Audi Sport quattro S1 / E2 (Group B)

Published on: Jan 18, 2016 @ 16:21
Originally Published in: 2014 (old website)
(C) Jay Auger - website owner & author
Notice: Any form of duplication methods (including but not limited to copy/paste of text and screen capture) of the website's content is strictly forbidden.
Audi Sport quattro S1


In 1983, Audi had anticipated that they would not be able to rely solely on their traction advantage and overwhelming horsepower to win rallies for much longer. In mid-1984 their predictions rang true with the arrival of the smaller, purpose-built, mid-engined, and four-wheel driven Peugeot 205 T16. The quattro in comparison was large, front heavy, and suffered from crippling understeer in most driving situations. To fix this, most of the engineers at Ingolstadt proposed that they should design and build a totally new Group B car from scratch. However, Audi’s top brass was not keen to the idea since it would have given bad press to their flagship quattro model. Hoping to save face, the car had to be improved substantially but not replaced – the answer was to be the Sport quattro.



In hopes to fix the quattro’s handling woes, the Audi engineers proposed to shorten its wheelbase by 320 mm (12.6″). In theory, doing this should greatly enhance turn-in capabilities and also reducing weight in the process (which meant overall better performance). The project was approved and the quattro underwent a major overhaul to make it a more capable rally car.

technical view

Shortening the wheelbase on a car who’s engine sits over or forward of the front axle actually worsens weight bias towards a front-heavy vehicle. This was proven when the press got their hands on its first Sport quattro homologation model: it tipped the scales at 62.1% over the front axle compared to the old quattro which had 60%. However, the wheelbase being very short makes for a quicker turn-in and greatly reduces rear stability which, in the Sport quattro’s case, could offset its understeer issue if driven properly. This was no easy task as the drivers had to push harder and aggressively “flog” the car through the corners for this to take effect. It was reported that the car still suffered from terminal understeer in low speed corners and/or if driven too cautiously.

As such, there was only one good way to drive the Sport quattro S1: all out and constantly sideways.

The drivers had also complained of glare in the windshield of the original quattro so the engineers took the opportunity of the car’s redesign to address the problem with a very original solution: since the chassis had to be cut in half to shorten the wheelbase, they married the rear section of the quattro with the front section of the Typ-81 (Audi 80/4000) which had the windshield already set at a steeper angle, thus eliminating the glare effect.

ASQS1 engine.jpg

The new Sport quattro S1 also featured an upgraded all-aluminium 20V turbo engine capable of easily producing 450 BHP. However, it was also more “peaky”, making the most of its horsepower in the very high RPM range, which made it ever more difficult to drive on top of its already twitchy handling. This led Audi Sport to develop a closer ratio 6-speed transmission then later the Porsche-derived “PDK” unit to help keep revs high and shifts quick. This could provide substantial cumulative time savings over the course of a long and twisty rally stage where gear shifts are very frequent.


Some questionable decisions were however taken with the S1: one of which was the replacement of the lower air dam with a large angled sump guard. It is evident that this much harmed aerodynamics.

Even though it was much more powerful and technically-advanced than the previous car, the Sport quattro S1 was generally not well received by the Audi drivers; Michèle Mouton and Stig Blomqvist in particular had issues adapting to the new shorter quattro’s features which demanded a driving style not quite compatible with their own. In fact, Blomqvist would shun the S1 while he and Hannu Mikkola raked up points with the “long wheelbase” quattro A2 in the WRC. Blomqvist would win the 1984 driver championship with Mikkola finishing second, easily ahead of their competitors. That year, Audi would get the manufacturer championship back from Lancia. However, for Audi, even though the A2 netted them more consistent results, it was decided to exclusively field the Sport quattro from 1985 and on.


In early 1985, Peugeot continued its domination with the 205 Turbo 16 while the more powerful Audi Sport quattro S1 still struggled to match pace. More improvements were evidently needed if Audi had any hopes of retaining their championship or even winning at all. In but a few months time, Audi  Sport developed the second evolution of the Sport quattro with striking aerodynamic enhancements. It was the first time that rally engineers created a bodywork package aimed directly at gaining more traction with various spoilers and appendages, as opposed to just gaining stability. In doing so, Audi had created an iconic rally machine that instantly came to symbolise the very image of Group B in most people’s minds; the immortal E2.


This all wasn’t just for show as it is estimated that the aero package was able to generate up to 1,100 lbs (500 kg) of downforce at high speeds.

Much work was also done in conjunction to help the weight distribution of the car, as everything that could be moved in the trunk/boot area was relocated there; engine coolant radiator, oil cooler, transmission cooler, and even the alternator which was now driven by a small pump motor. The result yielded weight bias up to F51/R49% depending on the setup used. This procedure also much uncluttered the engine bay which allowed for quicker access to key mechanical components.

The engineers at Ingolstadt did not rest there as the 5-cylinder turbo aluminium engine was improved yet again. Much of the work was concentrated in making more torque in the mid-range with the possibility of even more horsepower as well: as much as 590 BHP was reportedly used in that year’s Finland event. The centre differential was also “liberated” from its constant 50/50 ratio split with the use of a unit with a Ferguson Formula (FFD) viscous coupling. This finally allowed a variable torque-split between the front and rear axles and much aided the car’s handling – especially on tarmac.

All the improvements of Audi Sport’s new beast were clearly seen in the year’s 1000 Lakes rally in Finland as the car had much smoother transitions in the corners and had an “urgency” to come back down over jumps. The E2 in the hand of Blomqvist set no less than 16 fastest stages times, ultimately finishing in 2nd place only 48 seconds behind event winner Salonen’s 205 T16.

Legendary rally ace Walter Röhrl, who played an important role in the Sport quattro E2’s testing and development, describes it as one of the most intense machines he ever got to drive: “With this car, you have to think two corners ahead […] finding the correct balance between a decent pace and outright speed was a big challenge.”, he fondly recalls. Röhrl, unlike some of his teammates, was more than willing to adapt his driving to the car’s indomitable demands and gave the E2 a convincing win at the 1985 Sanremo rally – which ultimately turned out to be its only WRC victory. This amazing effort has since been immortalised in modern popular culture with a well-known animated gif:


In contrast, Stig Blomqvist still didn’t like where Audi was going with the car and, before the end of the season, had already signed up with Peugeot for 1986. That career move infamously led Audi to put him on the sidelines for the rest of the 1985 WRC season. Blomqvist stated years later that his perfect Group B rally car would have been a “long wheelbase” A2 quattro but with the E2’s very much improved and brutal mechanical components.

Sadly, Audi’s efforts at keeping the quattro a contender for the titles was to be in vain as the Peugeot 205 T16 still largely dominated 1985. This lack of success prompted some questionable decisions within Audi Sport, then led by Roland Gumpert, as they were accused of cheating in the year’s Ivory Coast Rally by allegedly switching Michèle Mouton’s badly damaged S1 with a chase car camouflaged to look like her own. Some insiders saw this as an act of desperation by Audi to keep the quattro competitive at all costs. Albeit it was never proven, Gumpert lost his position within the company soon afterwards.

To make matters worse, Lancia unleashed the infamous Delta S4 at the end of the season which immediately brought the Italian team successive victories. For 1986, Ford was on its way with the technically-advanced RS200 and the level of competition would show no sign of letting down from other rival manufacturers. Even though Audi was planning a rumoured 1,000 BHP version of the Sport quattro, all rally insiders agree that no amount of extra horsepower in such a car would have made Audi get its domination back.

Ultimately, the Sport quattro E2 would participate in only six WRC rallies before Audi decided to pull out of Group B rallying due to the spectator deaths at the 1986 Portugal event. For Audi’s top management, this unfortunate accident gave them a perfect way out of an unsavoury future in the WRC while somewhat saving face at the same time.

Although Audi would never admit it publicly, the quattro was a road car that was capable in rallying only due to its initial four-wheel drive traction and power advantage. However, unlike the Peugeot 205 T16 and Lancia Delta S4, the quattro obviously wasn’t a purpose-built rally car designed from scratch. The Sport quattro was a somewhat desperate attempt from the engineers to push the platform way beyond its natural capabilities. Audi Sport knew this and had secretly started developing a mid-engine “silhouette” version of the quattro. When Audi’s top management found out about what would later be revealed as the “Gruppe S project“, it was killed on the spot because they thought it would give their current road-going quattro and flagship model a negative image in the public’s point of view. This arguably was what truly made Gumpert lose his position with the company since he was one of the instigators of this secret project.

Audi later contended that Peugeot and the others “cheated” the “spirit of homologation” by building specialised rally cars from scratch rather than using a standard road going model as its base. Basically, call it German pride. However, this does not diminish the importance that the quattro played in shaping the automotive & rallying world. The fact that it stayed competitive for so long is a testament to Audi’s motto “Vorsprung durch Technik” (advancement through technology).

Everyone will forever fondly remember the quattro’s exploits and the unmatched spectacle of the Sport quattro E2. It may ultimately not have been the fastest around a rally stage but it was certainly the most exciting rally car to see and hear. Group B’s legendary status would be much less known and appreciated today if not for this very car.

Rohrl S1 E2.jpg

The Sport quattro’s story did not however end there as Audi also built a special version of the car based on the E2’s aerodynamics specifically for the 1987 Pikes Peak hill climb event: a gambit to try and make the quattro a winner one final time in the dirt (you can learn about that very special car by clicking HERE). In the end Audi Sport was successful at Pikes Peak, giving the model one last hurrah before switching their motorsports aspirations to the IMSA circuit.

The Audi Sport quattro E2 is an enduring legend most synonymous with Group B rally in popular culture, also being one of the most replicated models of the category by today’s enthusiasts, proving that unlike other racing cars that have disappeared from memory, this one never will!

To learn about where the twenty original works E2 that were built by Audi Sport may possibly be now, please CLICK HERE.


Group/Class B/12 Homologation number: B-264 (click # to view the papers)
Years active
  • (S1) 1984~1985
  • (E2) 1985~1986
Homologation start:

  • May 1st 1984 (S1)
  • July 1st 1985 (E2)

Homologation end:

  • December 31st 1990
Type I-5, DOHC 20v, gas engine located front longitudinal with 27.5right inclination
Displacement 2135 cc WRC: x 1.4 = 2989 cc
Compression ratio 7.5:1
Output power – torque
  • (S1) 400~450 HP @ 7500 rpm
  • (E2) 450~590 HP @ 7500~8000 rpm
  • (S1) 340 lb-ft @ 5500 rpm
  • (E2) 405~435 lb-ft @ 5500 rpm
Materials block: aluminium cylinder head: aluminium
  • KKK K27 turbocharger
  • air/air intercooler with water injection
  • Bosch LH-jetronic multipoint electronic fuel injection
Boost: N/A
Ignition electronic / firing order 1-2-4-5-3
Cooling system water-cooled  (E2) radiator moved to trunk area
Lubrication system dry sump with oil cooler
Type four-wheel drive
  • (S1) 5 or 6 speed manual gearbox
  • (E2) 5 or 6 speed manual gearbox
  • (E2) 5 or 6 speed “PDK” power shifted
Gearbox ratios (S1)

  • 1st: 3.500
    2nd: 2.083
    3rd: 1.368
    4th: 0.962
    5th: 0.821
    R: 3.500


  • 1st: 3.111
    2nd: 2.273
    3rd: 1.706
    4th: 1.318
    5th: 0.962
    R: 3.500

  • 1st: 3.111
    2nd: 2.273
    3rd: 1.706
    4th: 1.318
    5th: 1.125
    R: 3.500


  • 1st: 3.000
    2nd: 2.000
    3rd: 1.526
    4th: 1.167
    5th: 0.963
    R: 2.875

  • 1st: 2.700
    2nd: 2.083
    3rd: 1.706
    4th: 1.428
    5th: 1.217
    6th: 1.040
    R: 3.455


  • 1st: 3.500
    2nd: 2.273
    3rd: 1.706
    4th: 1.318
    5th: 1.04
    6th: 0.889
    R: 3.455
Differential ratio (S1) front and rear:

  • 3.875
  • 4.571
  • 4.857
  • 5.286
  • 5.857
  • (1985): 5.571

(E2) front and rear:

  • 3.875
  • 4.571
  • 4.857
  • 5.286
  • 5.571
  • 5.857
  • 4.375
  • 4.625
  • (S1) 100% locked centre differential with two outputs, 1st to hypoid spiral bevel gear, limited slip front differential homocentrically through secondary hollow shaft of gearbox, 2nd to hypoid spiral bevel gear, limited slip rear differential
  • (E2) output from secondary gearbox shaft to open or locked or limited slip centre differential with two outputs, 1st to hypoid spiral bevel gear, limited slip front differential homocentrically through secondary hollow shaft of gearbox, 2nd to hypoid spiral bevel gear, limited slip rear differential.
  • From rally Finland ’85+: Torsen centre differential with Ferguson Formula viscous coupling and adjustable torque distribution 20%-80% to 80%-20% front to rear automatically
  • (S1) dry – single plate
  • (E2) dry – double plate
  • (S1) steel monocoque Typ-85 chassis version of VW B2 platform, shortened by 320mm with roll-cage. Typ-81 front end and windshield frame. Front steel subframe. Steel doors. Kevlar bodyshell with composite front and rear bonnets, roof, and bumpers covers.
  • (E2) + Aerodynamic spoilers to the front and rear of the car to increase downforce. Wide arch bodywork with side rear air inlets to cool trunk mounted radiators.
Front suspension McPherson strut with lower wishbone, coil spring, gas shock absorber and anti-roll bar 19-22-25-28mm diameter
Rear suspension McPherson strut with lower wishbone, 1 longitudinal radius arm, coil spring, gas shock absorber and anti-roll bar 19-22-25-28mm diameter
Steering system rack and pinion with hydraulic power assistance 12.4:1
  • front/rear ventilated rotors 280/295mm diameter with 4 aluminium piston calipers (Lockheed or Girling)
  • 1985+: front ventilated rotors 304/330mm diameter, rear ventilated rotors 304mm diameter
dual circuit with servo

  • (S1) 4160 mm (163.8 in)
  • (E2) 4240 mm (166.9 in)

  • (S1) 1817 mm (71.5 in)
  • (E2) 1860 mm (73.2 in)

  • (S1) 1340 mm (52.8 in)
  • (E2) 1344 mm (52.9 in)
wheelbase: 2224 mm (87.6 in) front track:

  • (S1) 1465 mm (57.7 in)
  • (E2) 1520 mm (59.8 in)
rear track:

  • (S1) 1490 mm (58.7 in)
  • (E2) 1502 mm (59.1 in)
Rims – tires front and rear

  • (S1) 7″~9″ x 15″ or 16″
  • (E2) 7″~9.75″ x 16″
Dry/Unladen Weight
  • (S1) 1100 kg (2425 lb)
  • (E2) 1090 kg (2400 lb)
Bias: (E2) F 51~53 / R 49~47% (depending on setup)
  • (S1) 2.5 kg/HP (5.4 lb/HP)
  • (E2) 1.8~2.0 kg/HP (4.0~4.4 lb/HP)
Fuel tank 90~120 litres


Audi Sport quattro

Produced at only 224 units, about 160 of which were reportedly sold to the public, the Sport quattro is one of the most coveted and expensive Audis of all time. It was Audi Sport’s gambit at turning the quattro into a more competitive Group B rally car, which resulted in an amazing homologation special. It sported a much shorter wheelbase (12.6″) than the normal quattro plus using the steeper 80/4000 model windshield. Its turbocharged five-cylinder behemoth was tuned to produce a hefty 302 BHP in street trim which officially makes it the most powerful of all the four-wheel drive Group B homologation road cars that actually competed in the WRC (all other rally specials were closer to the 200 BHP mark in street trim).

At the time of its production, the Sport quattro was the most expensive Audi model in the dealerships by a very large margin: costing around 200,000 German Marks. Yet, it was reported that the car was a handful to drive fast and suffered from terminal understeer due to a nose heavy weight distribution (62.1%). Legendary American rally driver John Buffum, even though he was very familiar with the quattro & Sport quattro by clinching multiple wins for Audi in the North American rally scene, infamously crashed one in a Road & Track special feature.

It is note to mention that the official designation of the homologation model is the “Sport quattro”, while the “S1” actually refers to the rally evolution model itself. For more information about the correct spelling of Audi’s legendary car, CLICK HERE!


Class Sport Compact Homologation number: B-264 (click # to view the papers)
Production 1983~1984 (224 units) Assembly: Ingolstadt, Germany
  • I-5
  • 2.1 L DOHC 20v
  • gas engine
  • Front
  • Longitudinal
Compression ratio N/A
Output power – torque 302 HP @ – rpm 243 lb-ft @ – rpm
Materials Block: N/A Cylinder Head: Aluminum
  • turbocharger
  • air/air intercooler
  • Bosch multi point EFI
Boost: 17.4 psi (1.2 bar)
Ignition electronic  firing order 1-2-4-5-3
Lubrication system N/A Capacity N/A
Cooling system water-cooled
Type four-wheel drive 5 speed manual gearbox
Gearbox ratios N/A N/A
Differential ratios N/A manual locks on centre and rear differentials
Clutch N/A
Type steel monocoque Typ 85 chassis version of VW B2 platform, shortened 320 mm (12.6″)
Front suspension McPherson strut with lower wishbone, coil spring, gas shock absorber and anti-roll bar
Rear suspension McPherson strut with lower wishbone, 1 longitudinal radius arm, coil spring, gas shock absorber and anti-roll bar
Steering system rack and pinion with hydraulic power assistance N/A
Brakes N/A N/A
length: 4160 mm (163.8 in) width: 1860 mm (73.2 in) height: 1344 mm (52.9 in)
wheelbase: 2204 mm (86.8 in) front track: 1465 mm (57.7 in) rear track: 1502 mm (59.1 in)
Rims – tires N/A N/A
Curb Weight 1270 kg (2800 lb) Bias: F 62.1/R 37.9 %
Weight/power 4.2 kg/HP (9.3 lb/HP)
Fuel tank N/A
Drag coefficient 0.43



(free delivery worldwide!)

AWIN Affiliates Program – by purchasing books with the links provided here you are also helping to support the Rally Group B Shrine!*

 Group B – The rise and fall of rallying’s wildest cars (English)

Gruppe B Gruppe B – Aufstieg und Fall der Rallye-Monster (German)

Group 4 Group 4 – From Stratos to quattro (English)

Gruppe 4 Gruppe 4 – Das Jahrzehnt der Heckschleudern (German)

Traction For Sale: The Story of Ferguson Formula Four-Wheel Drive

WRC The Complete Book of World Rally Champions : All the Cars, All the Drivers 1974-2004

 Audi quattro – The Rally History (English + German)

 Rally Giants – Audi quattro

Audi quattro Rally Car: Haynes Enthusiast Manual

Audi quattro (German)

Audi quattro LM Audi quattro: The Complete Story

Audi quattro Gold Portfolio Audi quattro: 1980-1991

Audi Sport 30 30 Years of Audi Sport (English)

Audi Sport 30 30 Years of Audi Sport (German)

Audi quattro little The Little Book of Audi quattro

Audi quattro portfolio Audi quattro: Ultimate Portfolio

Audi quattro inside Audi quattro: The Inside Story of Your Car

(C) Articles by Jay Auger – website owner, main author and chief editor

  • Images & videos are the property of their original owners
  • All homologation papers are the property of the Fédération Internationale de l’Automobile (FIA): SOURCE
  • Eifel Rallye Festival pictures used under permission – McKlein Publishing