Porsche Engineering Magazine

Porsche Engineering Magazine

The PanameraStart/stop saves fuel

Resistance is futileHighlights of the 911 GT3

Staying on trackWheel development at Porsche

One day at seaAcoustics in a cruise liner

Issue 2/2009

Virtual realityDigital automotive development

One day at seaCabin development for a cruise liner

Resistance is futileEngineering highlights of the Porsche 911 GT3

Staying on trackReinventing the wheel every day at Porsche

Numerical simulation methodsThe Automotive Simulation Center in Stuttgart

The PanameraStart/stop saves fuel

Test strategies for vehicle systemsTo test or not to test – that is beyond question!

Engine developmentFrom inner conviction – the RS Spyder

Contents

5

Editorial

About Porsche Engineering

3

4

8

10

14

16

18

22

24

2

Editorial

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Discover for yourself why we have always“remained on track”.

With an eye to the future, we are alsocoming to grips with the latest challenges,such as creating the ideal network of elec-tronic components with the use of sophis-ticated test strategies. We will also revealto you how we will be making our productdevelopment process even more efficientin future, with the help of numerical simu-lation methods.

As you can see, we are designing the fu-ture for you, by developing new technolo-gies and questioning tried-and-testedapproaches. Accompany us on a shortjourney through the world of developmentand experience at first hand our day-to-dayfascination with our work and our under-standing of performance.

We hope you enjoy the latest issue of themagazine.

Dr. Peter Schäfer and Malte RadmannManaging Directors of Porsche Engineering

At Porsche Engineering we are well known for thinking

outside the box. This is because we focus on creating

the products of the future: on land, in the air or at sea.

In all areas of technology, we must take what is good and

improve on it.

Dear Readers,

The sea is a good introduction to themagazine, because in this issue wewould like to tell you about an excitingproject at sea where our engineers heardthe wind roaring in their ears. They wereworking on improving the acoustics inthe cabins of the largest cruise liner everbuilt in Germany and once again wereable to demonstrate their strength indepth.

Do you prefer your transport to be a littlesportier? Then we have just the thing foryou. The magazine also includes a de-tailed look at the development of thePorsche RS Spyder engine and an over-view of the engineering highlights of thePorsche 911 GT3. Or you can journeywith us to a completely new dimensionand discover the Panamera, the latestmember of our family.

You might think that with all these won-derful Porsche models around it wouldbe difficult for us to keep our feet (andour wheels) firmly on the ground, butthat’s not the case. Our wheel developershave been working on this for decades.

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At Porsche Engineering, engineers areworking on your behalf to come up withnew and unusual ideas for vehicles andindustrial products. We develop a widevariety of solutions for automotive man-ufacturers and suppliers, ranging fromdesigning individual components andcomplex modules to planning and im-plementing complete vehicle develop-ment projects, including productionstart-up management. What makes ourservices special is that they are basedon the expertise of a premium car manu -facturer. Whether you need an automo-

tive developer for your project or wouldprefer a specialist systems developer,we can offer both, because Porsche Engineering works at the interface be-tween these two areas. All the expertiseof Porsche Engineering converges inWeissach, but it is available all over theworld, including at your company’s officesor production facilities. Wherever we work,we bring a part of Porsche Engineeringwith us. If you would like to find outmore about the different areas of ourbusiness, please visit our website at:www.porsche-engineering.com

Impressum

About Porsche Engineering

Impressum • Porsche Engineering Magazine

EditorNicole Möller

Design: Machart–Design, StuttgartRepro: Piltz Reproduktionen, StuttgartPrinting: Leibfarth&Schwarz, Dettingen/ErmsTranslation: TransMission Übersetzungen,

Stuttgart

All rights reserved. No part of this publication may bereproduced without the prior permission of the pub-lisher. We cannot guarantee that unrequested pho-tos, slides, videos or manuscripts will be returned.

PublisherPorsche Engineering Group GmbH

AddressPorsche Engineering Group GmbHPorschestraße71287 Weissach, Germany

Tel. +49 711 911 - 8 88 88Fax +49 711 911 - 8 89 99

E-mail: [email protected]: www.porsche-engineering.de

Styling Visualization

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VR tools used in computer-aided engineering (CAE)

The quality of virtual prototypes is con-stantly being improved. At Porsche, vir-tual prototypes are at such a high levelof development that they can be usedas the basis for important process deci-sions. This saves both time and moneyand dispenses with the need for addi-tional materials for the production of real models. As a result, the use of re-sources and the environmental impactare also reduced, because technicalcomponents no longer have to be dis-

posed of, for example. In contrast tothe prototypes used in real-life crashtests, virtual prototypes also have alonger life.

The use of digital functional processesallows the potential for functional im-provements to be identified and exploit-ed at an earlier stage. For product styl-ists it is particularly valuable to be ableto put models into different scenariosand environments. In the case of tradi-

tional processes, this would involve sig-nificant transport and organization costsand the necessity for secrecy. Alongsideall the general benefits of using digitalprocesses in product development, overthe course of time a number of applica-tions have proved particularly valuable inthe different departments. While stylistsuse special software to develop models,design engineers choose different appli-cations with a different type of graphicalrepresentation and level of detail.

The digital automotive development process, optimized by Porsche, focuses both on

function and design. The result is the best possible combination of the benefits of

computer-aided engineering and virtual reality tools.

Styling versus design engineering

Virtual prototypes are used in both thestyling and design engineering process.However, in design engineering the datais presented in an abstract form whichgenerally only allows experts to inter-pret the results of the functional analy-sis quickly and accurately. In contrast,the photorealistic representation of stylingdata can be easily understood even bythose who are not experts on the sub-ject. If a decision-making process isabout to start which will involve the evalu-ation of both functional and stylistic fac-tors, it is often easier for the specialistsfrom the design departments to pres-ent their position clearly and thereforesuccessfully.

However, the use of different systemsin different specialist areas has the dis-advantage that the individual depart-ments only extract the data which isrelevant to their work. As a result, pos-sible synergies based on the combina-tion of functional and stylistic data can-not be fully exploited. For example, de-signers could test the vehicles they


6

ously analyze data from different digitalprocesses creates unique added valuefor engineers and stylists alike. The visualization software RTT DeltaGen allows the Porsche developers to bringtogether data for the functional analy-sis and the evaluation of the design sothat they can be represented in a waywhich is easily understood by everyoneinvolved. This makes communicationbetween the different departments con -siderably easier. Another positive im-pact of the new software application is

the fact that it visualizes products real-istically, so that complex, functional databecome comprehensible even to exter-nal people with no expertise in the area.For example, it is possible to highlightthe particularly positive characteristicsof new models by means of a virtual aero-dynamics analysis using visualizations.

New technology for new generations

The ability to present the latest tech-nologies makes a major contribution tothe brand image, in particular in the

Driving dynamics in real time – a direct comparison between the handling of two Porsche models

have designed by simulating them driv-ing past. The driving dynamics data whichwould make this possible are held by theengineering departments, but in the pastcould not be accessed by the designtools.

Networking digital processes

Porsche AG has identified a solutionwhich will overcome the problem of thedifferent objectives of styling and de-sign engineering and their systemslandscapes. The introduction of a com-puter environment which will simultane-

The virtual car in motion. Properties such as wheel forces which are not directly visible are indicated by arrows


7

Adding driving dynamics data or aero-dynamic information to realistic visual-izations of 3D prototypes makes theevaluation of the automotive designmuch easier. Test scenarios of this kindbring a new dimension to design evalu-ation, make complex data clearly visibleand increase the quality and the reliabil-ity of decision-making.

Looking to the future

The introduction of a standardized pres-entation and analysis tool at Porsche isone step towards a standardized digitalproduct development process. By tak-ing a modern approach, developmentissues can be resolved more quickly. In-terdepartmental communication and aninterdepartmental understanding of theissues involved allow the number of iteration loops to be reduced even fur-ther and time and money to be savedthroughout the entire vehicle develop-ment process. Simulation results can

now be used immediately in visualiza-tions. It may also be a significant benefitthat CAE and VR tools use differentprocessors (CPUs and GPUs) which areboth available as standard in PCs, re-sulting in no reductions in performanceon either side.

automotive industry, for example in thecase of current environmental issuesand hybrid technology.

The use of the RTT DeltaGen real-timevisualization software at Porsche allowsvehicle dynamics to be evaluated evenmore efficiently. The software has a verysimple interface which enables thecomponents in the design model to berapidly coordinated with the vehicle dy-namics model. In addition, the applica-tion can generate high-quality images inreal time. Camera settings on the vehi-cle can be changed during the virtualjourney and the driving simulations canbe viewed in real time, so that all the as-pects of the interaction between thehandling characteristics and the designcan be carefully analyzed. This gives thestylists a particularly good idea of howthe moving vehicle will look in real life.The option of presenting driving dynam-ics data using the design model can

also be made use of by the engineers,because the better and more realisticquality of the image also enables themto display their results effectively.

The visualization software is also usedto bring styling and aerodynamics intoline with one another. Porsche uses RTTRealFluid, the CFD (computational fluiddynamics) module of RTT DeltaGen, toevaluate the air flow behavior in the de-sign. RTT RealFluid enables simulationresults, such as the formation of eddiesaround the vehicle, to be presented inreal time in combination with the corre-sponding virtual design model. The rele-vant aerodynamic properties are shownin the form of virtual flow lines, intersec-tions or isosurfaces directly on the sur-face of the car. Different variants of thevehicle, for example with or without arear spoiler, can be evaluated at thesame time from both an esthetic and afunctional perspective.

Visualization on a real-time prototype

Realistic visualization of flow simulation data: Physical processes such as air flow distribution are made visible on the design model

Acoustics Meyer Werft

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Calm during the storm

Meyer Werft in Papenburg has beenbuilding high-quality ships for morethan 200 years. It has achieved a lead-ing market position by specializing indeveloping and building cruise liners.As in many other areas, in the case ofshipbuilding “Made in Germany” standsfor special products with very high qual-ity standards. Meyer Werft has commit-ted to meeting these standards and toproviding the highest possible levels ofquality. The main priorities in the designand construction of a cruise liner are to

fulfill the increasing demands for quali-ty, to satisfy the customer’s require-ments and to complete the project onschedule.

One of the passengers’ main require-ments on board ship is peace and quiet. Meyer Werft aims to meet thisrequirement and to identify areas forimprovement in order to offer cus-tomers the best possible noise insula-tion within the cabins and on the shipas a whole.

One day at sea

Porsche Engineering was tasked byMeyer Werft with analyzing the potentialfor improvement in the cabins. The proj-ect team joined the imposing CelebrityEquinox on a trial voyage in the NorthSea. The power produced by the shipwas enough to impress even the Porscheengineers. The liner is powered by en-gines with an output of more than50,000 bhp (the same as one hundredPorsche 911 GT2). The wind roared inthe engineers’ ears and it became clearto them that the situation when the shipis at sea is totally different to that in asheltered port. Heavy seas put the qual-ity and performance of the wall and ceil-ing joints and seals to the test.

Porsche Engineering optimizes the passengers’ cabins in

the Celebrity Equinox – the largest cruise liner ever built

in Germany.

Acoustics Meyer Werft

9

The experts from Porsche Engineeringused the latest measuring devices totrack down the sources of noise on the ship. These included an ultrasonicmeter, a near field probe and high per-formance microphones, an acousticcamera, loudspeakers, an endoscope,an accelerometer and a radio-controlledcamera system for inaccessible falsefloors. In the areas of the ship whichare particularly noise-critical, the engi-neers from Porsche Engineering trackeddown the problematical noise and lo-cated its source using the measuringdevices they had put in position.

The first stage involved measuring thecurrent noise levels in the cabins. Inorder to evaluate the noise transmis-sion between two neighboring cabins,the sound reduction index of the cab-ins was assessed. In accordance withthe ISO 140-4 standard, a standardizedsignal was generated using a sphericalloud speaker in the cabin and the soundlevel was measured using microphonesin the cabin itself and in the neighboringcabin.

The microphone signals were represent-ed in the form of third octave spec-trums. These indicate the effective-ness of the sound insulation and showwhich frequencies are particularly welldamped and in which areas there isroom for improvement. In order toevaluate the effect of the insulation ineach cabin, the microphones were po-sitioned in and around the cabin. Thedifference between two microphonemeasurements is the weighted soundreduction index “Rw”, a term used inarchitectural acoustics. This is the

were simulated using hydraulic presses.The cabins were gradually measuredand improv ed, every technical detailwas refined and a new concept wasdeveloped which would allow the ship-yard to produce lighter and more cost-effective cabins in future. New walland ceiling panels were developed byPorsche Engineering and the structuresof the entire cabin were optimized us-ing finite element analyses. The struc-tures were simulated and designed to

accommodate the loads to which theyare subjected. The result was signifi-cant weight savings and a cabin whichhas a much greater torsional strengthand also offers a better sound reduc-tion index.

The development project was highlysuccessful and the Porsche engineerscan be confident that all the passengerson board the Equinox will be able to en-joy peaceful and relaxing vacations.

measurement of the noise reductionbetween two neighboring rooms andbetween one room and the outside, forexample in the passageway.

Using their experience of developingsports cars and working on productdevelopment in many customer proj-ects, the experts from Porsche Engi-neering were able to identify usefulparallels and potential areas for im-provement.

All the proposed improvements high-lighted by the specialists from differentdepartments within Porsche, includingacoustics, materials technology andlightweight structures, were graduallyadded together. Reproducible resultsplay a particularly important role in the evaluation of the individual improv -ement measures. These results werepro duced in the next stage of the processusing measurements in a laboratoryen vironment where there is no noiseinterference of the kind which occursin a shipbuilding hall in a dry dock orat sea. There was absolutely no possi-bility of bringing the Equinox to thedevelopment center in Weissach fornoise tests, as she is 317 meters longand 37 meters wide and has a draft of8.30 meters, together with 1450 cab-ins. Instead individual cabins werebrought to Porsche Engineering onspecial trucks so that they could betested in a low-interference environ-ment. In special workshops the cabinswere welded to a specially erectedfloor or deck as they would be on boardship and were taken into use. Noisewas generated by powerful loudspeakersystems and the ship’s movements

The Meyerweft in Papenburg

Engineering highlights Porsche 911 GT3

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Porsche engineers are strongly opposedto any form of compromise and thisprinciple has been applied to the newPorsche 911 GT3. It produces morepower than its predecessor, but its fuelconsumption is comparable. The previ-ous models set very high standards inthis respect. The result of the develop-ment process is now ready to take tothe roads: a perfect synthesis of trackcar and everyday transport.

and forms a wedge shape to increaseits aerodynamic efficiency. The centerair intake is also highlighted by the jointbetween the apron and the spoiler lip.Its broad profile, which covers the fullwidth of the vehicle, contributes to thedownforce on the front axle. The addi-tional air outlet in front of the luggagecompartment lid has been completelyredesigned. It has two striking trimstrips and is fully integrated into thefront end. The large opening is an indi-cation of the high level of efficiency ofthe system for managing outgoing airfrom the center radiator and the addi-tional downforce on the front axle. The911 GT3 can overcome any resistance.

Porsche 911 GT3

You can develop a sports car on the basis of experience.

Or from the depths of your heart. We are proud to

present the new Porsche 911 GT3.

Resistance is futile

Significant changes have been made tothe aerodynamics of the new 911 GT3.The new front end is characterized byeye-catching, broad outer cooling air in-takes which give the new 911 GT3 apowerful appearance and provide thenecessary cooling air to the engine. Theslightly prominent center cooling air in-take reaches as far as the spoiler lip

Engineering highlights Porsche 911 GT3

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A perfect whole

The grilles in all the cooling air intakesrepresent another unmistakable high-light of the new 911 GT3. Their delicateyet robust mesh protects the radia-tors from damage and dirt and allowsfor a large throughput of air. The fixedrear wing is a traditional componentof all 911 GT3 models. The new shapeof the rear wing, which now stretchesbeyond the wing supports, is takenfrom the 911 GT3 RS and the 911 GT3Cup and 911 GT3 RSR racing cars.This gives the 911 GT3 a more racing-style wing design with increased effi-ciency which improves aerodynamicperformance and further increases thedownforce on the rear axle. The wingside plates are fully integrated into thewing profile. Other new design featurescan be found on the rear lid. These in-clude two additional ram air hoodsand a narrow black spoiler lip (gurneyflap) on the rear edge of the lower wingprofile. The scooped ram air hoods actas efficient air intakes to the engineand improve the supply of cooling airto the engine compartment. The addi-tional, highly effective spoiler lip cre-ates an air flow with a pronounced traileredge which contributes to the down-force on the rear axle.

Brakes, lift system and chassis

The standard braking system has beencompletely overhauled. The diameter ofthe front brake discs has been increasedfrom 350 mm to 380 mm (the rear brakediscs remain the same at 350 mm) and,for the first time, the 911 GT3 has com-posite brake discs. The front and rear

which makes the 911 GT3 even moreusable in normal traffic. An electro -pneumatic system can be used to liftthe body at the front axle via the PASMshock absorbers. The system is acti-vated by a switch in the centre consoleand, at speeds up to around 50 kilo-meters per hour, it raises the body atthe front by around 30 mm. The frontaxle ride-height lift system allows the911 GT3 to drive over ramps, entrancesand speed bumps in cities and resi-dential areas with much less risk ofgrounding.

Another highlight of the new 911 GT3is the central locking device for thewheels. The single high-quality anodizedcentral wheel stud which comes directly

discs are made of cast iron and thecalipers are made of lightweight alu-minum. These components are joinedusing several steel pins in a radial pat-tern. The use of aluminum allowed theunsprung weight on the front axle to bereduced by around 2.2 kilos. In the caseof the optional ceramic composite brake(PCCB), the weight reduction is 4.8 kilos.Additional brake air ducts for the rearbraking system are another new feature.They are located at the sides of theunderbody in front of the rear axle anddirect the cooling air onto the rear brakes.The result is an increase in braking per-formance under heavy loads.

One completely new optional extra isthe front axle ride-height lift system,

Technical data

Body

Drag

Engine

Bore Stroke Displacement Compression Engine performance Max. torque Power output per liter Maximum revs Power transmission

Performance

Two-seater coupé; fully galvanized, lightweight, all-steel monocoque bodyshell; full size and side airbags for driver and passenger. Drag coefficient cW = 0.32 Frontal area: A = 2.013 m2

Water-cooled, six-cylinder boxer engine; aluminum engine block and cylinder heads; forged titanium connecting rods; four overhead cams;four valves per cylinder; variable inlet and exhaust valve timing (continuous VarioCam); hydraulic valve clearance adjustment; four-stage variable intake manifold; dry sump lubrication; twin exhaust withtwo metal catalytic converters and two lambda sensors. 102.7 mm76.4 mm3.797 cm2

12.0:1 320 kW (435 bhp) at 7600/rpm 430 Nm at 6250 rpm 84.3 kW/liter (114.6 bhp/liter) 8500 rpm Six-speed manual transmission; drive via dual drive shafts to the rear wheels. Top speed: 312 km/h Acceleration: 0–100 km/h in 4.1 seconds 0–200 km/h in 12.3 seconds

Engine Porsche 911 GT3

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Cut-away image of the 911 GT3

1: Radiator module; 2: Central radiator; 3: Tandem brake booster; 4: Six-speed manual gearbox; 5: Separate engine oil reservoir (dry-sump lubrication); 6: Variable intake manifold; 7: Throttle valve (electronically actuated); 8: Coolant expansion tank; 9: Generator; 10: Front muffler; 11: Main muffler on sports exhaust system; 12: Multi-link rear suspension; 13: PASM damper; 14: Oil filler pipe; 15: Air filter; 16: Composite brake discs; 17: Engine mount

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1

1

13

161312

8

9

76

514

10

17

15

11

10

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from the world of motorsport has a verydistinctive appearance and also allowsthe tires to be changed more quickly.This is a major benefit for customerswho want to use their new 911 GT3 onthe racetrack. In addition, the new sys-tem, which is fully enclosed, is ideal foreveryday use because it is protectedmore effectively from dirt than an open5-hole fitting.

The second decimal place – It’s howwe measure our achievements.

The engine of the new 911 GT3 isbased on the 6-cylinder boxer engineof its predecessor. The displacementhas been increased from 3.6 liters to3.8 liters. With a power output per liter

of 84.3 kW or 114.6 bhp, it is one ofthe most powerful sports cars with anaturally aspirated engine. It has a ver-tically split alloy crankcase. The high-strength crankshaft with 8 main bear-ings and the “sandwich” design of theshort engine come originally from the911 GT1. In this case “sandwich” de-sign means that the barrels, cylinderhead and camshaft housing in eachrow of cylinders are individual compo-nents and are bolted to the crankcase.The increase in displacement from3600 cc to 3797 cc was achieved byenlarging the bore from 100 to 102.7mm and enlarging the pistons accord-ingly. The diameter of the piston pinswas increased from 21 to 22 mm inorder to ensure that they were suffi-

ciently strong. Despite this increaseand the larger diameter pistons, de-tailed adjustments to the design al-lowed the weight of the pistons andpins to be kept the same as the previ-ous model. Lightweight titanium con-necting rods are part of the high enginespeed design of the 911 GT3. The ma-terial used ensures that the connectingrods have sufficient strength at high en-gine speeds (8500 rpm) and allow forthe necessary reserves of speed re-quired by racing engines (more than9500 rpm). The titanium connectingrods are around 150 grams or 26 per-cent lighter than equivalent steel com-ponents. The lubrication system con-sists of a traditional dry sump with ex-ternal oil reservoir. The oil pump is

4

Engine Porsche 911 GT3

driven by the crankshaft via intermediateand connecting shafts. The pump con-sists of three segments, one of which isresponsible for the high pressure oilsupply to the engine. It pumps the en-gine oil out of the separate oil reservoirvia an oil/water heat exchanger to theoil filter where it is fed into the engineoil circuit. The other two pump seg-ments pump the oil out of the crank -case and back into the separate oilreservoir. The four oil pumps which ex-tract the oil from the cylinder headshave been moved. They are now in acentral position in a separate moduletogether with the water pump at theback of the engine. Other changes in-clude new oil lines between the cylin-der heads and the oil extraction pumps.In total the new 911 GT3 has seven oilpumps. The cylinder heads are madefrom a highly heat resistant lightweightalloy and have additional cooling forthe exhaust valve seats.

Dynamic engine mounts

For the first time dynamic engine mountshave been fitted to the new 911 GT3in order to improve the driving perform-ance. These dynamic engine mountsautomatically keep noticeable oscilla-tion and vibration of the entire drive-

train, in particular the engine, to a mini-mum by means of an electronically con -trolled mount system. This is the resultof a change in the hardness of the mountcaused by a magnetizable (magneto -rheolo gical) liquid and an electrically gen -erated magnetic field. The inertia of theengine, for example when steering intoa corner or driving through a chicane,exerts a delayed force on the body andtherefore on the chassis. Hard enginemounts significantly reduce this effectand result in more stable and accuratehandling. In racing cars the engine isbolted to the body to keep this effectto a minimum. However, the disadvan-tages of this solution are more notice-able engine vibration and a car which isless suitable for everyday use. Softermounts filter the engine vibrations. Thedynamic engine mounts also reducethe vertical oscillation of the engineduring acceleration under full load.The result is smoother delivery of alarger amount of power to the rearaxle with increased traction and betteracceleration.

The new PADM (Porsche Active Drivetrain Mount) dynamic engine mount

The PASM actively controls the damping forces

1 2 3 4

1: Rebound in ‘Normal mode’ – damper piston and bypassvalve; 2: Rebound in ‘Sport’ mode – damper piston only; 3: Compression in ‘Normal’ mode damper piston and bypassvalve; 4: Compression in ‘Sport’ mode – damper piston only

13

Drivetrain Wheel development

14

As well as looking good, wheels have anumber of other functions. They formthe direct link between the surface onwhich the vehicle is travelling and thepower produced by the drivetrain. In ad-dition to influencing the overall appear-ance of the vehicle, the wheels alsohave an impact on its structural durabil-ity, comfort, dynamic performance andother safety features. For this reason,the engineers in Weissach are workingevery day on making wheels even lighter,more robust and more attractive. Youcould say that they are reinventing thewheel on a daily basis.

Complex development process

At Porsche the process of creating awheel consists of three complex areas.The first of these is the definition anddesign phase, during which the engi-neers and designers specify their re-quirements for the wheel. Next comesthe implementation phase when thestrength of the wheel is determined andcalculated and the drawings are created.The manufacturing process only beginsafter subsequent agreement with thesuppliers. Porsche developers chooseone of three production processes forthe manufacture of the wheels: low-pressure casting, flow forming andforging. Low-pressure casting is usedprimarily for smaller wheels. In the so-called chill casting process, the liquidaluminum is fed at high pressure into a

structure, together with corrosion andcoating adhesion. During rotary bend-ing, impact and radial runout tests andother tests on the Porsche biaxial wheeltest stand (ZWARP), the wheels mustshow that they meet all the relevant re-quirements. Only when the wheels havesuccessfully passed all these tests arethey approved for use on a Porsche.

Staying on track

There is a long tradition of wheel de-velopment at Porsche. In 1962, whenPorsche began developing the 911 range,the engineers were looking for a very spe-cial wheel for the new model. They need-ed an alloy wheel with excellent proper-ties and a completely new look. As aresult of their work on development pro -jects for the German army, the Porscheengineers already had experience of al-loy wheels. The track rollers of the tankrunning gear they had developed weremade of forged aluminum. Therefore theydecided to use the experience from thisproject. The 911 was the first car to haveforged alloy wheels – the Fuchs wheelswhich are still popular today. But thatwas not the end of wheel developmentat Porsche, it was only the beginning.Many more high points were to come,as a glance at the history of Porschewheels shows. Because of their lightweight and high levels of stability, onlyalloy wheels are now used at Porsche,made mainly of aluminum.

Reinventing the wheel every day at Porsche

No other self-contained component which requires relatively little development work

makes such a powerful and impressive impact on the appearance and image of a

vehicle as the wheels.

mold and remains there until it solidi-fies. Every cast wheel is X-rayed to en-sure that the microstructure is of the re-quired quality. The result of the processis the cast wheel, which is already clear-ly recognizable and which is then turnedon the lathe, drilled and deburred. Flowforming is a metal forming process inwhich the wheel rim base is rolled outover a mandrel by one or more rollers.The diameter of the wheel and the thick-ness of the material can be changed atthe same time. By rolling the wheel rimbase, the Weissach engineers can re-duce the wall thickness of the rim by upto a millimeter without compromisingits stability. During the forging process,the wheel is created under pressurefrom a solid block of aluminum in sever-al stages. The forging mold determinesthe result of the process. As forging in-volves high pressures and several phas-es of production, it is one of the mostcostly and time-consuming methods ofproducing wheels. The Porsche devel-opers make use of this process whenmanufacturing the Exclusive wheels forthe Porsche 911 turbo. Regardless ofwhich process is used, all of the wheelshave one thing in common. They are allsubjected to strict testing proceduresby the Weissach engineers before theycan be fitted to a Porsche. Each type of wheel must comply with predefinedmaterial, surface and strength specifi-cations. The criteria include tensilestrength, strain, hardness and micro-

Drivetrain Wheel development

15

1899 1942 1966 1967

1979 1983 1985 1988

1991 1993 1995 2003

Porsche tractor type 112/4 “Fuchs rims” of the 911 coupé

Forged aluminum wheels with aluminum Fuchs rims make it easy to identify the sporty 911 S.

910 magnesium wheels

Die-cast magnesium wheels with a central locking device and alloynut.

Porsche 924 Turbo

Vehicles are fitted as standardwith alloy wheels with five wheelstuds.

Carrera die-cast wheels

The 911 Carrera had 15-inch die-cast alloy wheels with a “telephonedial” design.

Porsche 959 Porsche 928 S 4

For the first time a production vehicle was fitted with a tire pressure monitoring system.

Porsche Carrera RS

Cast magnesium 17-inch wheelswere used for the first time.

Porsche 911 Turbo S 3.3

Initially the Turbo S had 18-inch alloy wheels in three parts with bolted rims in the Cup design.

Hollow spokes – 911 Turbo

Hollow spokes were used for thefirst time on aluminum wheels.

Carrera GT

Forged magnesium wheel with a central locking device as stan-dard.

The cast magnesium wheel hadhollow spokes containing sensorswhich indicated to the driver if thetire pressure dropped.

The driving wheels on the tractorare enclosed.

The two front wheels of the Lohner Porsche contain two electric motors.

Lohner Porsche

Insights ASCS

16

Product development using numeric simulation

Thirty years ago the process of devel-oping vehicles was almost exclusively amanual one. Designers produced thefirst sketches on the drawing board andincreasingly detailed models were test-ed repeatedly for stability, handling andmany other criteria. Globalization andthe accompanying competitive pres-sures have resulted in product develop-ment cycles being drastically shortenedover the years. Car manufacturers arefaced with the challenge of reducingcosts, improving product quality andcutting product development times. Inorder to achieve these objectives, the

automotive industry relies increasinglyon virtual development methods. Thegoal is not to replace the current devel-opment process with a completely newand revolutionary digital process, but tochoose the best possible method foreach task.

The Automotive Simulation Center inStuttgart (ASCS), established by theUniversity of Stuttgart, Dr. Ing. h. c. F.Porsche AG and eleven other automo-tive companies and suppliers, brings to-gether the necessary competence inthis area. The research centers and the

high-performance computing center(HLRS) at the University of Stuttgartprovide the ideal conditions for researchinto applied numerical simulation. Thereare relatively few comparable high-per-formance computing centers in Germany.The computing center is managed bythe company hww Betriebs gesellschaftmbH which was founded in 1995. Bycombining competence in IT, engineer-ing and mathematics, the center aimsto reinforce and develop further itsleading position in the field of appliednumerical simulation in the automotiveindustry. This project was initiated by

The Automotive Simulation Center Stuttgart (ASCS) provides the industry with the

ideal conditions for developing and optimizing products using the latest numerical

simulation methods.

Areas of competence of the Automotive Simulation Center Stuttgart

Automotive

� Energy efficiency� Minimizing CO2 emissions� Cutting particulate levels� Noise reduction� Overall vehicle concept� Lightweight structures� Safety (active, passive)

Modeling and simulation

� Rapid modeling� Validation and certification � High performance computing� Virtual world (virtual reality)

Mathematics

� Basic principles� Computer algebra � Numerical analysis� Optimization

Information and communication

� Vehicle electronics� Telematics� Traffic flow optimization� Driver assistance systems

Insights ASCS

17

Christoph Gümbel who is head of thedepartment for development and inno-vation for virtual vehicles at Porsche.He is particularly pleased that it hasbeen possible to involve a large numberof the relevant companies in the projectin just a short time. The ASCS representsa platform for developing innovative sim-ulation methods. These are needed inorder to meet the challenge of develop-ing future generations of vehicles. Eachsimulation pro cess is based on a mathe-matical model in which a huge numberof equations have to be solved numeri-cally at the same time, in order, for ex-ample, to optimize combustion proc -esses. A high level of computing poweris only useful if it can be accessed easilyfrom each engineer’s workplace. This ismade possible by high-speed networksprovided by CNS (CommunikationsnetzeSüdwest) and by high-performance work -stations and a corresponding computerlandscape which are available to thePorsche engineers.

The ASCS is involved in simulation in awide range of automotive-related areas,including the reduction of fuel con-sumption, pollution and noise and thedevelopment of electric and hybrid ve-

Positioning of the Automotive Simulation Center Stuttgart

Environmental sustainability

Com

putin

g po

wer

very

hig

hm

ediu

m

very highmedium

very

low

very low

Automotive Simulation CenterStuttgart

hicles. The development of fuel-efficientvehicles and the further reduction ofCO2 emissions represent a major chal-lenge for Porsche engineers. In addi-tion, numerical simulations can be usedto test at an early stage of developmentwhether the chosen design meets all theaerodynamic requirements or whetherall the necessary components will fit inthe engine compartment. Real proto-types are now used much less often forthis type of purpose.

Time-consuming computing processesare needed for these simulations. How-

ever, the performance of the computersand the numerical software place re-strictions on what can be achieved. Thisis why the ASCS is focusing increasinglyon cooperation with the scientific world,as Professor Erich Schelkle, managingdirector of the ASCS, explains: “For ex-ample, the University of Stuttgart canprovide expertise in a number of differ-ent areas. In addition to the HLRS, whichhas the latest cluster systems with sev-eral thousand CPUs and very high levelsof per formance, the new Cluster of Ex-cellence 'Simulation Technology' (SRCSimTech) has now also been included.”

Complete vehicle Porsche Panamera

18

The Porsche Panamera sets new standards

With a light touch

The body of the Panamera is the per-fect combination of a lightweight sports -car-style design, high levels of ride com-fort, a spacious interior and efficientaerodynamics. A large underbody panel,which for the first time covers the rearmuffler, and other sophisticated aerody-namic details give the Panamera a verylow drag coefficient (cw) of 0.29. Theunderbody weighs 40 percent less than

conventional systems and helps to re-duce the lift on the ve hicle significantly.On the Panamera Turbo an adaptive

rear wing, which is perfectly integratedinto the bodywork, helps to provide thenecessary downforce at high speeds.The wing has adjustable sides whichhelp to optimize the vehicle’s aerody-namics and performance by adjustingthe angles and surface geometry tosuit the vehicle’s situation.

An intelligent mix of materials has beenused in the Panamera. The componentsresponsible for the safety and stability ofThe adjustable rear spoiler on the Turbo

During the development of the Panamera the engineers at Porsche had to draw on their

entire range of skills. In this article you can gain an insight into the development process for

the Panamera and find out more about the engineering highlights of the fourth dimension at

Porsche. In one thousand hours of highly detailed work the engineers analyzed solutions and

developed alternatives only to reject them again, until they were fully satisfied with the results.


19

the Panamera are made of high-strengthalloy steel (16 percent of the materialmix), while for add-on parts, such as theengine hood and components at the rearof the vehicle, lightweight metals, includ-ing magnesium and aluminum (22 per-cent), are used. The lightweight doors,for example, have a supporting structuremade of laser-machined die-cast alu-minum, an aluminum outer skin and awindow frame made of thin die-castmagnesium. Other materials includedeep-drawing steels (20 percent), higherstrength steels (25 percent) and multi-phase steels (11 percent). In addition,stainless steel and plastic are used. Theintelligent choice of lightweight materialskeeps the weight of the Panamera S, forexample, to as little as 1770 kilograms.

The weight-saving principle was also ap-plied to the interior of the Panamera. Therear seats of the Gran Turismo set newstandards of comfort and adjustability inthe premium class. The molded individ-ual seats, which have special headrestsand an aluminum frame, offer the high-est levels of comfort, even in the rear.The seats are also available on requestwith versatile electrical adjustment andclimate control options. Another striking

feature of the Panamera is its highlyfunctional and variable luggage compart-ment. The split, folding rear seat backswith additional luggage compartmentoverflow area allow for a luggage com-partment with a volume of up to 1263liters and a floor on one level. One othernew feature is the sun sensor in thewindshield. The intensity of the sunlightand the angle of the rays are measuredover an area of four square meters andthe information sent to the climate con-trol system.

The fastest concert hall in the world

It is not only the Burmester high-end sur-round sound system, used for the firsttime in a production model, which en-sures a premium audio experience in thePanamera. By carefully coordinating thesound from the exhaust system, the airintake, the engine and the aero-acoustics,

the developers have succeeded in trans-forming the sound produced by thePanamera into a characteristic and har-monious overall pattern. For example,the aero-acoustics were analyzed using a clay model at a very early stage of de-velopment and were then optimized byapplying a range of different selectivemeasures. The results are impressive:wind noise is kept to a minimum in theinterior of the vehicle in line with whatis expected of a premium class model.However, the typical Porsche sound,which conveys a sense of power anddynamics, can still be heard under ac-celeration. The wide spectrum of soundsproduced by the Panamera ranges fromdiscreet and unobtrusive noise whilethe vehicle is cruising to a sound whichevokes a strong emotional responsewhen the Panamera is driven in a moresporty style. The selective use of bothnew and tried-and-tested technologies

Deep drawing steels

High-strength alloy steel

Magnesium

Multiphase steels

Higher-strength steels

Aluminum

Axle with adaptive air suspension

Lightweight design with an intelligent mix of materials


20

Electronically controlled all-wheel drive with integrated front differential

tall seventh gear which functions as anoverdrive saves even more fuel. As a re-sult of the optimum gear ratios and un-paralleled, ultra-fast gearshifting withoutany interruption to engine power, it alsooffers exceptional performance. In addi-tion, the PDK is 15 kilograms lighter thanconventional automatic gearboxes.

The Panamera 4S and Turbo come asstandard with PDK and Porsche TractionManagement (PTM). The PTM system inthe Panamera consists of active all-wheeldrive in the form of controlled “hang-on”all-wheel drive, which is integrated intothe housing of the PDK. The electronicallycontrolled multiplate clutch is respon -sible for the fully variable distribution ofthe propulsion force between the perma-nently driven rear axle and the front axle.There is no fixed distribution pattern.This ensures increased agility and dy-namics, improved traction and stability,greater control over the vehicle and in-

creased safety as the vehicle reaches itshandling limits. In addition, this system islighter in weight and uses less fuel thanconventional all-wheel drive systems, be-cause it is particularly compact. It alsooffers improved performance as a resultof its low centre of gravity.

Start/stop saves fuel

One of many engineering highlights inthe Panamera and a first in the pre mi -um class is the start/stop system com-bined with an automatic gearbox, whichcomes as standard in all versions of thePanamera with the PDK. This system au-tomatically switches off the engine whenthe vehicle comes to a stop, for exam-ple at a red light, and starts it again im-mediately when the brake pedal is re-leased. All of this is fully automatic withno need for intervention from the driver.The start/stop process is accompaniedby a new rapid engine starting function,

has allowed the engineers at Weissachto develop intelligent solutions in orderto fulfill apparently contradictory ob-jectives during the development of thePanamera.

Aiming for performance and efficiency

The Panamera is supplied only with en-gines using fuel-efficient direct injection

systems. The resulting reduction in fric-tion in the engines is accompanied bynew features such as the map-controlledcoolant heat management system and areduction in the weight of moving partsand auxiliary components in order to im-prove their efficiency. The Porsche Dop-pelkupplung (PDK) in the Panamera isthe first double-clutch gearbox offeredby Porsche in the premium segment. Itimproves efficiency, provides exception-ally sporty performance and gives a verycomfortable ride. The PDK is significantlymore efficient than a conventional auto-matic gearbox and the addition of the

The Panamera Turbo engine


21

addition, the highly innovative adaptiveair suspension system with additionalair volume on demand which is avail-able as standard on the Panamera Turboand as an optional extra on the othermodels further improves the comfortof the ride. The chassis characteristicscan be changed from the driver’s seatwith the simple press of a button. Otherfeatures of the newly developed light-weight chassis include very high levelsof stiffness, agile handling for activesafety and sensitive steering allowinghigh-precision control.

The driving dynamics and comfort canbe further increased on all modelsus ing the active anti-roll system PDCC(Porsche Dynamic Chassis Control) whichimproves the vehicle’s response to un-even surfaces in a straight line and issupplied in conjunction with a controlledrear axle differential. The PDCC resultsin an eight percent increase in maximumlateral acceleration, high levels of active

safety as a result of its active anti-rollfeatures and improved control of the ve-hicle in particular as it reaches its han-dling limits. The developers in Weissachhave not only succeeded with style inachieving the perfect balance betweencomfort and performance. By reducingfriction they have also been able to cutfuel consumption.

The Sport Plus button of the optionalSports Chrono package enables thedriver to select the uncompromisinghigh-performance set-up of all drivetrainand suspension systems at the press ofa button.

Flexible control center

Porsche has entered a new dimensionwith the Panamera and is working onthe evolution of the model. In future,the Panamera will be available with ahybrid drivetrain and a V6 engine. Youcan find out more in future issues.

which starts the engine very quietly andquickly. The main benefit of this systemis obvious; it improves efficiency. Theautomated start/stop system resultsnot only in a reduction in emissions butalso in a significant drop in fuel con-sumption in particular in urban driving.The improvement in fuel consumption inthe New European Driving Cycle (NEDC)brought about by all the technical solu-tions in the Panamera amounts to an ex-cellent figure of 23 percent. Alongsidethe start/stop system, these solutionsinclude the PDK, improved aerodynam-ics, optimum operating strategies andreduced friction and hydraulic losses.Combined with other selective meas-ures to improve the efficiency of theentire vehicle, such as low rolling-resist-ance tires and reduced residual brakingtorque, this results in a fuel consump-tion figure for the Panamera S with PDKof only 10.8 liters per 100 kilometers inthe NEDC.

Focused on the future

Right at the start of the developmentprocess for the Panamera, it was clearthat the chassis must not be a compro-mise, but instead must offer the perfectcombination of sportiness and comfort.The Porsche developers have providedthe ideal solution for this technically de-manding balancing act. The basic set-upof the Panamera chassis provides theoccupants of the vehicle with high levelsof comfort. However, the chassis can betransformed at the press of a button intoan agile sports chassis, with the help ofthe PASM (Porsche Active SuspensionManagement) active damper system. In

PASM – the active suspension system with additional air volume on demand

Electrics & Electronics Testing

22

To test or not to test – that is beyond question!

Complex electrical networks consist ofdecentralized control units and the accompanying sensors and actuatorswhich ensure that everything functionsperfectly. Faults often occur not just inindividual components or control unitsbut in assemblies with componentsfrom more than one system. As a result,the engineers at Porsche Engineeringnot only carry out conventional compo-nent and function tests, but also testcomponents in these assemblies. Thetest strategies are specially designedand implemented to meet customers’requirements.

Individual control unit tests

The functions and interfaces of the indi-vidual control units can be tested usinga hardware-in-the-loop (HIL) test benchor a domain test environment. In this

case the test systems simulate the in-terfaces to the vehicle and the othersystems. By selectively changing one ormore parameters, the test specimencan be artificially stressed and exposedto faults.

Integration testing in the vehicleassembly

An additional test can be carried outwithin the normal vehicle assembly, bychanging the test conditions to cover allthe control units. The important factorhere is to ensure that all the electricalcomponents are assembled in an envi-ronment as similar as possible to that inthe vehicle. The use of a breadboardwith an original vehicle wiring harnesshas proved particularly successful inthis context. At Porsche Engineeringthis is also referred to as CANmobil

(mobile controller area network). Acomplete vehicle is created from anelectrical perspective, but the individualcomponents are much more easily accessible than they would be inside a normal vehicle body. This makes itmuch easier to manipulate control vari-ables selectively and to connect thesystems to the measurement devices.

Testing the electrical interface on a net-work test system (also called a domaintest environment) is an essential part ofthe design process for new controlunits and is also important for integra-tion testing of carry-over parts (COP)systems in a new vehicle assembly. Thisallows automatic checks to be carriedout of components’ compliance withstandards. In addition, by using stan-dard macros, complex test sequencescan be created which allow control

The proportion of electronic components in modern vehicles is rapidly rising.

Increasingly sophisticated test procedures are needed in order to ensure that all

these components interact with one another without problems.

Sequence of test strategies for modern networked vehicle systems

Approval for controlunits requested

Provision of samples Testing control units Testing assembly

Electronics integration starts

Deadline forsupply of parts

Assemblyprocessstarts

Final check

Assembly tested and control units ordered

Electrics & Electronics Testing

23

units’ responses to the aging process,discharged batteries and cold startingbehavior to be simulated, together withthe simulation of short circuits. Hard-ware-in-the-loop tests are ideally suitedfor ensuring that control functions andalgorithms in new vehicle systems arecorrect right at the start of the develop-ment process. They are therefore an es-sential component of all modern teststrategies. Porsche engineers also useHIL tests to carry out “no-risk simula-tions” which would involve significantsafety risks for the test driver in real-lifesituations. In time-cri tical developmentprocesses where HIL tests cannot beused because deadlines are too tight orwhere the creation of an HIL system nolonger makes sense because of thestage of development already reached,the Porsche Engineering Creator forMeasurement in Auto-Network (PEC-M-

needed to create the test catalog andtherefore a shorter time-to-market, ac-companied by improvements in productquality.

Other tools even allow measurementsin the form of trace files from data bussystems, such as CANs or LINs (localinterconnect networks), to be testedautomatically for common faults or pro-tocols to be evaluated in real-life situa-tions. At Porsche Engineering the phy -sical interface between the individualcontrol units is tested fully automaticallyto ensure that the quality and timing ofthe signal sequence is correct. The initialevaluation has even been completelyautomated.

Test strategy

Porsche Engineering ensures that thetest strategy is incorporated into thecustomer’s development model at anearly stage. Whether the customer us-es V models or a different method, thestrategy is adapted to the schedule,the implementation plan and the depthand sequence of the testing process.As well as automating standard tasks,the test engineer can also combine hisexperience with a detailed analysis ofthe possible effects for each specificproduct.

This networked approach allows for aqualification process which is not onlybased on specified standards and criti-cal values, but also takes into accountthe specific requirements of the mostimportant environment to which a vehi-cle is exposed, in other words, everydayuse on the road.

AN) is used. This system, developed byPorsche Engineering, makes it possibleto carry out automatic function testingof the CAN and its accompanying data-base (CAN matrix) in order to checkphysical variables, such as sensor val-ues and control unit res ponses. Analogmeasurements are compared with CANtelegrams, responses to messages orsignals sent to digital and analog inputsare monitored and the results com-bined with the personal assessmentsmade by the tester.

All the steps in the process are care-fully logged and evaluated and the re-sulting test sequences are comparedwith the function definitions using com-puter systems. In future, standards suchas function definitions in the AUTOSARformat will also be supported. The re-sult is a reduction in the time and effort

Integrating the test strategy into the approval process

Stage 1

SupplierRelease plan Individual test

sample

Stage 2

Proposed installation instructionsApplication

Stage 3

TestingIndividual test release plan

Repeat testOptional

individual test

Stage 6

Assembly andintegration

test

Stage 5

On-receipt testComparison ofrequirements/actual situation

Stage 4

Order(Sample part)

Stage 7

Risk assessment

Stage 8

Approval recommended

Stage 9

ApprovalAcceptance of

installation instructions

Stage 10

Build prototypes

Trials

Engine RS Spyder

24

From inner conviction

The version of the engine in the PorscheRS Spyder which was used in the Ameri-can Le Mans Series (ALMS), among oth-ers, until 2008 is a true masterpiece.The initial versions of the engine, whichis referred to at Porsche as the MR6,clearly indicated the goal of the devel-opers, which was not just to take part inthe Le Mans Prototype class (LMP2),but to lead it. Despite the ambitious na-ture of their goal, the developers weresuccessful in achieving it. The eight cy-

linders of the 3.4 liter engine, whichmake up a 90 degree V8 configuration,when combined with the four overheadcamshafts, the individual throttle valvesand, most recently, direct fuel injection,form a unit in which every component isin perfect harmony.

Increasing performance

The Porsche engineers have succeed-ed in increasing the performance of the

MR6 from 476 bhp (351 kW) to 503 bhp(370 kW) as a result of the introduc-tion of direct fuel injection. The maxi-mum torque has been increased from370 Newton meters (Nm) at 7500revs to 384 Nm at 8500 revs. Takinginto account ALMS regulations, this in-crease in power is even more remark-able, as the regulations require amongother things a restriction on the vol-ume of air available to the air intake.This puts a limit on the possible enginepower. However, the Porsche develop-ers identified areas for improvementand were able to increase the power,while at the same time reducing fuelconsumption. The requirement was toachieve the highest possible level of

The Porsche RS Spyder has a whole succession of victories

behind it. The story of its success is uninterrupted. One de-

cisive factor in all of this is the engine which lies at its heart.

Engine RS Spyder

25

efficiency in combination with maxi-mum endurance.

A glance at the engine components indi-cates the special features which are re-sponsible for the performance of theMR6. A bore of 95 mm, combined witha stroke of 59.90 mm, gives the MR6a displacement of 3399.5 cubic centi -meters (3.4 liters). The noteworthyfeatures of the combustion chamberinclude flat piston crowns, small valveangles of less than 25 degrees in accor-dance with requirements and the spe-cial shape of the chamber itself, whichallows enough space for four valves percylinder. The engine of the RS Spyderuses ACO (Automobile Club de l’Ouest)E10 racing fuel, which consists of tenpercent bioethanol, at a compressionratio of 15:1. In order to keep the weightof the engine as low as possible, light-weight, very tough aluminum was usedto make the engine block and the cylin-der head. The Porsche developers de-cided to dispense with cylinder liners andinstead used a nickel-silicon-carboncoating inside the cylinders to reducefriction. Titanium connecting rods areresponsible for transferring the powerfrom the pistons to the steel crankshaftwhich has five main bearings. Titanium

of 0W-40 is used to lubricate the indi-vidual components of the MR6 engine.The same oil is used in Porsche RSR,Cup and production vehicles. The per-fect symbiosis of all the components,combined with the newly developeddirect fuel injection system, allows the en -gine to reach speeds of up to 11,000revs. During the development processof the RS Spyder engine, extensive usewas made of synergies with volumeproduction and motorsport at Porsche.In particular when simulating internal

is known for its high strength, stiffness,durability and light weight. The para -meters relevant to the operation of theengine, such as injection timing, injec-tion volume and ignition timing, arecontrolled by a sophisticated electronicengine management system. The spe-cially developed combustion procedureallows the engine to run on a very leanpetrol/air mixture during long safety-car phases or in the pits, resulting in asignificant reduction in fuel consump-tion. Exxon Mobil 1 oil with a viscosity

The MR6 engine of the RS Spyder with DFI technology

Engine highlights (2008)

Type Concept

Engine type/Number of cylinders Displacement Performance Torque Air volume restrictor Fuel management Intake system Gas exchange

Lubrication system/Oil supply Lubricant Engine management Exhaust system

Porsche MR6 (2008) endurance racing engine, compact and lightweight, very low center of gravity, integrated into the chassis as a load-bearing component 90 degree V8 3397 cm3

478 bhp or 503 bhp (DFI) at 10,000 revs 370 Nm or 385 Nm (DFI) 1 x 42.9 mm Ø intake manifold fuel injection or direct fuel injection (DFI) with individual throttle valves 4 valves per cylinder, each with double overhead camshafts (DOHC) Dry sump lubrication, oil/water heat exchanger Mobil 1 (0W-40) Electronic engine management High-performance exhaust manifold, silencer in accordance with the regulations

Engine RS Spyder

26

form for top-class prototype racing. Aglance at the previous successes of theRS Spyder indicates how carefully thedevelopers from Weissach have followedthese regulations. The RS Spyder’s seriesof successes in 2006 and 2007 contin-ued uninterrupted in the 2008 season.For the third time in a row, the RS Spyderwon the manufacturer’s, team and dri-

ver’s championships. One particular high-light at the start of the season was a his-toric 18th overall victory at the 12 hoursof Sebring, exactly 20 years after the lastoverall victory.

And as if that wasn’t enough, the PorscheRS Spyder also won the first GreenChallenge of the ALMS in 2008, which

engine flows and the gas exchange, theteams worked closely together on theimportant details. For the process of in-tegrating the motor into the vehicle as awhole, the Porsche developers fromWeissach were able to make use of allthe experience which they had acquiredon other projects. In order to ensure anideal distribution of weight and the sta-bility of the vehicle, the drivetrain of thePorsche RS Spyder was designed as aload-bearing component and was fullyintegrated into the chassis.

Life in the fast lane

The MR6 engine was specially developedfor use in the Porsche RS Spyder in theLMP2 class. Vehicles in this class mustweigh at least 775 kilograms (since2008: 825 kilograms) and the 8-cylindernaturally aspirated engines must havea maximum displacement of 3400 cubiccentimeters. The concept behind theseregulations is to give the teams a plat- The RS Spyder is one of the first racing cars to exercise almost complete domination over the ALMS series

The Porsche RS Spyder: direct injection reduces fuel consumption and improves performance

Engine RS Spyder

27

Michelin Energy Endurance Challengewith the largest margin. In 2009 it wasalso the winner of the Le Mans efficiencychallenge.

Since the MR6 engine was first used,the Porsche RS Spyder has had a con-stant string of successes. The engineersin Weissach have implemented all therestrictive changes in the regulationswith apparent ease, while at the sametime making the engine even more com -petitive.

The RS Spyder took part in the Le Mans24 hours race in the hands of customerteams in 2008 and 2009 and won theLMP2 class on both occasions by a veryconvincing margin.

is awarded to the most efficient sportsprototype. The factors under considera-tion in the Green Challenge included fuelconsumption, environmental friendlinessand average speed. “Direct fuel injec-tion (DFI) has significantly reduced thefuel consumption of our RS Spyder bothat normal racing speeds and in yellowflag phases. Porsche customers whohave chosen one of the new models withDFI engines will ex perience the sameresults in normal driving,” says GreenChallenge winner Sascha Maasen.

The Porsche RS Spyder won all the effi-ciency challenges in the 2008 season,not only in the American Le Mans se-ries, but also in Europe. At the Le Mans24 hours the sport prototype won the

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