Renault 11 Turbo

MobileArt Mobile Video

MobileArt Mobile Rally Wallpaper










Gp A Renault 11 Development

 

Martin Sharp CCC August 1987

BRAKING AND ENTERING - Renault 11 Turbo's Corsica 1987

How rallying’s forgotten rally team turns the Renault 11 Turbo from hatch ordinaire to tarmac supercar

Renault 11 Turbo - Corsica 1987

 They were hardly sweating. Drivers arriving at the time control at the end of the narrow main street of the hilltop village of Borgo were breathing nearly normally. The stage used to be a traditional Tour de Corse ball-breaker before the Bastia parc ferme on the first night. It ran 42.29km from Ponte Rosso to Borgo, but FISA forced it to start this year from 29.10km away in Canavaggia.

Michel Perin, Francois Chatriot’s faithful co- driver in the second works Renault 11 Turbo, explains the change: "In the years before, when we got to Bastia – and to the Calvi halt after the second leg – we were completely and absolutely, ’ow you say? tired. Now is no problem, it’s cool, I think we shall have a good dinner tonight."

Cool now carries the same hip connotation in French as it does in English. It’s the most recent Franglais to join sandwich and le weekend. This year’s Tour de Corse was cool.

Perin’s brow just glistened, his overalls only damp. Cool. And no better word could describe the professional attitude and experienced dedication exhibited by the works Renault team in Corsica. The Tour de Corse is also known as the Rallye de France. It’s a round in both the World and French Rally Championships. This is its 31st year, and French rally cars have won the event 16 times. If you include the beautiful Alpine Renaults, Renault has won the Tour De Corse 13 times.

Jean Ragnotti’s magnificent 1985 victory in the Renault Maxi 5 Turbo against daunting 4wd Group B odds is fixed in many a memory. He also won in 1982, and he’s here this year, this time with a Group A car. But, rather like comparing a Lancia Delta S4 or Peugeot 205T16 E2 to the Maxi 5 Turbo, the might of machines like the Sierra Cosworth and BMW M3 makes the on- paper tarmac potential of his Group A Renault 11 Turbo look lean.

But this light little Renault can trip tarmac lights at remarkable, if not staggering, rates. Believe this: the first special stage of the third leg of this year’s Tour de Corse was exactly the same as previous years. It ran for 28.77km from Notre Dame de la Serra to Point Cinque Arcate. Last year Bruno Saby won the Tour de Corse in his tarmac – sorry, Corsica – specification Evolution Two 205T16; a car at the pinnacle of turbocharged Group 8 mechanical magnificence. That year he was also fastest on the Notre Dame de la Serra to Point Cinque Arcate test.

Bruno Saby needed 17 minutes and 38 seconds to thrust his 4wd E2 T16 over this 28.77km test. This year ’Jeannot’ Ragnotti hurled his 1419cc, carburettor-and-tiny-turbo engined fwd Renault saloon car fastest over those 28.77km. It took him 18 minutes and eight seconds – a mere 30 seconds more than Saby’s mega-tech 4wd supercar. How did we describe that temperature? And how can this ageing rally hatch be so rapid?

The Renault works rally team is a part of Renault Sport, but during Renault’s heady Formula One days it was constantly out of the management limelight – and budget approvals. Patrick Landon has been with Renault Sport since 1969. Eighty people worked there then. When he became boss in 1978 there were 14, but: "Those were good days, gradually building up strength and having successes."

In Corsica this year about 50 people helped the Renault Sport effort. Fifteen were mechanics. But everybody helped. General Director Bernard Casin handed spanners to mechanics. Renault Sport big boss and General Secretary of the entire Renault empire, Patrick Faure, was on hand at service halts, prepared to do exactly the same.

But enthusiam alone can be disastrous; success demands experience. If any team has experience of the Rallye de France it’s Renault Sport. It also has an arguably deeper grasp of its Group A rally car than any other team. In 1984 the team was rallying its Group B Maxi 5 Turbo, but Chief Engineer Francois Bernard also took on the task at that time of developing a kit which could convert the R11 Turbo into a Group A rally car which customers could use to win rallies, Bernard: "It was a small development with only 150bhp. We tried to make it a cheap kit, but in the end it turned out not so cheap!

"Then, at the end of 1985, the management said that we had to pull out of Group B and work on the Group A car. Management may have preferred that we used the Renault 9 or 5 GT Turbo, but I didn’t want to do that because the

"We have less than 180bhp, for sure. It’s not a joke – it’s impossible to have more from such an engine": Froncois Bernard, Renault Sport

 

cars are too small; it’s impossible to fit big wheels, coolers and exhaust, and the wheelbase and track dimensions are too small to have good control of the car. The 5 GT Turbo is a good car in Group N because it’s light, but it’s impossible to make a good Group A car out of it.

"So we worked on the 11 Turbo for about four months, and, yes, it was a critical four months – from mid-November to the end of February. Before then Oreille had rallied with it, but we had done little development."

The priority was to be competitive for Corsica in May 1986. "We completed the new gearbox in three-and-a-half months – all the drawings, gearing diagrams, castings, tooling, machining, assembly. We started on January 1, and the first time I tested the gearbox in the car was on April 15, and we had the new ’box for the Tour de Corse."

Although this Group A gearbox’s synchromesh rings have slightly different friction materials, they are essentially standard Renault parts. Gear strength and casing dimensions aren’t: "We changed the distances between the shaft axes to give us easier access to the internals. We also changed the tooth dimensions, but not the number of teeth, because there is only one set of gears homologated for Ihe Group A kit gear casing. But the ratios are good anyway, so we only changed the pinion dimensions. The gearchange linkage is nearly standard, but the rods have slightly different lengths, with a different universal joint which is closer to the ’box, and better quality bushing in the lever. But it’s very close to standard, with different lever ratios."

With such a comparatively old-fashioned engine design to work with, Bernard admits that if the team could have spent its development time on a different unit the car would have been faster. But this engine is well-known to the team; only its cylinder head is substantially different to that of the R5 Turbo.

Renault Sport’s Group A engines are built by Sodemo in France using Mahle aluminium pistons, TRW valves, Reinz gaskets and finely balanced French-built standard Garrett T2 turbocharger. Minor modifications are made to lhe cylinder liners to improve the cooling because the head is not as efficient as the Group 8 one, but the only trick bits are in the "very special" electronic ignition.

Bernard considers that using a computer to eliminate pre-ignition was: "The rnost difficult development. But we have less than 180bhp, for sure. It’s not a joke – it’s impossible to have more frorn such an engine. The car has no power, but we do have very good torque and the power band is very wide. Maximum power is at 6200rpm, but it’s quite the same at 5200rpm - the same power over 1000rpm, and the engine has a lot of torque from 3500rpm."

Being based closely on a comparatively simple production engine, the Group A car’s small turbocharger needs safety-changing during a rally. The carburettor has modified settings, but its standard seals adequately contain the pressure pushed through it by the Garrett T2, and will survive a rally.

 

But the tiny turbo spins very fast: "It runs at the maximum it can give us all the time, and spins at more than 200,000rpm. If there is a small balance problem then its bearing wears very quickly and the turbo fails – the smallest problem with the turbo and you can meet real problems: with no turbo this small engine is as flat as a pancake, so we change the turbo quite often. I have a little joke running with Gabriele Cadhringer (FISA’s technical inspector) – he marks all our turbo’s at the start, and after the rally I bring him a box containing all the turbo’s we’ve changed – he checks them – and they’re all standard parts; it’s only the balance which is done very accurately.

"We are prograrnmed to fit three turbo’s to the cars on the Tour de Corse, changing them before the parcs ferme in Bastia and Calvi. That’s because on tarmac they are often at maximum rpm and the drivers are rapidly on and off the throttle. In Porlugal, for instance, we only needed to change it for the last day.

"We have low power, but a very good power band, a very close-ratio gearbox, and therefore low top speed, so the car’s acceleration is quite good – but even so, its standing ’/4-mile time is hardly faster than a standard Peugeot 205GTI 1.9: our Group A R11 Turbo does the standing 400m in 14.90 seconds – the new 1.9 GTI does it in 15.05s. So to be competitive we have to make the car as light as possible with as high a cornering speed as we can get."

Group A class weight minimum for the 11 Turbo is 880kg. During a Tour de Corse spot check at the Corte regrouping, Ragnotti’s Renault tipped the scales just 6kg over that limit. To put that in perspective, Kenneth Eriksson’s class colleague Golf GTi 16v was 32kg heavier.

The R11 Turbo’s Matter-made bodyshells derive rigidity from an alloy roll-cage, but weight- conscious design is evident everywhere. Bernard: "We stuck with the standard steel fuel tank and location because it’s the lightest solution, and provides a better centre of gravity position in the car. We have homologated an alternative tank in the luggage deck, and we might use that in Greece, but a disadvantage is that we’ve moved the spare wheel forward, and with the tank inside the car it’s not as easy to get at the spare.

"In Greece we will carry two spare wheels – one behind the seats and one in the rear end, and with the tank in the luggage deck it’s not easy to get to them. I’m pretty sure that we will still use the standard tank on the Acropolis." They did.

Renault Sport fits very strong and light Kevlar tank guards to its gravel specification 11 Turbo, but retains an aluminium alloy front guard under all conditions: "Because it gives more strength to the subframe. The front subframe is just two rails without a crossmember, and. after two day s testing with Ragnotti using a Kevlar front guard, it’s completely finished. It is very important to the strength of the car to keep the aluminium sump guard because it’s a plate and doesn’t have plys, and using it still allows us to have a very light car."

Despite the car’s light weight, that comparative wimp of a powerplant means that, to be competitive, a rallying R11 Turbo needs serious suspension to heip it corner quicker than most.

Renault Sport’s running gear tests for Corsica began in March. A supplementary tarmac suspension solution was developed with stiffer springs and slightly different shock absorber rates. Bernard wasn’t certain that these new settings would be retained for Corsica, so the team took parts for both systems to the Isle of Beauty. Recce tests proved that the original set-up was best, and the Renaults ran the rally on this system – which must be good; it’s exactly the same for Monte Carlo, Portugal and San Remo tarmac....

For gravel there is a minor modification to the front struts to accommodate bigger ball joints, and the front brake callipers are forward, because there is no need for air cooling ducts on gravel, and the leading callipers facilitate changing the steering rods and ball joints. For tarmac the calipers trail the struts take cooling air from wind tunnel-optimised ducts. Wishbone tube thickness’ differ, the geometry doesn’t.

A component part of cornering is braking: the more efficient and stable a car’s retardation, the quicker will be its elapsed time through a corner. And it’s a complete understatement to say that there are many corners in Corsica. The multitude of twists, turns and gradients on the roads of this island make a car’s braking performance critical to its Tour de Corse competitiveness.

Rally teams know this. All teams test braking systems specifically for Corsica. Some have more success than others. The Renault 11 Turbos completed the 31st Tour de Corse on one set of front discs. At service after the 30.92km Barchetta to Silvareccio special test the orange temperature sensitive paint on the front discs of Ragnotti’s Renault shone in the sunlight. There was a kaleidoscope of other paint blobs there too. All the paint splashes on Didier Auriol’s Sierra Cosworth front discs had changedcolour – some serious calories had been cavorting around the front of that big Ford.

The particular front suspension layout of the works R11 turbo’s dictates a different caliper to that specified in the customer kit. The customer caliper is an ex-Formula One unit. This won’t fit within the works car’s Gotti wheels, so the pre-1987 Tour de Corse factory cars were fitted with fist-type closed-back front calipers which had to be heavily machined to fit inside the wheels. These were light units, but not as efficient as those in the customer kit, and that machining made the factory caliper even more flexible.

Caabianca passes the stricken Renault before sliding into the crowd standing in the escape road

Renault Sport knew that the efficiency of the R11 Turbo’s brakes would be a major contribution to its competitiveness in Corsica, and so at the beginning of this year worked with AP Racing to develop a better front brake system. The flexibility of the old specification caliper was the main problem, and so Maurice Kissane, competitions boss of AP Racing, visited Renault Sport in January, taking along a couple of alternative calipers. One of these was "a very nice little caliper, which is very stiff, and which we have put in a few F3000 cars this year".

Kissane continues. "The earlier caliper was not inherently less stiff, but had lost a lot of rigidity by having about 4 or 5mm machined out of its back to fit the Renault’s wheel profile. The caliper I showed Francois in January is stiffer and shorter, and that’s what he chose to use. It’s a much neater open back caliper, with an H-bolt double fixing at the top of the pads. It fits his scheme of having leading gravel and trailing asphalt calipers quite nicely. We managed to get Renault Sport’s first set out for testing in late March, and we took a flier and made enough sets to do the Tour de Corse. Testing subsequently showed that it was a pretty good caliper, so they’re happy."

AP Racing has provided closed back, ’fist type’ calipers for most sorts of motorsport for many years: "Because they are stiff, neat and tiny. But a problem is that the enclosed top section picks up and retains heat from the disc, while an open back caliper design has less area to gather heat. This later design is easier to service, and in most cases sufficiently rigid – but achieving that rigidity means that the caliper must take up more space in the wheel.

"When we first worked with the Audi Quattro in 1980/81 we used a closed back type of caliper, developed from the racing type which had its hydraulic cross pipe inside the casing. We fitted an external cross pipe to the Quattro caliper – which was equipped with a ceramic coated heat sink. Asbestos plugs protected the pistons. Early T16 and RS200 calipers were the same. These later became bigger open back designs, using different pistons and different insulation’s, but still retaining the saddles at front and back for rigidity."

The Renault 11 Turbo’s pre-Corsica brake specification was an old-fashioned design, but it suited the installation because of the space problems between the top ball joint and the steering arm. its current F3000-derived Corsica caliper design is unique to this rally car. Although stronger, this caliper is a thinner section, and therefore saves weight. It is attached to the strut by Renault-designed titanium bolts, and the same non-heat conducting material is used for its pistons. The Renault’s rear brakes remain small solid discs with one-piece two-piston calipers.

That Chatriot and Ragnotti’s R11 Turbos were visibly quicker than the BMW M3s and Sierra Cosworth’s on the twisty bits of this year’s Tour de Corse special tests was to a large part due to the efficiency of this braking set-up. But Renault Sport’s rally team has yet to perfect its actuation.

The team found that the less powerful closed back caliper needed a servo to be at its best. Engineering a balance bar into the system was eschewed, because Bernard’s theory was to optimise the car’s braking curve to its available adhesion – similar to a road car. A restrictor valve reduces pressure in the Renault’s rear brake line according to pressure into the system, thereby approximating to retardation rate, at lever- adjustable levels. This produces a variable slope of deceleration against braking force at the rear, with rear pressure trailing off toward high levels of negative G.

It’s an ideal theory – for a road car which has to slow and stop efficiently aver a very wide range of G. A rally car’s brakes, however, operate most often at the top end of the braking spectrum, or are used to unsettle the car, so the sophistication of this rear brake line pressure variability is often redundant.

But the evident stability of the Renaults in Corsica indicates that the theory behind their brake layout is much more than just half right. Although a balance bar brake arrangement can only provide linear levels of pressure to the front and rear circuits, it does provide up and down pressure adjustment at both front and rear, while the Renault arrangement enables pressure adjustment to the rear only: it’s impossible to increase the pressure going to the front brakes. This can make it extremely difficult to set the balance of the car up properly, and indeed the team worked hard to optimise the 11 Turbo’s brake balance during the first leg of the Acropolis Rally, after Corsica.

Renault Sport has had experience with balance bars on the Maxi 5 Turbo, and has tried one on the R11 Turbo, but the linkage design of the type tried may well be the reason for the team’s lack of success with this system on the Group A car. Perfecting the Corsica specification brakes involved development of Formula One-style cooling ducts in the St Cyr wind tunnel, and the vacuum servo remained. But an hydraulic servo is under investigation.

Initial ideas were to plumb this into the power steering. The problem here is that there is no hydraulic pressure when steering straight, but development of a combination of this hydraulic booster and a tandem master cylinder continues.

At Renault Sport’s garage base in Corsica, Patrick Landon addressed the team just before scrutineering. He predicted that this year’s Tour de Corse was going to be a sprint event, and that it would favour experience. The team has the experience, but hardly a sprint rally car, yet started the 31st Tour de Corse as favourite to win. The day’s Figaro newspaper should have headlined ’Renault contre le tous’... after being garbled over Corsican phone lines it appeared as, ’Renault contre Lotus’!Francois Chatriot on 1987 Acropolis Rally

That Renault Sport didn’t win is entirely due to the law according to Dr Sodt, although Landon openly considers that the team made a mistake by not making contigency plans for a particular loophole in that law.

"Pas possible!" was the oft-heard cry at service after the fifth special test. Jean-Marc Andrie had driven his ’engineering’ car over the stage less than an hour before Jean Ragnotti. The sky was overcast, but the stage was dry-dry, and looked for all the world that it was going to stay that way. But the ’plane couldn’t get below the cloud to have that last look.

When Ragnotti’s R11 Turbo hit the hail storm it was wearing super-special experimental Michelin slicks – brought to the island just the previous Sunday for Jeannot’s exclusive use. These were a major advantage for him in the dry. And like greased skis on that bed of hail. The ensuing off and puncture cost him five minutes. He’d been leading up to then.

Landon echoed the team’s stoicism: "The rally isn’t finished it’s not terrible". And Jeannot ’the acrobat’ conclusively proved his point bymaking fastest time on four consecutive tests just before the regrouping at Corte. Then on the last stage before Corte he hit an electricity pylon, severely restructuring the 11 Turbo’s fragile front right- hand corner.

Service first to sort out that right-hand front wheel somewhere near where it should be, but serious straightening had to wait until before the parc ferme at Calvi. The corner was too crinkled to bolt in a new crossmember, Porta-Power pressing tactics had to suffice.

Seven stages remained. On its trick tyres Ragnotti’s almost-straight Renault was fastest on six of them. Ford decided to retire its top driver. Against the odds Renault Sport kept its cars going. Ragnotti’s 11 Turbo finished fourth, Chatriot’s immediately behind him.

At the Ajaccio victory ramp, Patrick Landon applauded hard in appreciation, with a heartfelt congratulatory smile on his face. Rally winner Bernard Beguin beamed back his recognition from the bonnet of his Prodrive BMW M3. It was a genuine emotion. Cool.




Corsica Specs

(Autosport May 14, 1987)

Three 11 Turbos were entered by Renault Philips Elf for Jean Ragnotti, Francois Chatriot and Alain Oreille; the first two prepared at Antony in Paris and the third by Simon in Avignon.

Specifications were all the same, with engines tuned to 1 bar boost which the team still claimed gave only 180bhp, the same as on Corsica last year. As in San Remo, the final drive ratio was 5.08:1 while the all-asphalt event gave a chance to run 299mm diameter disc brakes instead of the usual 280mm.

A small 47-litre fuel tank was fitted and 15in wheels were used. Tyres were 21/ 59/15 with six types of dry compound, four intermediate and one wet.

The only recent change in specification was the use of an air duct to draw air from the high pressure area under the bottom of the windscreen rather than from the front of the car. The cars weighed just over the class minimum of 880kg, while the team was serviced from six vans – a high number for Renault.




Results

Tour de Corse May 07-09 World Rally Championship for Drivers, and Manufacturers, round 5

Pos

Driver/Co-driver

Car

Result

1

Bernard Beguin / Jean-Jacques Lenne

BMW M3

7h 22m 30s

2

Yves Loubet / Jean-Bernard Vieu

Lancia Delta HF 4WD

7h 24m 38s

3

Miki Biasion / Tiziano Swiero

Lancia Delta HF 4WD

7h24m 58s

4

Jean Ragnotti / Pierre Thimonier

Renault 11 Turbo

7h 25m 11s

5

Francois Chatriot / Michel Penn

Renault 11 Turbo

7h 27m 05s

6

Marc Duez / Georges Biard

BMW M3

7h 37m 58s

7

Carlos Sainz / Antonio Soto

Ford Sierra RS Cosworth

7h 41m 16s

8

Didier Aunol / Bernard Occelli

Ford Sierra RS Cosworth

7h 44m 16s

9

Alain Oreille /Sylvia Oreille

Renault 11 Turbo

7h 50m 08s

10

Laurent Poggi / Jean-Paul Chiaroni

VW Golf GTI 16V

7h 52m 52s


Leading Retirements

R Bruno Saby / Jean-Francois Fauchille . Lancia Delta HF 4WD suspension SS10

R Shg Blomqwst / Bruno Berglund Ford Sierra RS Cosworth... withdrawn SS9

R Kenneth Erikksson / Peter Dickmann VWGolf GTI i6V .engineSS14

R Kalle Grundel / Terry Harryman ..... Ford Sierra RS Cosworth . accident SS1

R Bernard Danichei / Alain Mahe ....... Mercedes 190E 2.3-16... lost wheel SS1

R Guy Frequelin / ’Tilber’.............. Opel Kadett GSi 2 0 . engine SS4


Class Winners

Group N

1600cc-2000cc: Balesi Cinndini {Renault 5 GT Turbo). th57m02s

Up to 1150cc: no starters

1150cc-1300cc: Rondnlle’Trouche (Talbot Samba Rallye), 10h05m25s

1300cc-1600cc: Giov- anJSantoni (Peugeot 205GTI). 8h03m04s

Over 200cc: Albertini Pasquah (Alfa Romeo Alfa 75 Turbo). 8hO 1 m16s.


Group A

Over 2000cc: as overall

Up to 1150cc: no starters

1150cc-1300cc: de Fresquet,’Poetloz (Opel Corsa). 9h18m26s.

1300cc-1600cc: Labrot Cabaniols (Toyota Corolla). 9h04m55s

1600cc- 2000cc: Ragnotti/Thimonier.

Group 8: Leandri/Luigi (Samba Rallye). 8h07m10s


Rally leaders:

SS1-4, Beguin. SS5-10. Loubet.

SS11-24. Beguin Starters/Finishers: 95/35

Stage Analysis

1st

2nd

3rd

4th

5th

Ragnotti

11

7

1

1

 

Beguin

9

2

4

4

2

Saby

2

 

1

1

3

Aunol

1

2

3

5

4

Balesi

1

    

Chatriot

 

8

6

2

2

Biasion

 

4

2

3

4

Loubet

 

3

3

7

6

The Rally Story

Etape 1: Left A~accio iPlace d Austerlitz) on Thursday 7 May at 0800, withregrouping at Porto- Vecchio, Zonza and Corte arnwng in Bastia at 2000 a distance of 562 05km, including 9 stages (232 25km)

Etape 2: Letl Bastia on Fnday 8 May at 0900 with a regroup at Corte arnwng in Calw at i 800 a distance of 399.20km, including 8 stages (205.37km)

Etape 3: Left Calw Saturday 9 May at 0800 with regrouping twice at A]accio before arnving at Ajaccio (Place d Austerhtz) at 1630 a distance ot 405 77km including 7 stages (181 60km).

World Rally Championship for Drivers: Kanakunen, 37; Biasion, 35. Ragnotti. 29, Alen. 28, Rohrl. 27. Enksson, 21; Salonen, Mikkola and Beguin 20. Carlsson and Chatnot. 18, etc

World Rally Championship for Manufacturers: Lancia, r4, Audi.48. Volkswagen, 39. Renault. 35. Mazda, 34; Ford, 28. BMW. 20, Toyota, 15, Alfa and Peugeot, i 3. Subaru. 10, Nissan and Fiat. 4. Opel, 2