Alfa Romeo 155 Q4: The Homologation Special With the Delta Integrale's DNA
In the early 1990s, Alfa Romeo needed a road-going, four-wheel-drive 155 to homologate for Group A touring car racing — the 155 Q4 was the answer, and it's a more interesting car than its reputation as "just" a homologation special suggests.
The technical story
Under the hood is a 2.0-liter turbocharged Twin Spark four making 190 hp, paired with a genuinely sophisticated permanent four-wheel-drive system: a front differential, an epicyclic center differential with a Ferguson viscous coupling, and a Torsen self-locking unit at the rear. That driveline architecture is closely related to the system in the Lancia Delta Integrale — both cars were engineered under the same corporate umbrella at the time, and it shows in how they drive: similar turbo character, similar all-weather composure, wrapped in a much heavier three-box sedan body.
Three different 155 racing stories — and only one of them is this car
Here's where the record needs setting straight, because the 155 nameplate actually raced under three completely different rulebooks, and it's easy to conflate them. The Q4 itself was the homologation base for Alfa's Group A and Italian Superturismo efforts in the early '90s — a real four-wheel-drive, turbocharged race car built to a real production-based rulebook. Alfa's headline-grabbing DTM dominance in the mid-1990s, with Nicola Larini and the factory Alfa Corse team, actually came from a completely different car: the 155 V6 TI, a purpose-built silhouette racer with a naturally aspirated 2.5-liter V6 making well over 400 hp, sharing no meaningful architecture with the road-going Q4. And in Britain, Alfa's factory-backed 155 that won the 1994 British Touring Car Championship with Gabriele Tarquini ran under yet another rulebook — the 2.0-liter naturally aspirated, front-wheel-drive Super Touring regulations that banned both turbos and four-wheel drive outright. Three famous 155 race cars, three different sets of hardware, and only the Q4 in your driveway shares real DNA with the one built to make road-car homologation legal in the first place.
Only 2,701 Q4s were ever built (2,591 in the initial run plus 110 more between 1995 and 1997), which makes it one of the rarer Alfas of the era — and arguably the most honest of the three race-connected 155s, since it's the only one you can actually buy and drive on the street today.
How it compares to its rivals
Period cross-shops for a fast, all-weather sports sedan included the BMW E30/E36 M3, the Mercedes-Benz 190E 2.5-16 Cosworth, and the Audi 80 quattro — all rear- or all-wheel-drive sport sedans chasing the same touring-car-bred credibility. The Q4's permanent 4WD system set it apart from the BMW and Mercedes in particular, trading some of their sharper rear-drive balance for genuinely usable all-weather grip.
What the market looks like right now
So few 155 Q4s were built, and so few come up for sale in any given year — especially outside Europe — that there isn't a deep, reliable US pricing history to point to the way there is for the Delta Integrale. What that means in practice: expect a real premium over a comparable non-Q4 155, expect negotiations to move slowly given how few directly comparable sales exist, and expect a dealer with two in stock at once, like EuroClassix currently has, to be a genuinely unusual opportunity rather than the norm.
What to know before buying one
Rarity cuts both ways for ownership — parts sourcing for the driveline components (the viscous coupling, the Torsen unit) will likely mean working with Italy- or Europe-based Alfa specialists. Verify matching numbers given how few remain, and check the condition of the 4WD hardware specifically, since it's both the car's most distinctive feature and its most expensive system to put right if neglected.
Frequently asked questions
Is the 155 Q4 the same car that won DTM? No — that was the separate, purpose-built 155 V6 TI silhouette racer, a common point of confusion this article exists partly to correct.
What does "Q4" mean? It denotes Alfa's permanent four-wheel-drive system on the 155, engineered with real architectural overlap with the Lancia Delta Integrale's own 4WD hardware.
How rare is it really? Only 2,701 were built across the full production run (1992–1997) — genuinely one of the rarer Alfas of its generation.
Currently available at EuroClassix
Two 1992 examples are in the collection (ECC-329 and ECC-331). See both on the For Sale page.