Wednesday, December 31, 2014

Volumetrico 131

Here is a brief description of this car from Sporting Fiats Club site:
"During the Summer of 1980 FIAT presented two 131 prototypes to the European motoring press. These were based around 'blown' versions of the earlier 131 Racing/ Sport having supercharged 1300cc and 2000cc engines producing 115 and 142 bhp DIN respectively.

The Abarth designed, positive displacement blower was belt driven and operated via a special Weber carburetor. This is a similar design to the supercharged versions of the 124 Spidereuropa and Lancia Beta Volumex but with a larger volume blower.

In August 1981 these “Volumetrico’ 131’s were launched with 7.6:1 compression engines, oil cooler, electric fuel pump, special exhaust and a completely upgraded suspension and brake package. Their Pirelli ‘Plus One’ wheels and oval exhaust tail pipe were similar to the early 130tc Strada Abarth. All cars were assembled and prepared at Abarth.

Other than the slightly lower ride height and rear ‘Volumetrico’ badges, there was little external difference to the standard SuperMirafiori series three. Except this one would take a lot more catching! Top speed was quoted at 101mph because of the 10/39 diff. ratio but, as with all the supercharged twin cams, the torque output was fantastic (21.8 mkg DIN at 3600rpm in comparison to the Rally 131 Abarth’s 18 mkg DIN!). 0 to 60 time is under 7 seconds.

Fuel efficiency of the 2 litre was 24 to 27 miles per gallon. This bares comparison to any tuned twin cam prior to the modern Weber/ Marelli engine management systems. Impressive!"

Family Saloon

Family Saloon to Sporting Flyer
Introducing the 131
There's something odd about the way the 131 range was launched - especially when you consider what it became. The 131 Mirafiori range was announced in September ‘74 as a direct replacement for Fiat's medium size 124 saloon. But the 131 began life as a technical step backwards.... the 124 series it replaced had the famous 'Sports' and 'Specials' with advanced ride and sophisticated twin cam power units. In fact the Fiat 124 was the first mass production car to have a twin cam engine in Europe.
But then the 131 is launched with small pushrod engines and a side mounted camshaft. Yes the 131 was simple and practical but hardly what the motoring press had expected. You see the motoring world was trying to recover from first big oil price hike, and being the first, it had come as a nasty shock. Part of Fiat had been looking for frugal, frightened buyers ever mindful of their wallets, and assumed they would want to keep the cost of motoring cheap above all else.
Fortunately for us there was another side to Fiat in the seventies - determined to exploit a new and fast growing market for in-the-street performance. This was expressed in the rally cars and the popularity of the newly forming world rally series. Several manufactures had seized on the vast marketing opportunity of driving their products at high speed passed hundreds of thousands of potential buyers. Fiat had the will and experience to deliver truly competitive cars.
It only remained for the final choice of car to be made to carry the Fiat world rally banner. In the end the X1/9 Prototipo (and potential Stratos beater) was rejected in favour of the mundane 131. The resulting rally weapon really was awesome. And so the second part of the 131's life became everything those motoring journalists might have predicted from looking at the 124.
See also the 131 Abarth Model Page

The history of the 131 is something of a Jekyll and Hyde tale. Go back to 1972 and in May Fiat launch the 132 - their new large saloon. There are three versions of the 132 produced, with different capacities of a new Twin Cam engine first seen in the 124 series. These are the 1600cc, 1800cc and 1800 Special.
Within months, the world is in the grip of a Middle East war-induced oil crisis. One of Fiat’s early responses can be seen in the first 131s (yes, the 131 was so named after the 132 was launched!).

Early 131 models had a four speed box, rack and pinion steering, rear axle and drive with a 5 link trailing arms/ Panhard rod set up, front suspension was Mcpherson strut with a lower wishbone and anti roll bar. The advanced engine and suspension designs of recent models were lacking. Few of the 132 mechanical innovations were present.
Reception to the 131 could be politely summed up as look warm. The car was ‘easy’ to drive, with no vices, a quiet comfortable ride, good maintenance access and just about adequate power for the job.
So how was this car propelled into classic stardom and World Rally Championship success?

131 Milestones
1974 October
131 introduced with 1300 or 1600cc pushrod engines
in 11 model range, 2 or 4 door, plus 1300 estate. Specials had enhanced trim & twin lights
Rack & pinion steering, limited slip diff option on 1600S.
Abarth continue developing 131 prototypes including the 031 and 035 based on 131 shells
1976 March
131 homologated for Group 4 World Rallying
1977131 Abarth wins first World Rally Championship 
1978 March
Super mirafiori introduced with 1300cc and 1600cc Twin Cam engines, 5 speed box,
Estates called Panorama
Wider wheels on all models.All models have trim enhanced
1978 May
Diesel estate introduced with 2000cc or 2500cc engines
1978 September
131 Racing (Sport in UK) introduced with twin Webers and 2.0l Twin Cam engine. Trim levels altered, twin headlights, spoiler, remote gear change
Alloy wheels optional
Sport had larger clutch
131 introduced in the States as the Brava with emission controls and 2.0l engine.
Later injection added.
1980131 Abarth wins final third World Rally Championship(1977, 1978, 1980)
1981 March
3rd series of 131 in two configurations Mirafiori & Super mirafiori. 1300cc now 1400cc single overhead cam. Superior gets 2.0l Twin Cam power
131 Sport & 2 doors discontinued. Trim levels enhanced
1981131 sales pass 1.5 million 
Limited edition Abarth Volumetrico. Fastest of the road 131s. Supermirafiori with Abarth mods.
Volumex supercharged
131 production ceases
Fiat did not promote the normal 131 as a performance car. It was not until March 1978 with the Super Mirafiori that the 131 was fitted with a twin cam engine – in 1297cc and 1585cc versions, both with 5 speed manual boxes, improved seats and interior trim, and wider wheels.
In 1977 the 131 had won its first world rally crown - and yet it was September 1978 before a more serious attempt to emulate the rally cars arrived - with the 2 litre Mirafiori ‘Racing’. In the UK it was called the 131 Mirafiori ‘Sport’ in deference to concerns about the use of the term racing on a road car. The Sport was only available as a two door, with twin choke carbs, electronic ignition, remote Abarth gear Frank Church's 131 Sport at Brooklands 1999shift, 5 speed box, 115bhp @ 5800, 123 lb/ft max at 3600rpm.
It also had 5.5j wheels and alloys as an option. 0-60 10.2secs, and 112mph top speed.
The 131 Sport restored some of Fiat’s reputation for high value performance. Press and public reaction to the Super Mirafiori and Mirafiori Sport was very positive. They had much livelier performance and greatly improved grip.
From 1979, they were also marketed to the States, as the Brava, in both 2 door, 4 door and Station Wagon forms with auto box and air con. options (imports ceased in 1981). These cars either had emission constricted 80bhp or a fuel injected 102bhp engines (the latter similar to the 124 Spider 2000).
In March 1981 the 131 range was upgraded and launched at the Geneva Motor Show. The original 1300 and 1600 models now had revised 1367cc and 1585cc sohc engines. Though the Mirafiori Racing/Sport was discontinued, the 2 litre SuperMirafiori TC (twin cam) was effectively a four door Mirafiori Sport. All had new grills, bumpers, rear lights, and revised instrumentation. This final version of the Super Mirafiori was offered with 1367cc, 1585cc, or 1995cc Twin Cam engine options. After 10 years production, the 131 run was ended in 1984 when the Panorama estate car was discontinued.

The 131 Abarth Model Page looks at Abarth's development of the 131 from test bed into world beater and details the range of 131 prototypes all usually bracketed under the 131 Abarth 035 too.

131 Racing/ Sport

Introduced in September 1978, the bodies were prepared for sports use with additional spot welds, bracing and a two-door body. The 1995cc engine derives its design and engine bay layout from the 132 series cars of similar capacity. However, in the 131 Racing, the engine is located further back.
The Racing has a new front end with revised grill and twin halogen headlights that are all installed as a single unit. The bumper and front valence has an integral spoiler, and plastic trim extends around all the wheel arches.
Mechanical changes include a larger clutch, in keeping with the 115bhp engine and the new lower profile Pirelli P6 radial tyres on 14-inch wheels. Weight was 1070kg unladen, with a quoted top speed of 113mph. Fiat claimed the Racing/ Sport could return 35mpg.

131 SuperMirafiori TC 1300 - 1600 - 2000
The third series of 131s announced in 1981 were four door models. The 2 litre replaced the 131 Racing/Sport. Top of the range offered was the three capacities of Twin Cam listed below. Series three cars can be identified externally by their large plastic strips extending to the bottom of the doors, and the matching plastic bumpers that continue the line around the front and rear of the car. Inside were new seats and cloths, a new centre console and central door locking.

131 SuperMirafiori TC Spec (3 capacities) 1981
Engine 131 C1.000, 131 C3.000, 131 C4.000 Twin Cam belt driven
4 cylinder in line, 1367, 1585, 1995cc
8.9:1, 9:1, 9:1 compression
78 x 71.5 - 84 x 71.5 - 84 x 90 bore x stroke (mm)
Output 75 - 97 - 113bhp DIN @ 5800 - 6000 - 5600rpm
11.2 - 13 - 17 mkg @ 3800 - 3800 - 3600
Lubrication: rotary pump, sump cap. All 3.6kg
Coolant: pump, thermostat & booster fan 8.1 - 8.0 - 8.2 litres
Carburation 1x Weber 32 ADF 52/250 - 53/250 - 34 ADF 54/250
or 1x Solex C32 TEIE/9 - Solex C32 TEIE/10
Ignition Coil & Distributor
Fuel Tank capacity 53 litres/ 11.66 gals, electronic d.c. pump
Gearbox 5 speed all synchro, clutch: single dry plate, split prop shaft
Final Drive Rear, Hypoid bevel gearing, 9/40 - 10/41 - 12/43 ratio
Suspension Front: McPherson strut type, coil springs, wishbones, telescopic shock absorbers
Rear: rigid axle, 5 torque reaction arms, coil springs & shocks
Brakes Front: disc, single piston & swing arm caliper
Rear: drum
Weight 1060 – 1060 - 1080kg unladen
Wheels/tyres 13ins 165/60 - 165/60 - 185/70 SR Pirelli
Steel pressing with chromed rim rings, alloy optional.

Buying Guide
The 131 ‘Racing’ is sold in UK as the 131 ‘Sport’ in deference to insurance company and authority ‘s wishes.

The 131 is badly affected by corrosion in the inner sills, floor pan, and inner wheel arches.
Panels - doors are large and prone to distortion especially at lower rear of window frames.
Front wings bolt on.
Most models sold as 4 door so ‘Sport’ 2 door is more difficult to source. Possible to use the 131 1300L (2 door) as a donor for the Sport.

Relatively cheap to buy and tune, the Sport was often used as a club racer.
Superb 2 litre engine is readily tunable with twin 45DCOE carbs, increased compression and performance cams. You can expect in excess of 180bhp.
Even in good condition, the top prices for a 131 Sport will not be much more than £2000. Although tuning and body upgrades to Abarth flared arches etc. can fetch £3-4000.
The cars are rare now. Don’t expect to find one immediately.

I'll take a bet that if you ever owned one of these Sports for any time - you're now looking for a replacement! One of the most involving and flaky Fiats ever.... And one of the worthy flag ships of the Fiat Twin Cam Register! Its time to dust then off (well more likely weld and get together again!)
Frank Church was elevated to club hero status when, at Brands Hatch in 1987 he won a round of the BRSCC Italian Intermarque (Now Le Mans Euro Italia) Championship. Frank never bothered with the racing slicks sported by his competitors. On this occasion, shortly after the race started, the circuit was deluged in a cloud burst. Frank had the pleasure of driving through a field of duck-like aquaplaning fellow competitors. One of Frank’s Alfa Romeo brethren that day reported, when later asked why he hadn’t pitted to change to wets that he aquaplaned off the camber of the circuit at Paddock Hill Bend doing little more than walking pace – “The pits can be a long time coming.”
Frank said he really enjoyed his drive, and we agree – especially as he was 72 years young at the time! His beautiful grey 131 Sport is a credit to his commitment to ownership, the FTCR and SFC!
What's the Fiat Twin Cam Register (FTCR)? Its us - the Sporting Fiats Club - in original Twin Cam Only Mode. Only thing is I never went to an FTCR meeting that only had Twin Cam Fiats - and that included the AGMs. So I hope we're carrying the same sort of 'baton' in the same sort of way. Actually I'd like to see a web page dedicated to the FTCR on the site - but it awaits a volunteer to run it!

Article - Fiat 131 Abarth

Fiat 131 Abarth (1976)

iat 131 was just another forgettable mid-size family car in automotive history, but in 

1976 it gave birth to a world-beating rally car, 131 Abarth. This car won World Rally 
Championship 3 times in 4 years – 1977, 1978 and 1980. Fiat's newly acquired motorsport 
division, Abarth, was responsible for engineering the car. To homologate for the series, 
it needed to build 400 units of road going version. This resulted in the street car we are 
talking now.

The 131 Sedan might not be a good starting point for a high performance car. Its boxy body 

was designed for practicality, its small-capacity pushrod engines emphasized fuel economy, 
its non-independent rear suspension and 4-speed gearbox excelled only in cheapness. But 
it was Fiat's last and only rear-wheel-drive platform (if you exclude the outdated 124 Spider), 
and you know, RWD was a must for rallying before the age of 4WD. That's a good reason 
to select 131 as the basis for Fiat's next generation rally car.

Of course, a lot of modifications would be necessary. This started from the chassis. The rigid 

rear axle was replaced by a fully independent suspension with MacPherson struts to improve 
road holding regardless of bumps and body roll. The engine was replaced by the Lampredi-
designed twin-cam unit, now displaced 1995cc and for the first time incorporated a 16-valve
 cylinder head. This raised its output to 140 horsepower at 6400 rpm. At that time, not many 
cars in the world had access to 4-valve technology. As I can remember, only Triumph 
Dolomite Sprint, Chevrolet Cosworth Vega and Lotus Esprit had that feature. The gearbox 
was upgraded to 5-speed. Of course, all-wheel disc brakes were employed.However, the 
most obvious changes to us was the bodywork – with widened wheel arches, big air dam, 
roof and boot spoilers and extra intakes on the bonnet and the sides, 131 Abarth looked 
every bit a rally machine… perhaps even a war machine ! Bertone successfully turned the 
dull-looking 131 into a pulse-raising design. To save weight, all body panels except the roof 
and doors were made of glass-fiber while the side and rear windows were plexiglass. 
Bertone was responsible for assembling the body panels to the half finished car and then 
transferred back to Abarth for final assembly.

On the road, the 131 Abarth street version was not as uncompromising as its look suggested.

 In fact, its 16V engine was tractable at low rev and linear in its delivery. The ride was 
surprisingly civilized. After all, it was a rally car. The unassisted steering was quick and 
communicative. The car felt nimble in the twisty. Unusually for a rear-drive machine of its 
time, lift off the throttle in mid-corner could trigger oversteering. That said, get used to its 
character and treat it with respect, it could be great fun to drive.

Now looking back, the 131 Abarth was no where as spectacular as the later Group B specials

 or today's performance cars. The 980kg machine returned a power-to-weight ratio at 143hp 
in about 7.8 seconds. Top speed was only 118 mph, blame to the blocky shape. Even the 
racing version with 230 hp was not particular quick today. However, with a giant-killer look 
and a glorious racing history of 3 World Championships, who dare to say it don't worth 
remembering ?

Model 131 Abarth
Year of production 1976-78
No. produced 400 units
Size (L / W / H / WB) mm 4190 / 1720 / 1360 / 2490 mm
Layout, Gearbox Front-engined, Rwd, 5M
Engine Inline-4, dohc, 4v/cyl
Capacity 1995 cc
Power 140 hp
Torque 130 lbft
Weight 980 kg
Top speed 118 mph
0-60 mph 7.8 sec

131 Stradale

131 Stradale

Fiat 131 Abarth   P-131-abarth
Published at Geneva Motor show, march 1976, four seater 2d saloon. 75% of parts are same as in other production models.
Price in Italy at 1976 9.086.000 lires (2d 131 with 1,3 engine was 2.296.000 lires)
Made only 1975-1976
  • -76   Aproximately 400 Abarths were made. Fiberglass parts were made and fit to body by Bertone. After that body went to Fiat factory at Rivalta. 350 were sold by Italian Fiat dealers, 50 were given to Abarth for competition use.
  • 51x007
  • -78   They planned to make 5000 more because of g.1 rally regulations. This never happened due the cost of cars.

  • 0 – 100 km/h 8,2s
  • top speed 191-200km/h (varies between sources)
  • 0-400m (1/4 mile) 15,3 s
  • 0-1000m 28,66-29,4 s (varies between sources)
  • weight 980kg (fully laden)
  • front track 1460mm, rear 1456mm, wheel base 2490mm
  • height 1360mm, wideness 1720mm, width 4190mm

type 131 AR
designed by Bertone
all visible to outside is made of fiberglass, except roof, doors and area between rear lights are steel.
It had rpm gauge, clock and adjustable steering wheel.

type 131 AR.000
1995cc 84mm bore, 90mm stroke, cast iron block, pistons had little dome for CR
compression ratio 10,3-1
16 valve aluminum head, valves in 45 deg
  •  34,5 mm inlet valve
  •  28,5 mm exhaust valve
  • lift 9,9 mm
  • inlet port dia. 25mm
  • exhaust port dia. 23 mm
output 140 bhp/din at 6400rpm, torque 17,5 kg/din at 3600rpm
one Weber 34 ADF carburetor (34/34)
no oil cooler, wet sump
4-1 exhaust with 49mm pipe, two silencers

OEM gearbox is dogclutch, many cars were fitted later with synchro gearboxes due to difficult use and noise. Some sources say that synchro version was same as in other models but with specially hardened gears.
Clutch 230mm
5-speed Fiat
1. 3,612
2. 2,045
3. 1,357
4. 1,000
5. 0,870
Final drive 3,9 (39/10). ZF limited slip was optional.


Front; Independent wishbones, torque reaction arms, anti rollbar,McPherson type absorber/spring
Rear;  Independent, trailing arms, antirollbar, coil springs, McPherson type absorber/spring. Fiat tested also DeDion type rear axle, but noticed it terrible!
Wheels alloy Chromodora 15×7″ , Pirelli P7 195/50 VR 15 tires
In one article reporter said that anti rollbars are adjustable in street version too. It is propably possible to move the suspension mounting on the rollbar.

turning circle 10,6 m, steering wheel turns 3,4 rounds

4 x discs, mechanical handbrake
Front caliber with one 48mm piston, disc dia. 227mm
Rear caliber with one 34mm piston, disc dia 227mm




More Photos -

Great Reference - Many Facts

131 Mirafiori… plus Abarth…equals World Rally Champions x3
Overnight pitstop at Oulton Park on the 1978 Lombard-RAC Rally
Introducing the 131 Abarth
To begin with the 131 did not look a very likely candidate as a World beater. When launched the road version didn't even have a Twin Cam engine option. And yet the 131 was to become the dominant rally car at the end of the seventies. It all started with a debate within Fiat..........
Out of the confusions of the mid seventies oil crisis, came two strands of thinking at Fiat. They still had a newly formed rally team and a recently acquired world class Abarth organisation. While in the real world potential car buyers were still reeling from the economic impacts and high petrol prices as aftershocks of the Middle East War. 
The conservative strand of Fiat thinking can be seen in the 131 Mirafiori range (announced in September ’74 as a direct replacement for the 124 saloon). The 124 Sport Twin Cam engines had gone. The 131 was a traditional saloon with a 1297cc (65bhp) or 1585cc (75bhp) push rod engine and a four speed box........On the other side stood Abarth with a competition budget and Fiat backing to further exploit the growth in motorsport - rallying in particular. Some of Fiat's marketing managers could see the impact of the Lancia Stratos, and wanted to use Abarth to provide Fiat with similar world attention. So the history of rallying Fiats, and Abarth, and Lancia with its Bertone designed Stratos war machine become very intermixed.
Its really only in the final chapters that the 131 appears. To begin with Abarth's brief was to find a replacement rally car to the 124 Abarth - and it had to be as quick as a Stratos!
Several prototypes were developed – including the Prototipo X1/9, and 128 as well as the 131. For some time, it looked as though the Prototipo X1/9 would be the next car to carry the fight to world rallying. But in the end the 131 was chosen. 
The 131 is an even more glorious choice given the capability of the Stratos to trounce most of the rally competition of the time. By 1976 the Stratos had completed its third consecutive WRC championship win. Here’s a purpose built, only just a 2 seater, wedge shaped, V6 Ferrari mid-engined monster. And its replacement is…. a 131. The contrast in looks could hardly be greater. Anyway Fiat were about to go ‘toe to toe’ with Ford for the rally crown and, in Europe at least, we were trying to forget about the oil crisis and get back to burning some more hydrocarbons in pursuit of power… we needed some serious ‘wheels’ to do it! So Fiat wanted a car that the average buyer might identify with. In this sense having a purpose built dream car in the Stratos, and a ‘street’ credible 131 together makes a lot of sense. Enter Abarth.

131 Abarth History
Many of the lessons learned by Abarth during the previous years of 124 Abarth Rally development were applied to the 131. In particular the rear suspension design is very similar, and the unreliable race inspired 16valve head from 1972 had evolved into a very reliable addition to the 1995cc engine, complete with Kugelfischer mechanical fuel injection.
Abarth had been using the 131 (and a little later the Ritmo 1500s) as development test beds for their various programmes. There are a range of 131 prototypes all usually bracketed under the 131 Abarth 035 in the books about this period… but actually a lot more prototypes were involved – including rally versions that had a few domestic rally outings. So we start with another Lancia - the Beta Montecarlo, only in 1972 it had not been decided which engine this should have. And Abarth took Fiat's V6 as the basis for testing. From late in 1973 Abarth had the first prototypes bodies of the 131 available. The 131 is a natural choice for motorsport testing - it has a big engine bay, rear wheel drive and enough room within each of its compartments to work easily, without being too wide or heavy. It was the last rear wheel drive saloon that Fiat produced in Italy.
For the next two and a half years 131s featured in Abarth's testing, in fact throughout the development of the X1/9 Prototipos. These were the first intended rally car replacement for the 124 Abarths. Only in 1975 does the 131 become the rally weapon of choice within Fiat. Bertone was tasked with assembling the 400 required to qualify (homologate) the 131 into the rally championship. 40 of these were taken in batches for Works preparation by Abarth. Later in the programme a further ten were used. The intention was to have the 131 ready for the first rally of the 1976 season.
Its final season was in 1981. Just before the arrival of the Lancia 037 Abarth in 1982.
131 Abarth Prototypes
The Abarth 030 was based on the Pininfarina X1/20 (later Lancia Beta Montecarlo/ Scorpion) and fitted with a modified version of the Fiat 130 Coupe V6 engine. It was at the moment when it looked as though Fiat might continue with their V6, and the Montecarlo might well have had one installed in the production cars. But the oil crisis of 1973 quashed that plan. In the 030, the V6 was bored out to give 3.5 litres, and was used as a development test bed by Abarth for the next two years.
The Abarth SE030 Montecarlo Prototype - artists impression
In 1974 Abarth had completed the first X1/9 prototypes using a bored out and 'stroked' engine to give an 1839cc Prototipo X1/9. Initially fitted with an 8 valve head, Abarth had plans to test a 16 valve head as soon as possible. Problems, however, in extracting reliable low rev - high torque output from the heads meant chamber/ valve re-design caused delays. But a satisfactory solution was achieved a year later.
Their target was an international rally performance level to beat the Lancia Stratos. For a more detailed explanation of the X1/9 Prototipo see . Fiat's decision to use the commercially more acceptable 131 as a basis for their next rally weapon then meant the 16 valve head research was applied to the 131 Abarth's 2 litre twin cam instead.

The 131 SE031 Abarth here (below) in action during the 1975 Giro d’Italia (Tour of Italy) had a V6 engine derived from the Fiat 130 Coupe. The Giro d’Italia was a magnificent event open to race rally and fast road cars alike – using race circuits and stages all around Italy. In 1975 this 031 won the saloon category of the event with Giorgio Pianta the Abarth test driver at the wheel (later also manager of the Abarth and then Lancia World Rally team efforts).
Prototipo 131 031 Abarth on the 1975 Giro d'italia
The 131 body was a good choice for development, with a wide enough engine bay and rear wheel drive. The car's massive tyres were very necessary! Earlier in the 1975 season Pianta had tested the car commenting on the car's lack of stability at high speed. The Fiat V6, derived from their exploits with Ferrari and the Dinos, was designed as a cruiser rather than a motorsport engine and although providing plenty of mid-range torque has been commented on by other drivers as lacking a top end. In the 031 the engine was fitted with triple IDF Webers.
The combination of Mr. Pianta, 031 and Fiat's resources ensured a comfortable saloon class win - despite several reported suspension, oil and fuel consumption, and gearbox problems.
The 131 Abarth 031 1975 - Picture Courtesy of the Fiat Archive, Turin
The SE031 was built as Fiat stepped up their budgets for the rally teams in 1974-75. Its engine was based around the type 130 B.000 in the Fiat 130 Coupe (produced between 1971 and 1977). In standard trim this was a V6 (60 degree) with bore and stroke of 102 x 66mm and 3235cc capacity, generating 165bhp DIN at 5,600rpm. Its fuel consumption was just over 19mpg. Which just about left it doomed following the oil crisis of 1973/4.
For the SE031 the blocks were bored out to give 3.5 litres with a special triple IDF Weber inlet manifold, and racing exhaust manifold (as seen in the picture) with a short 3 into 1 exhaust on either side. This engine generated 270bhp at 6800rpm.
....With its rasping V6 exhausts, it was a very noisy car!
The next 131 prototype - the 131 035 Abarth was fitted with an early Volumex supercharger based on a 16valve 1995cc Twin Cam. The capacity of the engine was also varied according to the regulations for its intended class. In the first instance the car was tested with a 1995cc capacity engine, but to keep within the 'under 2 litre' motorsport categories, forced induction engines carried a capacity penalty - so the capacity most often quoted for the 035 is 1452cc. This car also sported streamlined lightweight panels, and the car produced 290bhp with a top speed of 175mph. Made in 1979, it was entered for practice in the 1980 Le Mans 24 Hours race – driven by Pianta, but was not entered for the race itself. This was not as odd as may first appear, as it was relatively easy for Abarth to take the car, amongst the Lancia transporters and the Beta Montecarlos entered for the event for additional testing with the team already on hand.
The 035 also stands astride two eras in Abarth history. It was clear to the designers that the next generation of world rally winners would need a 50%  power increase from the same capacity engines - as it looked very likely that the performance loop-hole of using the old Group 4 rally/sports prototype category would continue in some form. This inevitably would mean using forced induction.
Within the Fiat Group there was a debate about the means to achieve this. But as so often within the Group there was a political as well as engineering dimension to all of it.
Following the Stratos years, Lancia had been excluded from competing in the world rally series while the Fiat 131 Abarth was 'in play'. Instead Lancia chose to build its brand by entering the Sports and Endurance world race series. In going head to head with the likes of Porsche, some of these Lancia sports-racers used naturally aspirated engines, while some successfully adopted smaller capacity engines with turbochargers. Furthermore, in 1981, Lancia's motorsport team found a sponsor in Martini who's distinctive livery and commitment was to last over a decade.
So the debate over performance and reliability for the next world rally winner was between Abarth and their Volumex supercharger design, and Lancia with a form of the KKK type turbocharger familiar to their race team. Some technical doubts over the durability of the turbo and engine management coupled with a bigger Works design of Volumex supercharger meant Abarth won the design debate. However it was to be installed in the Lancia 037 in 1981/2 - also the Abarth SE037. For more detailed discussions of the 037 see the Lancia 037 Model page. Abarth pulled together all their experience from the X1/9 prototipos, with a similar mid engined rally car design, to ensure the 037 was readied in record time. The two cars, the Fiat 131 035 Abarth, and the Lancia 037 Abarth represent the link between the normally aspirated Fiat twin cam and the Group B Lancia turbocharged 4 wheel drive eras. It was also the last two wheel drive World Rally Champion rally car.
Engine Twin cam belt driven
4 cylinder in line, 1452cc*, 7,8:1 compression
82mm bore x 67,5mm* stroke 
[*capacity was varied during its life]
16 valve dohc head 8 valves per cam
Output 290bhp DIN @ 6400rpm
Fuel Injection with Volumex charge compressor
Lubrication: rotary pump dry sump cap. 5.1kg radiator cooled
Coolant: pump, thermostat & electric booster fan cap 7.5li
Ignition Coil and distributor electronic trigger
Fuel Tank capacity 13 gals
Gear box: 5 speed top speed 174mph
Suspension Front: McPherson strut type, coil springs, with lower wishbones, longitudinal tie rods
Rear: independent wishbones with trans
Brakes Front: disc,
Rear: disc,
Steering Rack and Pinion

Wheels/tyres Front:16ins 255(10-50)/50 Rear: 16ins 295(13-60)/50 
Pirelli on special Abarth spilt rims
Length 4268mm
Width 1900mm
Height 1350mm
Wheelbase 2490mm
Track Front:1500mm Rear:1560mm
Weight 1020kg unladen

131 Abarth - the Cars
So when the call came from Fiat to prepare the 131 for World Rally winning, Abarth already knew a lot about the chassis, the car and its components. They were well down the road to achieve an outright winner. The body work for the 131 Abarth was designed by Bertone, using similar weight saving techniques they had practiced with Abarth on the X1/9 Prototipo. Thin GRP-fibre glass panels were used extensively, with perspex side and rear windows. The roll cage was kept to a minimal design, commensurate with its stiffening task. And these first attempts to reduce the car's weight achieved a tarmac event weight of 973kg. This is over 65kg lighter than the standard 131 Sport, but with the extra guards and heavier duty suspension mounts/equipment on gravel rallies, this weight goes up to 1028kg.
A comparison with the Stratos power to weight figures is revealing, showing that in this important area, the 131 was in fact inferior to its 1973 sister car.
In the early cars, the spring rates were in fact the same for both tarmac and gravel versions, it was the length of travel that differed according to the event. 7inch wide wheels were used on gravel rallies, except for the 6inch used on ice, and a variety of sizes used on the tarmac rallies, exploiting the split rim design to provide a range of widths up to 12 inches. Typically, for tarmac stages, the Works cars would run 10inch fronts and 11inch rears, depending upon the driver's preferences.
The brakes were based around 12inch front and 10inch rear rotors, with twin rear calipers - the car having an additional hydraulic handbrake set. The gear box was a crash design (reduces the power loss in this era) with two sets of ratios homologated. Both were close ratio specs. There were also eight final drive options available, ranging between 6.6:1 and 3.9:1, also ZF supplied a limited slip differential.
The Kugelfischer mechanically injected 1995cc engine produced between 205bhp and 210bhp at about 8000rpm - depending on the exhaust manifold and cams chosen. With a compression ratio of 8:1 Abarth recommended a rev limit of 8500rpm!
Homologation into Group 4 of the Rally Championship required 400 road versions of the 131 Rally to be made. Lightweight body panels had been designed by Bertone who were given the assembly task too. In rally form the shell was some 50kg to 75kg lighter than standard – depending on the spec. for the particular rally. Abarth used the stiffer 2 door saloon. And in March 1976, all the preparations were complete.

The homologation (or Stradale) road version had the following general specification:

131 ABARTH Spec (homologation road spec)
Jonathon Sage's 131 Abarth 04
Engine 138 AR1.000 Twin cam belt driven
4 cylinder in line, 1995cc, 10:1 compression
84mm bore x 90mm stroke
16 valve dohc head 8 valves per cam
Output 140bhp DIN @ 6400rpm 18 mkg @3800
Lubrication: rotary pump sump cap. 4.1kg radiator cooled
Coolant: pump, thermostat & electric booster fan cap 7.5li
Carburation Weber 34 DMTR 51/250
Ignition Coil and distributor electronic trigger
Fuel Tank capacity 11 gals, d.c. pump
Gearbox 5 speed Colotti cogs Fiat assembly, clutch: single dry plate
Final Drive Cylindrical screw, 14/50 ratio
Suspension Front: McPherson strut type, coil springs, with lower wishbones, longitudinal tie rods
Rear: independent wishbones with transverse leaf spring & telescopic shock absorbers
Brakes Front: disc, single piston & swing arm caliper
Rear: drum
Steering Rack and Pinion
Weight 980kg unladen
Wheels/tyres 14ins 185/60 HR Pirelli
Cromadora 7J

So the road going version of the 131 Abarth included a 1995cc twin cam, with a 16valve head, but with only one twin choke Weber carb. This generated about 140bhp @ 6400 rpm with a maximum of 130 lb/ft of torque at 3800 rpm. A 5 speed box was used, and Abarth homologated * rear axle ratios between 7/43 and 11/40 for competition.
Power output from the Works Rally 131 was 215bhp @ 7000 rpm, with 166lb/ft of torque at 3800. As mentioned the Works cars also had a fully independent rear suspension, Kugelfischer mechanical injection, and a 5 speed ZF gearbox. This car won 3 of the next 4 World Championships in 1977, 78 and 1980.

131 Abarth Rally Spec (basic competition spec in 1977 season)
Engine 138 AR 000 Twin cam belt driven, Abarth type 236b
4 cylinder in line, 1995cc, 10.7:1 compression
84mm bore x 90mm stroke
16 valve dohc head, 8 valves per cam
Output 215bhp DIN @ 7000rpm 23 mkg @5600, max revs 8600
Lubrication: rotary pump sump cap. 6.6kg radiator cooled
Coolant: pump, thermostat & electric booster fan cap 7.5li
Carburation KugelFischer injection (mechanical trigger)
Ignition Electronic
Fuel Tank capacity 60 litres 13.2 gals, ext. safety cell, D.C. pump
Gearbox 5 speed ZF dog, clutch: single dry plate
Final Drive Hypoid, 8 ratios ranging from about 7/43 to 11/40
Suspension Front: McPherson strut type, independent wishbones, torque reaction bars coil springs, with lower wishbones, longitudinal tie rods
Rear: fully independent trailing & lateral arms, swinging half shafts & coil springs with telescopic shock absorbers
Brakes Front: 12ins disc, inc. ventilated, dual piston caliper
Rear: 10 ins disc with dual circuit system with balance pump front/rear
Weight 973kg tarmac configuration, 1028kg gravel unladen
Wheel/tyres 15ins with ranges of tyres inc. MS 35 185/70 15 or P7 285/35 VR 15
Cromadora 7J gravel, 10J front 11J rear tarmac
Body widths 1820mm – 1520mm front track, 1492mm rear track.
Early version engine notes
Compression ratio 10,7 to 1
Bosh - Kugelfischer mechanical fuel injection, first version had DCOE type throttle bodies and manifold.
Larger oil pan - 6,6 litres capacity
215 bhp DIN (158 kW) at 7000 rpm, 23kgDIN (225 Nm)  torque at 5600rpm
Oil cooler co-located beside radiator
Flywheel options 7,3kg with 230mm clutch
Nitrited crank Mechanical clutch
Abarth 84 mm pistons (part EM 939)
Abarth valve springs (part 06,131,83)
Abarth oil filter (part 90,131,00)
Cylinder head gasket 86,5 mm  (part EM 876)
Intake valve 35,5mm (part EM 937)
Exhaust valve 30mm (part EM 938)
Engine gasket set (part EM 952)
Electrical Notes (Magneti Marelli)
Battery was 12V-24Ah-150A (Part 6.FC.17)
Windscreen wiper motor (80 al m/´)  (Part. 5040704.1) 
Starter was 12V-1,2kW (Part 5023181.1)
Coil "Super Bobina" with resistor to 8000rpm (Part BZR.204.A)
Distributor Abarth spec. (Part S.144.PA)
Alternator, six diode 12V-1000W (Part 63303425)
Voltage regulator (electronic) (Part RTT.110.B)
Abarth spark plugs (Part 7024041)
Works 131 Abarth line Drawing - Courtesy of the Fiat Archive, Turin
More Notes:
Weight distribution was about 50%:50% (front to rear) with crew on board.
wheelbase 2489 mm
track, front 1461 mm
track, rear  1397 mm
length 4181 mm
width 1720 mm
height 1372 mm
ground clearance in gravel trim 216 mm
fuel capacity, "abarth" tank 59 litres 
Abarth built three different body strengths for tarmac, forest/gravel strength, and rough (Safari etc).
The weights vary accordingly; Early gravel models weighted 980 kg, late gravel models 1026 kg.
The heavy re inforced ones continued to get heavier each season.
The line drawing above shows the early style car layout - with the roll hoop behind the crew, and re inforcing the rear axle points only.
131 Works Performance Levels
With the later 230 hp engine and 4,88:1 final drive
0-30 mph
2,6 seconds
0-60 mph
6,6 seconds
0-100 mph
17,5 seconds
Top Speed
115mph @ 8000 rpm
Standing 1/4mile
14.6 seconds

131 Abarth Timeline
By October 1975 Bertone had mostly completed the preparation of the 400 131 Abarth needed for FIA Homologation into the Group 4 category of the world rally championship. 50 of these cars were earmarked and duly dispatched to Abarth for Works preparation (Preparazione Corsa). The aim was to achieve a fully rally competitive car later during the 1976 season.
The Works cars were developed in three states of trim/tune to meet the demands of the world's rallies, Snow and ice, Gravel and Tarmac. Although we might argue that the Safari Rally spec became a fourth special trim state later. They were not precise about the detailed spec of some of the cars - so you can find small variances in the specs on some of the photos of the time.
The homologation changes gave Abarth some flexibility in the car specs they used, so that aluminum paneled doors, perspex side windows, additional lighting configurations with big or small spot lights can be seen. The size and finish of the can also be from another spec, and out of place to the purist. So the wide wheeled tarmac cars extended arches can be seen on other than tarmac events.
I will continue to build on this timeline of modifications to the cars, when possible I have used the homologation dates - when unknown, I have used the time they first appeared in the rally cars......
& Bay
& Brakes
Body Trim
& Other
232 C engineColotti T209 with modsF:300mm rotor, 2x48mm pistons.
R:252mm rotor,
2x38mm pistons,
Hbrake drum inside
10k rpm rev counter, oil temp/ press, water temp, amps, fuel press/ level
Heuer twin watches & trip
Halda odometer trip
Steering fast lock 2.8 turns
Early roll bar behind crew (see image)
Manual trip extinguisher system
Mid/ late 76
4-2-1 exhaust manifold retained but exhaust modified throughout the seasons so split again into two rear boxes optional, and pipe re-join point variedColotti plus T247 gears.
CIMA casings and then gears adopted
New Pedal box/ master arrangement in bay
Lockheed 4 pot 38mm pitons F&R
Girling 4 pot 38mm
Hbrake on own disc with 31mm pot
Revised gear box housing for longer through gear stick
Matching transmission cover
Roof air intake filter
Sump guard access holes
Firewall modded
Type 163 CIMAboxF: Revised bearing housing & bottom joint
Revise top & bottom mounts with uniball bearings (all 4 corners)
Suspension arms increased
Steering arms & joints size increased
Turrets front and rear modified
Additional locks for bonnet and boot lids
Type 164 CIMA box
Type 165
F: 275mm rotor option
R: New H/brake layout
Revised front hub bearing shaft
Rack uprated
Slide plate throttles
15 litre oil sump in boot
Dry sump layout tested
Uprated triple oil pumps
11.0:1 CR 230bhp
Slide bearing revisionNew suspension postsSolid state Ignition
Type 168 CIMA
Revised top bearings and mounts for body attitude changeTurrets reinforced
Revised hydraulic Hbrake
Outboard oil pumps
Further ex. manifold options
Support tie bars for engine bay into carbureted and injected variants
Revised front arms
New lightsNew rear light size & cluster
Reinforced rear arms with ball joint shields New Dash gauges repositioned
Rear brake balancer
New struts front and rear (shock)
Travel limiter for front shockersReinforced body bracing for front suspension
ATE calipers & new hbrake calipers
ventilated front discs
F:274mm rotor
R: 254mm rotor
Triple action clutch pressure plate
 8 litre dry sump tank
New diff mount bracketRevised pedal box
New re inforced suspension arms
New integral hydraulic Hbrake into rear pots
131 2000 ‘Volumetrico’ - SuperMirafiori Volumetric Abarth - and the last of the Line.
During the Summer of 1980 FIAT presented two more 131 prototypes to the European motoring press. These were based around 'blown' versions of the earlier 131 Racing/ Sport having supercharged 1300cc and 2000cc engines producing 115 and 142 bhp DIN respectively.
The Abarth designed, positive displacement blower was belt driven and operated via a special Weber carburetor. This is a similar design to the supercharged versions of the 124 Spidereuropa and Lancia Beta Volumex but with a larger volume blower.
In August 1981 these “Volumetrico’ 131’s were launched with 7.6:1 compression engines, oil cooler, electric fuel pump, special exhaust and a completely upgraded suspension and brake package. Their Pirelli ‘Plus One’ wheels and oval exhaust tail pipe were similar to the early 130tc Strada Abarth. All cars were assembled and prepared at Abarth.
Other than the slightly lower ride height and rear ‘Volumetrico’ badges, there was little external difference to the standard SuperMirafiori series three. Except this one would take a lot more catching! Top speed was quoted at 101mph because of the 10/39 diff. ratio but, as with all the supercharged twin cams, the torque output was fantastic (21.8 mkg DIN at 3600rpm in comparison to the Rally 131 Abarth’s 18 mkg DIN!). 0 to 60 time is under 7 seconds.
Fuel efficiency of the 2 litre was 24 to 27 miles per gallon. This bares comparison to any tuned twin cam prior to the modern Weber/ Marelli engine management systems. Impressive!
The 131 2000 Supermirafiori Volumetrico Abarth - Picture Courtesy of Fiat Archive Turin

SFC Gallery
Rallies in Brief
The World Rally Championship was only just being formed under the FIA. It looks as though Lancia fully intended to run again in 1977 with the Stratos and had driver teams ready.
Fiat was the only manufacturer to announce its intention to compete in the 1977 WRC – which was for makes.
A separate drivers championship existed. Lancia along with several other manufacturers entered drivers for the newly established FIA Cup for Rally Drivers – the forerunner of the World Rally Drivers Championship. This series involved a mix of WRC world rallies, European and National rallies to provide a global spread of events – more extensive than the Championship for Makes. In the latter, Fiat planned to compete in all but one round - only excluding the Safari Rally from their campaign. Ford entered championship too.
Fiat’s driver partnerships at the start were:
Markku Allen & Illka Kivimaki,
Fulvio Bacchelli & Francesco Rossetti
Maurizio Verini & Ninni Russo
Plus Simo Lampinen driving when he wasn’t involved with Lancia or Saab.
Plus Makinen Salonen and Valtaharja in Finland
Walter Rohrl joined in Canada and Darniche & Mahe in the Fiat France car.
Lancia’s drivers entered the FIA Cup for Rally Drivers
Sandro Munari stayed with his Stratos in the FIA Cup.
Simo Lampinen & Andreasson completed the team.

WRC rounds 1977 in Monte Carlo, Portugal, New Zealand, Acropolis Greece, 1000 Lakes Finland, Criterium de Quebec Canada, Safari, Sanremo, Tour de Corse Corsica, RAC Rally GB.
Fiat wins the title.....
Monte Carlo - 22nd/29th Jan - saw Fiat Group enter 45 cars for the 45th Monte - after Alen was disqualified, and Bacchelli, Pinto, Darniche, & Rohrl all retired the Rally was won by Munari & Maiga in their Stratos. Jean Claude Andruet came second in a 131 Abarth (Fiat France).
Swedish - 11th/23rd Feb - two 800km stages with 34 special trials. Won by Stig Blomqvist's Saab, best 131 was Lampinen & Andreasson in fourth.
Portuguese - 1st/6th March - four stages 2,458km, and 46 special speed trials. Won by Alen & Kivimali with Andruet 4th and Verini 5th. Ford's efforts had been considerable too.
Safari - 7th/11th April - No Fiat entry, Lancia Stratos Alitalias of Munari & Sodano, Lampinen & Andreasson, plus Kenyans Ulyate & Street. Mitsubishis and Peugeot 504s were fancied but the Ford of Waldegaard and Datsun of Aaltonen & Derwes took top honours. Ford and Fiat were llevel on 48 championship points, Opel on 39 and Lancia on 32pts.
South Pacific (New Zealand) - 1st-7th May - mix of dirt/gravel, 'metal' and tarmac stages. The Fiat v Ford fight had Alen, Bacchelli, & Lampinen versus Vatanen, Marshall & Robson. bacchelli won with Alen third and Lampinen fourth. Fiat two points ahead on 66 (to 64 Ford)
Acropolis - 30thMay/2ndJune - Fiat entered 8 x 131 Abarths! and all major teams were present. Fiats suspect diff casing caused three official entries to retire Lampinen came fourth. Waldegaard, Clark (Fords) and Kallstrum (Datsun) were on the podium. Ford led by 4 on 82 pts.
1000 Lakes - 26th/28th August - Only Alen's was officially there as last year's 131 winner taken out by a sabotage boulder. Ford 100pts Fiat 94.
Quebec Criterion - 15th/19th September - 1500km with 543km of special speed trials. Allen, Lampinen and Rohrl in 131s. Salonen, Lampinen and Andreasson scored ahead of Clark. Ford 114 v Fiat 112.
San Remo - 4th/8th October - heavy Fiat Group entry for their home rally, but the French entry 131 of Andruet & Delferrier won with Waldegard 5th. Fiat led again by six points.
Tour de Corsa - 5th/6th November - Fiat & Lancia fielded 10 official entries. Heavy attrition could not deflect from the Darniche & Mahe win, with Pinto then Corello in the Stratos, Bacchelli and Vincent in fifth to block any heavy points scoring by Ford. Fiat had 136 points with Ford on 124 and Opel (64) and Lancia (60). Fiat were effectively world champions.
RAC - 20th/24th November - Three 131s officialy entered with two others by the Autonovo Oy racing team (Makinen and Liddon) and one for Fiat UK for Lampinen. Starting at Wembley and finishing at York with 3057km and 69 special speed trials. All the major teams entered. Waldegard snatched victory in the final stages. From Mikkola & Hertz (Toyota), then Brooks Clarke and Dawson all driving Fords.
Monte Carlo, Portugal, Acropolis Greece, 1000 Lakes Finland, Criterium de Quebec Canada, Sanremo, Ivory Coast, Tour de Corse Corsica, RAC Rally GB
Walter Rohrl on the 79 Accropolis Rally

WRC rounds in 1980 Monte Carlo, Portugal, Safari, Acropolis Greece, Codasur Argentina, Sanremo, Tour de Corse, Corsica, Ivory Coast, RAC Rally GB.
SFC Questions
Q Due to a considerable amount of sun damage to the fabric on the headrests and upper surfaces of my Abarth's interior I am now on the look out for a replacement interior, front and rear seats.
I'd prefer the genuine original items, (with red stripes to match the colour of my car!) but as these are going to be extremely difficult to locate does anyone know of a good trimmer, or supplier of decent period looking bucket/racing seats.
All (sensible) suggestions appreciated. Thanks, Simon
On Perspex and polycarbonate side windows..........
On a project tp build a replica works 131...........
Page Links
Parts and Advice
Middle Barton Garage   Tony Castle-Miller
158 High Street, Banstead, Surrey SM7 2NZ. 0208 642-8577 fax: +44 (0)1737-370091
Guy Moerenhout

Gozzoli   Via Claudia 211, 41053, Maranello MO, Italy. Tele/fax: +39 (0)536-941240

Vitto Elaborazioni   Via Strada dei Frati, 12 36015 Schio Vicenza, Italy

Gruppo Ricambi BIELSTEIN OHG , D-31157 Sarstedt, Tel.: 0049 (0)5066 3074, Fax: 0049 (0)5066 65390 
e mail: 

Scorpione Abarth parts, Sleedoorn 10, 7873 CS Odoorn, Holland Tel: 0031 (0)591 513896 Fax: 0031 (0)591 513896 

Rinaldi Tuning , NL-7553 DJ Hengelo, Tel./fax: 0031 (0)74 2425129

Scuderia Topolino Dutch and German based Abarth supplier - Paul van Heyden 

Dichtungen-Schwarz Seals and Gaskets for the Abarths and similar classics if the are listed|: 
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