• Categories
    • Car Racing
    • Featured Articles
    • Motor Shows & Car Events
    • History of Cars
    • Automotive Photography
    • Behind the Scenes
    • #MiniSeries
    • Travel
    • Review Books
    • Review Cars
    • Review Products
  • Porsche Only
    • Engine downsizing at Porsche racing
    • PORSCHE 911 RSR – MARCH OF PROGRESS
    • Porsche 919 Hybrid – Technological Advantage
    • Déjà Vu of Porsche 911 2.4 S – Part 2
  • Book Shop
    • AC-Shelby Cobra
    • Ferrari 250 GTO: Owners’ Workshop Manual
    • Ferrari Design: The Definitive Study
    • Jaguar E-type: Portrait of a Design Icon
    • Porsche 956 962: A Photographic History
    • Porsche 911 Carrera RS interactive eBook
    • Porsche 911 Scrapbook: The Air-Cooled Cars
    • Porsche 917: The Complete Photographic History
    • Porsche 924/928/944/968
    • Porsche at Le Mans
    • Porsche: The Carrera Dynasty
  • About
  • Contributors
    • Alisdair Cusick
    • Annie Proffit
    • Elke Smale
    • Glen Smale
    • John Mountney
    • Pim van der Veer
    • Roland Harrison
    • Zoltan Papp
  • Contact

Virtual Motorpix

Blog site for Virtual Motorpix with interesting articles on racing, motor sports and cars

PORSCHE 911 RSR – MARCH OF PROGRESS

February 19, 2016 by: Virtual Motorpix | Leave a Comment

#92 Porsche 911 RSR, Porsche Team Manthey, driven by Patrick Pilet, Frederic Makowiecki, Wolf Henzler, Q1, Le Mans 24hr 2015
Unfortunately the #92 Porsche 911 RSR driven by Patrick Pilet, Frederic Makowiecki and Wolf Henzler retired with a blown engine after just 14 laps of the 2015 Le Mans 24hr

In 2014, its second year as a works racer, the Porsche 911 RSR finished second to Ferrari in the FIA WEC Manufacturers title race in the GTE PRO class. Porsche finished behind Ferrari, but ahead of Aston Martin. The Porsches scored two race victories to Ferrari’s four, but the 911s racked up six second places between the two cars, to Ferrari’s single second place. Although it was Ferrari’s name that appeared on the trophy, the 911s could boast an impressive record of consistency.

#91 Porsche 911 RSR, Porsche Team Manthey (drivers: Christensen, Lietz, Bergmeister) at the 6 Hours of Silverstone 2015
The #91 Porsche 911 RSR of Christensen and Lietz finished second in the GTE PRO class in the 6 Hours of Silverstone 2015

So what did the engineers back at Weissach get up to over the winter of 2014 to make the RSR into a potential winner in 2015? I spoke to works driver Patrick Pilet and to Dr. Frank-Steffen Walliser, head of Porsche Motorsport, about the 2015 racer that became a Championship winner.

Dr. Frank-Steffen Walliser, Head of Porsche Motorsport in his office at the Silverstone Porsche hospitality at the WEC Silverstone 6h, 10-12 April 2015
Dr. Frank-Steffen Walliser, Head of Porsche Motorsport, in his office at the Silverstone Porsche hospitality at the WEC Silverstone 6h, 10-12 April 2015

Front spoiler

One of the key factors in the development of the 2015 RSR was to improve its ‘drivability.’ Dr. Frank-Steffen Walliser said, “So it was more about how the car behaved under braking, under lift-off, and when you got back on the throttle again, everything to do with the drivability. We focussed on what would give the driver the right feedback to make it easier to handle, so he would know where the car is and whether he had over- or understeer.” By comparison, the front spoiler on the 2015 car was similar to the 2014 model, but the later car has a small raised section in the centre of the front spoiler, allowing some air to flow under the vehicle. This small change means that the level of downforce was not influenced as much when the car lifts off when jumping the curbs.

#91 Porsche 911 RSR, Porsche Team Manthey (drivers: Christensen, Lietz, Bergmeister) at the 6 Hours of Silverstone 2015
This photo taken in the pit garage shows the revised front spoiler of the #91 Porsche 911 RSR as raced at the 6 Hours of Silverstone 2015

Drivability

The drivability factor was of paramount importance, as RSR works driver Patrick Pilet explained, “The 2015 car was more driveable, it was less snappy in the fast corners and it was more efficient.” The instability that the drivers sometimes experienced in the past has gone. The car is now more ‘linear’ as Pilet put it, and is therefore easier to drive as it now sits as opposed to dives under braking. Asked where he felt the biggest difference was, Pilet responded, “Especially on the turn-in on the fast corners because, with the new front that we have, the car is less pointy, or sharp, than before. Sometimes in the initial braking phase we could pick up some instability because we had a small aero difference between the front and the rear.”

#92 Porsche 911 RSR, Porsche Team Manthey (drivers: Makowiecki, Pilet, Henzler) at the 6 Hours of Silverstone 2015
Here the #92 Porsche 911 RSR of Makowiecki, Pilet, Henzler rounds the Luffield complex during the 6 Hours of Silverstone 2015

Body and Aero

The Endurance Committee of the ACO has the absolute right to modify the Balance of Performance (BoP) between GTE cars through adjusting the weight, engine performance or aerodynamics. With this backdrop, the manufacturers and teams must prepare their cars within the guidelines laid down by the regulations. “The rear wing is exactly the same because it is a homologated part, so you cannot change it. There were only slight evolutions possible, but the rear wing was not affected,” Walliser pointed out.

The 2015 RSR body is still the same steel/aluminium hybrid design which uses the 911 Carrera 4 (991) as the base body, as this was the widest body available in the range at the time the race car was homologated. The regulations for GTE PRO cars state that, “The period of restriction will begin for 2013 models for LM GTE-PRO cars. It will be the same for every car.” This set of rules effectively freezes any major changes, which means that this current 911 RSR had to remain the same for the 2013-2014-2015 seasons. Walliser confirms this, “The new three-year homologation period in GTE starts in 2016, and runs to 2018.”

#91 Porsche 911 RSR, Porsche Team Manthey, Jorg Bergmeister, Michael Christensen, Richard Lietz, Le Mans 24H 2015
The #91 works Porsche 911 RSR driven by Jorg Bergmeister, Michael Christensen and Richard Lietz is readied for the 2015 Le Mans 24H

Chassis and weight distribution

Over the winter the Porsche engineers made some small detail changes to the kinematic points on the front axle, as Walliser explains, “They were able to make some slight adjustments, but this had to be done within the rules of the homologated car, so we could only make small adjustments.” It was through some of these small adjustments, which led to the improved handling of the car. Asked if they were able to improve the car’s weight distribution in any way, he responded, “For sure it is always the aim to be able to adjust this weight distribution, but you cannot make tremendous changes.” The regulated minimum weight for the 911 RSR is 1245kg.

#92 Porsche 911 RSR, Porsche Team Manthey GTE Pro, drivers: Wolf Henzler, Frederic Makowieki, Patrick Pilet at Le Mans 24H, 2015
The #91 Porsche 911 RSR passes the pits during the 2015 Le Mans 24H

Engine

The 911 RSR is powered by the same 4-litre aluminium boxer engine as before. It has a bore of 102.7mm and stroke of 80.4mm giving a capacity of 3996cc, and develops 470hp (345kW) when fitted with a pair of 29.3mm restrictors in accordance with the BoP criteria. The engine operates with 4-valve technology, is water-cooled, has dry sump lubrication and multi-point fuel injection.

It is on this last point, the fuel injection system, that the racing Porsche differs from the road-going model. EFI direct injection was used on the 997 back in 2008, so the technology was available but Porsche have previously said that they won’t develop it for racing until they are satisfied that the rules are stable. Walliser pointed out that, “At the moment this car is homologated with the multipoint injection and not direct injection.” However, the privateer teams have been calling for direct injection, not only because of the increase in power it brings, but for the improved fuel consumption it delivers. When prompted on the question of direct injection for the 2016/2017/2018 seasons, Walliser responded, “We will see. It is not finally decided, it depends a lot on circumstances.”

#91 Porsche 911 RSR, Porsche Team Manthey, Jörg Bergmeister getting into the car at Le Mans 24H, 2015
Jörg Bergmeister prepares to board the #91 Porsche 911 RSR during a pit stop at the 2015 Le Mans 24H

From the driver’s point of view, Patrick Pilet said this, “We have a really good engine, but we have the smallest engine of the field, a 4-litre unit without turbo. It develops a lot of horsepower if you take into account the air restrictor size and the fuel capacity that we have, so I think the engine is really optimised. Beyond that, it’s all about durability, and to be sure that the engine has no problems for the long 24-hour races.”

Wheels, brakes and suspension

Keeping the 911 RSR on the track are four Michelin racing tyres mounted on BBS alloys. The front 12.5J x 18 wheels are shod with 30/68-18 Michelin rubber, while the rear 14J x 18 wheels are fitted with 31/71-18 tyres. The Brembo brake system comprises 380mm steel discs with six-piston monobloc fixed brake calipers up front and 355mm steel discs with four-piston units, internally-vented, at the rear. The suspension is a fully-adjustable double-wishbone suspension setup at the front with 4-way gas pressure shocks, double coil springs (main and helper) and adjustable blade-type anti-roll bar. At the rear is a multi-link axle, 4-way adjustable shock absorbers, double coil springs (main and helper) and adjustable blade-type anti-roll bar.

#92 Porsche 911 RSR, Porsche Team Manthey, driven by Patrick Pilet, Frederic Makowiecki, Wolf Henzler, Q1, Le Mans 24hr 2015
The #92 Porsche 911 RSR of Patrick Pilet, Frederic Makowiecki and Wolf Henzler negotiates the Ford Chicane at the start of the pit straight during Q1 of the 2015 Le Mans 24hr

Refuelling

Single point refuelling was introduced in 2015 on the 911 RSR, which greatly contributes to safety in the pit lane. The refuelling system utilises one hose for both filling and venting, leaving only one refueller to work on the car. The refuelling hose consists of a two part concentric tube, so when refuelling commences, the fuel flows down the outer tube and air is forced back up the inner tube. “We can take the second guy, who is standing with his back to the pit lane, out of the process and that was a safety issue,” justified Walliser.

#91 Porsche 911 RSR, Porsche Team Manthey, driven by: Lietz, Christensen, Bergmeister, at Silverstone 6h, 2015
Refuelling of the 911 RSR was made a lot easier and quicker in 2015 with the introduction of the new single point system. Here the #91 Porsche Lietz, Christensen and Bergmeister pits during practice for the Silverstone 6h 2015

Drivers

For the WEC 2015 season opener at Silverstone on 12 April, the drivers were: #91 – Richard Lietz/Michael Christensen, and #92 – Patrick Pilet/Fred Makowiecki. Between these four drivers they have a total of 21 years of combined service as Porsche works drivers, and while Lietz and Pilet claim the bulk of those years, Fred ‘Mako’ has an impressive record in GT racing that stretches back several years. At 24 years of age, Christensen is the youngest and has spent the least amount of time in a Porsche but if you think he is a lightweight, you would be mistaken, as he has come up through the ranks of the Porsche Junior Driver and Porsche Supercup series.

Frederic Makowiecki, Porsche #92 driver, Le Mans 24H, 2015
Frederic Makowiecki, Porsche RSR #92 driver, relaxes during a media session at the 2015 Le Mans 24H

 

#91 Porsche 911 RSR, Michael Christensen is awaiting his car at Le Mans 24H 2015
#91 Porsche 911 RSR driver, Michael Christensen, awaits his stint behind the wheel during the 2015 Le Mans 24H

At Silverstone the lead 911 RSR was almost 7/10ths of a second off the pace of the Aston Martins who had locked out the top three positions on the grid. When asked about the performance gap, Patrick Pilet responded, “Even with the BoP, we know they still have a big power advantage, and especially here you need a lot of torque, and they have lots, but we will see what the pace is during the race. Anyway, we will never give up. We will push harder from the first stint until the last lap, and we will see where we are at the end. But for sure they are strong.”

Jörg Bergmeister awaiting the #91 Porsche 911 RSR in the pits at Le Mans 24H, 2015
Jörg Bergmeister awaiting the #91 Porsche 911 RSR in the pits at Le Mans 24H, 2015

Although Porsche will not be fielding a 911 RSR entry for the whole WEC season in 2016, they will be supporting the #77 Dempsey-Proton Racing 2016 car in the GTE PRO class in all nine races, with Richard Lietz at the wheel. In the GTE AM class, there will be three Porsches in action for the whole WEC season. Round three of the WEC at Le Mans will see the #77 car joined in the GTE PRO class by the usual #91 and #92 works cars with drivers Patrick Pilet and Fred Mako respectively. The GTE PRO class is going to be fiercely contested with fourteen cars this year, what with the inclusion of a squadron of four Ford GTs. Fourteen cars will also be in action in the GTE AM class with four 911 RSRs entered, including one each from the KCMG, Gulf Racing, Abu Dhabi-Proton Racing and Proton Racing teams. Although ninth on the reserve list, another Porsche 911 GTE AM is waiting in the wings should others withdraw.

One thing is for sure, while Porsche wait for their new 911 racer to be ready for 2017, they will be mighty busy in 2016 with such a full field of private and works cars racing throughout the season. And that means that the spectator is going to be in for a feast of action…so take your seats, buckle up and wait for the starter’s orders!!

Written by: Glen Smale

Save article as PDF
Share this:

Categories: Automotive Photography, Car Racing, Featured Articles, Porsche Only Tags: Bergmeister, Le Mans 24H, Makowiecki, Pilet, Porsche, Silverstone, Walliser

Leave a Reply Cancel reply

Top quality commentary and photography on cars, motoring and motorsport across the ages.

Advertisement

Connect with us

  • E-mail
  • Facebook
  • Pinterest
  • Twitter

E-mail Subscription

Please complete the form below if you would like to receive e-mail updates of new posts from Virtual Motorpix Blog.

Recent Articles

  • Toyota Gazoo Racing – 2017 WEC Plans
  • FCA (Fiat Chrysler Alfa) Driving Event Cardiff
  • Fiat 124 Sport Spider
  • Fiat 500
  • Jaguar E-type Restoration – Part 2
  • Cobra-Ferrari Wars 1963-1965
All Tags ››

Archives

Our other websites

Join us on Facebook

Please share our website

Follow us on Twitter

Tweets by Virtual Motorpix Blog

Contact us

We welcome your questions, comments and feedback. Please click here to contact us.

Connect with us

  • E-mail
  • Facebook
  • Pinterest
  • Twitter

Copyright © 2023 Virtual Motorpix. All Rights Reserved.

 

Loading Comments...