Many of the great race engines have their origins in a road car.
Some were developed with a specific race series in mind while others went on to power many and varied competition cars. Here’s our list of the best engines that went from road to race, in alphabetical order.
Audi’s development of four-wheel drive from a military truck to rally stage is well documented, but the Quattro’s 2.1-litre five-cylinder motor had more prosaic beginnings. It started life in Audi’s saloon models with a turbocharged 170bhp. For the all-wheel drive coupe, it gained a further 30bhp to take it to 200bhp, giving 0-60mph in 7.1 seconds and 137mph in 10-valve form.
To qualify for the World Rally Championship, the five-cylinder engine had to be reduced in capacity from its normal 2144cc to 2133cc. This was to keep the engine under the 3.0-litre limit, arrived at by multiplying the turbo engine’s capacity by 1.4. In this form, the engine gained four valves per cylinder, a KKK K27 turbocharger and delivered 300bhp at 6700rpm. Subsequent A1 and A2 versions produced 350bhp, while the Sport had 444bhp in rally trim. The final fling for this engine came with the 473bhp S1 E2 Quattro that arrived just ahead of the Group B rally class being banned after a series of fatal crashes. It developed and official 473bhp, but the true figure was north of 500bhp with help from an air recirculation system to reduce turbo lag. Audi also used a 690bhp derivative of this engine in the RS 002 concept car, but it was never driven in anger.
When BMW launched its 1500 Neue Klasse saloon, survival rather than motorsport was on its mind. The company needed this car to succeed and it did, which then led on to more powerful sporting models such as the 2002 Turbo. BMWs also enjoyed plenty of wins in motorsport with the M10 four-cylinder engine in the 1800ti, 2002 and the first 3 Series, as well as in Formula 2 with more than 300bhp. However, 1983 was the real turning point. Brabham needed a new engine and BMW created just the thing with a turbocharged 1.5-litre derivative of the M10, named M12.
The simple four-cylinder engine was strong, reliable and produced as much as 850bhp in qualifying trim, with 640bhp for races. It was also much more compact than rivals’ V6 and V8 motors, so the Brabham was more aerodynamic. As the engine developed through the mid-1980s, it was claimed to produce as much as 1400bhp in qualifying trim, though reliability was marginal it did make the BMW motor the most powerful Formula 1 engine to date. A ban on turbocharging from 1989 put an end to the M12’s racing career.
Chevrolet’s small block V8 was in production for almost 50 years and powered everything from pick-ups to luxury limos. Almost as soon as it was launched in 1953, hot rodders and drag racers realised its potential and made full use of it. It quickly became the go-to engine for stock car racing, while Chevrolet adapted it for the Trans Am series with the Z/28 Camaro. Little wonder this V8 is the most successful engine in NASCAR and USAC oval racing.
However, the Chevy V8’s development spread much further than just the US. British firm Lola used it in its T70 sports racer, winning five out of six races in the 1966 Can-Am series, and raced it at Le Mans. Corvettes have also used this engine in many races and won their class at Le Mans.
The Colombo-designed Ferrari V12 engine had an unusual race-road-race-road development history. It started off as a 1.5-litre engine for the 125 S, which was a pure racer, but was then enlarged and civilised for the 166 and 212 road cars. With the arrival of the 250 line in 1952, Ferrari created many of its definitive models. Some were glamorous coupes and roadsters, built to help fund racing activity, while the 250 GT SWB gave the Italian firm a formidable rival to Aston Martin, Jaguar and Maserati.
By this stage, the V12 had grown to 3.0-litres and produced 280bhp in the GT SWB, but more was to come in the 250 GTO that had 300bhp. The GTO proved dominant between 1962 and 1964, yet the V12 motor lived on in various Ferrari road cars, as well as powering the racing versions of the Daytona with as much as 450bhp from a 4.4-litre unit. The final fling for this mighty engine was in the 412i with 5.0-litre capacity to power this near-two tonne four-seat tourer.
Cars don’t get much more humble than the Fiat 850, introduced in 1955. However, as soon as Carlo Abarth got his talented hands on the Fiat, he turned it into the Abarth 850. The stock 747cc four-cylinder engine was enlarged to 847cc by increasing the bore and stroke, as well as having its compressing raised to give 52bhp at 5800rpm compared to the standard motor’s 29bhp.
Other changes for the engine included a Solex 32 carburettor and spikier camshaft, which helped the 850 to a top speed of 81mph. If that wasn’t sufficient, a 1000 model with up to 112bhp could hit 125mph. In the 1961 Nürburgring 500KM race, Abarth 1000s finished first and second outright, while 850s and 1000s enjoyed considerable success in the European Touring Car Championship.
The Ford Anglia’s ‘Kent’ engine is, arguably, the most successful engine ever in motorsport. It’s powered thousands of cars to victory around the world in many forms of racing and it all started with the lowly Anglia launched in 1959. This ‘pre-crossflow’ version, with intake and exhaust on the same side, showed a willingness for being tuned and was quickly adopted for use in cars such as the Lotus 7. Lotus also used the engine as a base for its double overhead camshaft derivative that powered the Elan, Lotus Cortina and Escort Twin Cam that all enjoyed race success.
Yet more was to come as the Kent engine became the standard unit in the hugely popular Formula Ford cars that continue to be raced around the world. The engine was also used in Formula 2 and 3, while today motorsport tuners are extracting as much as 220bhp from the later Crossflow variants for historic racing series.
After the success of the SierraCosworth in Touring Car racing, it was inevitable Ford couldn’t let rivals steal the show in the mid-1990s. It came up with a Mondeo-based car, but the Duractec 2.5-litre V6 found itself at odds with the rules for a 2.0-litre class. The obvious thing would have been to use the Mondeo’s four-cylinder 2.0-litre petrol engine as a base, but Ford instead asked Prodrive to create a 2.0-litre version of the V6 motor, mounted as low down and far back as possible in the chassis.
Prodrive met the brief perfectly and the slimmed down V6 produced as much as 305bhp. Success took a little longer to come, but the Ford Mondeo eventually scooped the Drivers’ and Manufacturers’ titles in the 2000 British Touring Car Championship.
Mazda’s Le Mans win in 1991 was the highlight of its rotary engine in motorsport, but development started all the way back in 1968 when the company entered a pair of Cosmo coupes in the 84-hour Marathon de la Route at the Nürburgring. One crashed, the other finished and spurred Mazda on to develop the technology. In 1970, Mazda’s 10A rotary engine powered a Chevron at Le Mans, while Sigma cars used a 12A motor in 1973 and ’74.
This led to a Le Mans entry in 1979 with an RX-7, while the 1981 RX-7 had a 300bhp 13B twin-rotor engine to compete in the up to 2.5-litre class in the 24-hour race. 1983 saw Mazda shift to the Group C formula and its 717C car used the same 13B engine. The 757 car of 1987 introduced the three-rotor 13G Wankel engine that worked better as a link to the four-rotor engine than it did on the track. This 600bhp 13J rotary gave way to the R26B that had four 654cc chambers, giving a 2.6-litre capacity and 700bhp. This gave Mazda its much wanted Le Mans victory and it was a car of many first, including first and only rotary-powered car to win the race, first Japanese manufacturer to win Le Mans, and the first car to win the race with carbon brakes and clutch.
The A-Series engine used in the Mini had been around since 1951 and already had some competition success in the likes of the Austin A35 and Austin-Healey Sprite. However, it was the compact, agile Mini that proved the catalyst for the A-Series huge motorsport successes. It started with the launch of the tuned Cooper version in 1961 with the basic 848cc motor increased to 997- and then 998cc with 55bhp on tap instead of a mere 34bhp.
The Mini got into its stride with the 70bhp 1071 Cooper S, which performed well on track and stage, but BMC (British Motor Corporation) had to introduce the homologation 970S in 1964 to meet racing regulations. This was achieved with a short-stroke version of the 1071 engine, resulting in a 970cc capacity, 65bhp in road trim, and up to 10,000rpm for race-prepped motors. The ultimate evolution of the A-Series from BMC’s competition department was the 1275S, which was capable of 115bhp at 7000rpm for rallying compared to the road car’s 76bhp. This was enough to help the Mini win the Monte Carlo Rally three times between 1964 and 1967, and it would have been four in a row had it not been for a trumped-up infringement. It didn’t stop the A-Series going on to being a dominant force in Formula Junior single-seater racing, as well as entering the British Touring Car Championship in 1978 and winning its class and the outright title in 1979.
When Nissan revived the Skyline name with the R32 in 1989, it already knew it was going racing with the car in the All Japan Touring Car Championship the following year. It meant reworking the twin-turbo 2568cc RB26DETT engine from its stock 276bhp to something more race-worthy. What Nissan ended up with was 543bhp, which increased to 650bhp in later years.
Although the engine’s capacity remained the same as the road car’s, little else did. Pistons, con-rods, crankshaft, cams, fuelling, oil system, cooling, and electrics were all uprated to deliver maximum performance. This approach worked to perfection and the Skyline won all 29 races it entered in the Japanese series, plus many more in others, and earned the factory-entered car the nickname ‘Godzilla’.
Motorsport and Porsche go hand in glove with each other, and nowhere is that relationship more rooted than in the 911. It didn’t take long after the car’s launch for Porsche to enter rallying with the early 1991cc model, which enjoyed plenty of success as capacity grew to 2195cc and power was increased. Focus switched to track racing with the Carrera 2.7 RS, which was built to meet the 3.0-litre category rules. Although the engine was based on the fuel-injected 2.4-litre road car’s, it had a magnesium crankcase and aluminium cylinders with a Nikasil coating to reduce friction and retain enough strength in the engine that might otherwise be lost through boring it out for a larger capacity.
The bore was increased to 90mm to give a capacity of 2687cc and power of 210bhp, up from the 2.4’s 190bhp. It also had 11 cooling fins on the cylinder barrels compared to the 15 of the 2.4-litre engine. This uprated engine then allowed Porsche to run the 2.8 RSR in Group 4 racing, with the bigger engine producing 300bhp thanks to more aggressive camshaft profiles, higher compression, and larger valves. This was followed by the 3.0 RS road car and RSR racing model, and then the RSR Turbo in 1974. Out of this came the 935 Group 5 race car with its twin-turbo 3.3-litre flat-six engine with as much as 845bhp, enough to see it take 70 victories in the IMSA championship in the USA.
As unlikely starting points go, few are more unexpected than the Reliant’s small engines. However, there’s plenty of logic in choosing this motor as a replacement for the ageing Austin 7 for the 750 Motor Club’s core series. The 1972-75 engine came with a 748cc capacity, so was a neat successor to the Austin, and it had an aluminium block and head to make it light. It also revved freely and responded well to tuning, along with modifications to the oil system and water pump for racing.
An 848cc version of this engine arrived in 1975, giving 40bhp as standard compared to the 748’s 32bhp, though race engines can produce as much as 80bhp. To reach this, the cylinder head needs to be ported to improve flow and stronger valve rockers fitted, new camshaft fitted, and most drivers change the original Lucas distributor for electronic ignition for reliability. As supply of the Reliant engine dwindled when production ended in 2003, the 750MC moved to a Fiat engine as the basis of its racing activity.
The run of the mill Renault 8 got a shot in the arm with the arrival of the Gordini version shortly after its launch in 1964. With 95bhp versus the standard 45bhp, the Gordini was a genuine 100mph rival for the Mini Cooper S. However, Gordini was far from done with the car and took its roadgoing model and created a racing version to meet Group 2 motorsport regulations.
The biggest change was an increase in engine capacity to 1255cc, achieved by increasing the bore from 65mm to 74.5mm. Compression was also raised to 10.5:1 which, along with an aggressive cam profile and twin Weber or Solex carburettors, upped power to 110bhp at 6750rpm. All of this made the Gordini an effective rally car, winning the 1965 Tour de Corse ahead of an Alpine that used a more powerful 1300cc version of the Gordini motor.
Rover and then British Leyland were both slow to realise the competition potential of the Buick-designed V8 engine. This was despite the same motor being used by Mickey Thompson in his 1962 Indianapolis 500 car driven by Dan Gurney. Others were also quicker to spot the V8’s sporting prowess, such as Morgan with its Plus 8 that was success on track.
The Triumph TR7 V8 was the first works car to adapt the Rover V8 for competition, not the TR8 which wasn’t on sale until 1979. In this form, the TR7 raced in the TransAm and IMSA series in the USA, while in the UK the car was used for rallying. The 3.5-litre engine gained four downdraught Weber carburettors and dry sump lubrication, contributing to its 260bhp initial output that eventually increased to 300bhp. Rover also used the engine for its SD1 touring car, built with help from Tom Walkinshaw’s TWR outfit, that delivered many wins. The SD1 V8 was also used for rallying in 1984 and 1985.
Saab had already enjoyed plenty of rallying success, and even an outing at Le Mans in 1959, by the time it launched its 96 model in 1960. It retained a two-stroke engine, a three-cylinder 841cc motor in this case. To improve power for rally use, Saab fitted triple carburettors, a gas-flowed cylinder head, raised the compression ratio, and added oil injection to overcome lubrication issues with the two-stoke design. It resulted in around 70bhp for the works rally cars.
If the tiny two-stroke Saab was unusual, it was also effective as Erik Carlsson won the RAC Rally in 1960, ’61 and ’62, as well as the Monte Carlo Rally in 1961 and ’62. Such success resulted in a roadgoing models called Sport and Monte Carlo that had a 57bhp version of the triple carb motor.
Subaru had been involved in rallying for many years by the time it introduced the Impreza in 1992. It replaced the compact Leone and borrowed the 2.0-litre turbocharged engine from the Legacy, which had been upholding the firm’s rallying honour. The Impreza Turbo road car had a 218bhp 1994cc flat-four engine, and Subaru had designed this car with rallying in mind. It meant the capacity remained unchanged, but the engine gained bigger valves, reworked ignition timing, and bigger turbo, though a 34mm air restrictor was mandated by the FIA from 1995.
The result of Subaru and Prodrive’s work was an engine that produced between 300- and 360bhp at 6500rpm depending on the state of tune. What mattered more for rallying, however, was the torque of 324lb ft at 4000rpm, which later increased significantly to more than double the road car’s 201lb ft. All of this made the Impreza the rally car to have in the mid-1990s.
Volkswagen was happy to leave competition to its associate Porsche, which used the Beetle as the original base of its 356 model. However, Paul ErnsteStrahle and co-driver ViktorSpingler reckoned the Beetle was the ideal car to use for the 1954 Mille Miglia road race. Strahle had already competed in various rallies in a Beetle, but for the Italian event he decided to tune up his car using Porsche parts, resulting in a 65bhp 1300cc engine. When the Italian organisers realised the German amateurs could upstage the local Fiats, the put them in an unfavourable starting position, but it didn’t deter Strahle and Spingler from finishing and winning their category.
Later on, others used the Beetle flat-four engine in everything from drag racing to the single-seater Formula Vee cars. Perhaps the Beetle engine’s best competition outings have been in desert racing, where they have powered many purpose-built machines to victory with power outputs as high as 200bhp.
Volvo may well be unique in reducing the capacity of an engine and removing its turbocharger to gain more power for racing. This was required for the 850’s 2319cc five-cylinder turbo to get down to 1999cc to meet the Super Touring rules for the British Touring Car Championship in 1994. The work was hand to UK firm TWR, which used some cunning engineering to improve the exhaust valve angle and increase power to a claimed 325bhp form the standard motor’s 240bhp.
Mounted much lower and further back in the 850’s chassis, the 2.0-litre engine revved to 8500rpm and drove through a six-speed sequential gearbox. It wasn’t the quickest car in the 1994 BTTC, but it more than did the job of changing Volvo’s image and bringing in new customers.