Audi Sport quattro S1 Pikes Peak (1987)

Published on: Jan 18, 2016 @ 16:32
Originally Published in: 2015 (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.

INTRODUCTION

It is no secret that Audi revolutionised rallying with the quattro and it was not long after that its potential was evident for the legendary Pikes Peak “Race to the Clouds” Int’l Hill Climb event. At the time, the track was mostly on gravel, which made Audi’s four-wheel drive system a natural asset. In fact, the quattro would become a winner six years in a row; 1982~1987 – three “Open Rally” class wins plus three overall wins and course records.


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HISTORY

Before we get to Walter Röhrl’s very special machine, let’s revisit the events leading to it: In 1986, Audi had abandoned their Group B WRC program early in the season due to the spectator deaths in Portugal and other safety concerns. However, some insiders stated that the truth was that Audi was under pressure from parent company Volkswagen to terminate its rally operations since they weren’t competitive any more. In any case, Group B itself was eventually banned at the end of the same year which would have netted the same result.

Audi Sport quattro S1 E2 (Group B)

Many people felt like the short lived Sport quattro S1 E2 didn’t achieve nor had proven its full potential, especially versus Audi’s arch rival Peugeot and their 205 T16. As such, Audi Sport prepared a very special version of their car specifically for the 1987 Pikes Peak race – to prove that the quattro can once again reign supreme. It was to be the ultimate iteration of the quattro. You could even say how the Group B quattro might have evolved into if given the chance.

S1 E2 (left) / Pikes Peak (right)

The Pikes Peak quattro did not have to adhere in any way to the then banned Group B regulations, as such Audi would thoroughly revise and improve on the S1 E2 unit that they had loaned to Bobby Unser’s for his record run of 1986 up the famed mountain. The car was then substantially carved about which allowed to lower the weight of the car to about a metric tonne (2,200 lbs) and improve the bias to near perfect balance (F50/R50%).

While the Peugeot engineers tried desperately to stretch the 205 Turbo 16’s wheelbase in hopes to gain more stability, which is usually more suitable to high speed courses such as Pikes Peak, Audi instead retained the same short wheelbase as the S1 rally model. However, the suspension itself was fully revised to even up the quattro’s handling and give the car a more aggressive rake to naturally improve downforce. Yet more stability and higher cornering speeds were achieved via major aerodynamic improvements such as adding “double stack” rear spoilers and a very iconic front spoiler.

For power, the car sported the same five-cylinder turbocharged engine found in the Group B rally model albeit again thoroughly revised by the engineers at Ingolstadt. Audi Sport stated that it had “officially” around 600 BHP which would put it at about the same power range than the E2 works car as used in the fast-paced 1985 Finland rally. The Pikes Peak engine however employed a much larger K28 turbocharger, making some insiders of the time to claim that the car realistically had closer to a thousand horsepower.

Pikes Peak engine

All of this speculating was put to rest when Walter Röhrl later stated in an interview that the engine actually had 750 BHP and that the throttle was like an “on/off switch”, partly thanks to the more aggressive “boost into exhaust” recirculating anti-lag system (ALS). Ironically, the all-out Pikes Peak engine was not married to the then top of the line dual-clutch, power-shifted, “PDK” transmission that were used on a few WRC Group B works E2s and retained the proven 6-speed manual transmission with Saxomat clutch activation on the gear lever.

In the qualifying sessions, the ultimate quattro was yet barely able to keep at bay the fleet of three similarly improved 205 T16s that Peugeot had entered in hopes to stop Audi’s reign at the event. On race day, the leading 205 driven by Ari Vatanen however encountered boost issues which gave Walter Röhrl the opportunity to set his record breaking run of 10:47.850 and be the first ever competitor to reach the peak under 11 minutes.

In the end Audi Sport won their gamble by giving the quattro one last hurrah – retiring the model from competition as a legendary champion. Audi’s motorsport aspirations thereafter shifted to circuit racing where they also dominated the scene early on.

Multiple replicas of the Pikes Peak quattro have since been built by collectors and enthusiasts, which can often be seen in demonstration events such as the Eifel Rallye Festival in Germany.

It is worth mentioning that the “quattro” model is correctly spelled with a small “q” which also can be used to specify the Audi four/all-wheel drive system. For more information about the correct spelling, CLICK HERE!


SPECIFICATIONS

Group/Class Unlimited (Open Rally) Pikes Peak Special Version
Years active 1987  # built: 1
Engine
Type I-5, DOHC 20v, gas engine located front longitudinal with 27.5oright inclination
Displacement 2110 cc
Compression ratio 7.5:1
Output power – torque
  • 598 HP @ 8000 rpm (claimed)
  • 750 HP @ – rpm (Röhrl statement)
  •  435 lb-ft @ 5500 rpm (claimed)
Materials block: aluminium cylinder head: aluminium
Aspiration
  • KKK K28 turbocharger
  • Bosch LH-jetronic multipoint electronic fuel injection
  • Recirculating “boost into exhaust” anti-lag system
Ignition electronic / firing order 1-2-4-5-3
Cooling system water-cooled
Lubrication system dry sump with oil cooler
Transmission
Type four-wheel drive 6-speed manual transmission
Gearbox ratios 1st: 3.179
2nd: 2.155
3rd: 1.580
4th: 1.214
5th: 0.977
6th: 0.825
F: 4.059
Differential ratio N/A Front, centre, and rear self locking
Clutch dry – double plate
Chassis-body
Type 2 door coupe steel/kevlar bodyshell with plastic front/rear bonnets and bumper covers. NACA style roof cooling duct. Aerodynamic “double stack” spoilers to the front and rear of the car to increase downforce. Side deflectors. Single seater and stripped down interior.
Front suspension McPherson strut with lower wishbone, coil spring, gas shock absorber and anti-roll bar.
Rear suspension McPherson strut with lower wishbone, longitudinal radius arm, coil spring, gas shock absorber and anti-roll bar.
Steering system rack and pinion with hydraulic power assistance 12.4:1
Brakes front/rear 4 aluminium piston calipers, front ventilated rotors 330mm diameter, rear ventilated rotors 304mm diameter dual circuit with servo
Dimensions
length: 4250 mm (167.3 in) width: 1860 mm (73.2 in) height : 1344 mm (52.9 in)
wheelbase: 2224 mm (87.6 in) front track : 1465 mm (57.7 in) rear track: 1502 mm (59.1 in)
Rims – tires front and rear

  • 16  inch
Michelin
Dry/Unladen Weight 1000 kg (2205 lb)  Bias Front/Rear%: 50/50 (claimed)
Weight/power 1.7 kg/HP (3.7 lb/HP)
Fuel tank N/A

AUDI RECORDS AT PIKES PEAK


VIDEOS


REFERENCES

(C) Article by Jay Auger – website owner & author

  • Images & videos are the property of their original owners
  • Eifel Rallye Festival pictures used under permission – McKlein Publishing
  • DISCLAIMER / LEGAL NOTICES

SPECIAL THANKS

  • Timo Witt – Audi Tradition

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