Classic CarsOct 15, 2026

Alfa Romeo 8C 2900

The supercharged straight-eight that swept the Mille Miglia, often called the "Immortal 2.9."

The 8C ("eight cylinders") family began with Vittorio Jano's straight-eight, Alfa Romeo's main racing engine from 1931 to 1939. The ultimate road-going version was the 8C 2900, with its bore and stroke enlarged to 2,905 cc. The 8C 2900A was shown at the 1935 London Motor Show, and only ten were built. The more road-friendly 8C 2900B followed in 1937, offered in Corto (short) and Lungo (long) wheelbases. Most were bodied by Carrozzeria Touring and a few by Pinin Farina. Thirty-two 2900Bs were built in regular production, plus one more assembled from parts in 1941.

Racing pedigree

The 2.9 dominated Italy's legendary road race. Scuderia Ferrari, then Alfa's racing arm under Enzo Ferrari, entered three 8C 2900As in the 1936 Mille Miglia and took the top three places, with Marquis Antonio Brivio winning. In 1937 Carlo Pintacuda won, with Giuseppe Farina second. For 1938, Alfa Corse prepared four 8C 2900B Corto roadsters with Touring Superleggera bodies. Clemente Biondetti won in a car fitted with a Tipo 308 Grand Prix engine of about 295 bhp, with Pintacuda second. The 2900A also won the 1936 Spa 24 Hours, and a Mille Miglia roadster won Spa again in 1938.

Key specs

Engine: 2,905 cc DOHC alloy straight-eight with twin Roots-type superchargers
8C 2900A: 220 bhp at 5,300 rpm (detuned from the Grand Prix engine)
8C 2900B: 180 bhp at 5,200 rpm; Corto wheelbase 2,799 mm, Lungo 3,000 mm
Brakes and suspension: hydraulic finned-alloy drums, independent front wishbones, rear swing axles

Collector values and news

The 2.9 is one of the most valuable prewar cars in the world. In August 2016, RM Sotheby's Monterey sold a 1939 8C 2900B Lungo Spider by Touring for $19.8 million, then the highest price ever paid at auction for a prewar car and still the Alfa Romeo auction record. In 2019, Artcurial in Paris sold a 1939 Touring Berlinetta for $18,977,200. More recently, Gooding sold a 1938 Lungo Spider at Pebble Beach in August 2024 for $14,030,000, below its $16–20 million estimate.

Sources: Wikipedia: Alfa Romeo 8C; RM Sotheby's: 1939 8C 2900B Lungo Spider, Monterey 2016; Classic Car Auctions: most expensive prewar car; ClassicCars.com Journal: $18.977M at Artcurial; Gooding: 1938 8C 2900B Lungo Spider

Mechanics

Chassis

8C 2900B wheelbases: Corto 2,799 mm, Lungo 3,000 mm (2900A: 2,718 mm)
Mostly bodied by Carrozzeria Touring (Superleggera on the 1938 Mille Miglia roadsters), a few by Pinin Farina
19-inch wheels

Offering two wheelbases let Alfa serve both racing-style spiders and long, elegant tourers from one chassis. Touring's Superleggera bodies kept weight down for the Mille Miglia cars.

AI-rendered 3D illustration, 80s neo-pop style: Alfa Romeo 8C 2900 chassis, labelled — Illustration: Idle & Rev (AI-rendered, for illustration; not to scale)

Suspension

Front: independent wishbones with coil springs
Rear: swing axles with radius arms and a transverse leaf spring
Brakes: hydraulic, finned-alloy drums (17-inch)

Four-wheel independent suspension was advanced for the 1930s and was a big part of why the 2.9 could be driven so fast on rough Italian roads. Cars of the period were usually built on rigid axles.

AI-rendered 3D illustration, 80s neo-pop style: Alfa Romeo 8C 2900 suspension, labelled — Illustration: Idle & Rev (AI-rendered, for illustration; not to scale)

Engine / Powertrain

0–60 mph: about 9.4 s for a Touring-bodied 8C 2900B in a short Autocar trial, as reported by secondary sources (the original test wasn't available to check)
Vittorio Jano straight-eight, 2,905 cc (68 × 100 mm), DOHC alloy construction, twin Roots-type superchargers
8C 2900A: 220 bhp at 5,300 rpm; 8C 2900B: 180 bhp at 5,200 rpm
1938 Mille Miglia roadsters: 225 bhp; Biondetti's winning car used a Tipo 308 GP engine of 295 bhp
4-speed manual transaxle

This was a Grand Prix engine lightly detuned for the road. That is what made the 2.9 the supercar of its age, and it carries a central gear tower and twin superchargers.

AI-rendered 3D illustration, 80s neo-pop style: Alfa Romeo 8C 2900 engine, labelled — Illustration: Idle & Rev (AI-rendered, for illustration; not to scale)

Mechanics sources: Supercars.net: 8C 2900B (cites Autocar); sportscars.tv: 2900 Alfa Romeo (cites Autocar); Wikipedia: Alfa Romeo 8C; Gooding: 1938 8C 2900B Lungo Spider specs

On track

Alfa Romeo 8C 2900 at speed · AI-rendered illustration by Idle & Rev, not real footage

Gallery

**1938 8C 2900 B Corto Spider by Touring, Pebble Beach Tour d'Elegance 2010**
Photo: Jay Cross via Wikimedia Commons · License: CC BY 2.0

**1937 8C 2900 B by Pinin Farina, Pebble Beach Tour d'Elegance 2021**
Photo: Guy Churchward via Wikimedia Commons · License: CC BY 2.0

**8C 2900 Le Mans (s/n 412033) racing at the Coppa Gallenga, 1949**
Photo: Unknown photographer via Wikimedia Commons · License: Public domain

**Interior: 1938 Alfa Romeo 8C 2900B Spider Touring cockpit**
Photo: Rex Gray via Wikimedia Commons · License: CC BY 2.0