".

[7] Another notable mechanical difference was the propeller shaft, two-piece instead of one-piece in order to dampen torsional vibrations, intensified by the increased engine output.

[7] A distinguishing trait of the TV was a single front fog lamp, inset in the grille and flanked by two chrome whiskers.

Specific exterior trim included thicker chrome spears on the sides with "1100 TV" and "Fiat Carrozzerie Speciali" badging, a taller bonnet ornament, special hubcaps, and whitewall tyres.

Inside it featured a tortoiseshell celluloid two-spoke steering wheel, two-tone cloth and vinyl upholstery, colour-coded fully carpeted floor, and until the end of 1954 reclining buckets which could optionally be fitted instead of the standard bench seat.

[7] A new 1100 body style was introduced at the 1954 Geneva Motor Show, a five-door estate named 1100 Familiare on its home market.

[10] A third row of two forward-facing jump seats allowed to carry a fifth and sixth passenger, folding level with the boot floor when not in use.

From 1954 to 1956 Italian coachbuilder Pinin Farina independently built and sold a 2-door 2+2 coupé based on 1100 TV mechanicals, in a small series of about 780 examples.

[14] The design was first seen on a one-off displayed at the 1953 Paris Motor Show and entered by Umberto Agnelli at a race event held in 1954 near Turin, the Orbassano 6 hours Cup.

[14] The hand-built body was steel with aluminium doors, bonnet and boot lid; starting from 1955 a panoramic rear window was used, similar to the one found on coeval Pinin Farina-bodied Ferraris.

Luggage space was improved by adopting a fold-down rear backrest and moving the spare tyre under the boot floor.

In September 1957 the 1100 was updated again as a 1958 model, most notably with a completely redesigned rear end, and took on the new type code 103 D. It premiered at the Paris Motor Show in October, together with the new 1200 Granluce.

Therefore, the 1100 range was left temporarily without an upmarket variant, and consisted of just two models: saloon and estate, both sporting contrasting colour roofs as standard.

[5] Exterior distinguishing features of the 1958 model were a new grille made of thin vertical bars crossed by four horizontal ones, with a Millecento (1100 spelled out in Italian) script on its centre, and "stepped" chrome spears on the sides.

[16] In 1959 Fiat re-introduced an upmarket 1100 model, positioned between the standard saloon and the 1200 Granluce: the 1100 Lusso (type 103 H), also known as De luxe or Luxus on foreign markets.

At the front for the first time on a 1100 the Fiat badge was moved from the bonnet to the centre of the grille, featuring a new square mesh radiator.

The body-side chrome spear split in two to encompass a contrasting colour band (matching the roof paint) extended from the front doors to the end of the rear quarter panels, where there was a brass-plated ornament.

New interior features were a padded vinyl shelf added below the dashboard, and wind deflectors fixed to the front side windows.

Late in 1960 the 1958 1100/103 D and the 1110/103 H Lusso were replaced by three models, first shown at the November 1960 Turin Motor Show: the 1100 Export, the pricier 1100 Special, and the 1100 Familiare station wagon.

Both had been stripped of the Granluce and Lusso's glitzy trim and their complex paint schemes—though a contrast colour roof remained optional on the Special.

The 1100 D was a successful Italian family car in the early sixties and was accompanied by a Familiare (estate version) and a Deluxe model that offered a higher performance of 50 PS (37 kW), extra side moldings, front bench seat with two reclining backs and carpet floor mats.

In terms of styling cues, the vestigial fins were further suppressed and the simple round rear light cluster from the Fiat 850 replaced the vertical form seen on the 1100 D.[23] At the same time, the larger engine was withdrawn in order to avoid undue overlap with the 124.

The boot was usefully expanded, helped by a slight increase in the car's overall length, and with more careful packaging of the spare wheel (under the floor) and the fuel tank (in the rear wing on the right).