RSR Restoration

[550Spyder]

I know a man who knows a man.....

This man is a pretty private guy. He isn't seeking endorsements and knows there will be as many haters as fans. He isn't seeking to turn this into a referendum on the project, or to open up a long chat forum so don't be offended by the silence as absolutely no harm or offence meant.

....a simple record of one mans build...

The benchmark. Start with the end in mind.....

[550Spyder]

A quick history lesson...

By early 1970 Porsche wasn't in great shape financially. While the 917 project was crushing all before it in sports cars and (eventually) CanAm the cost was crippling Porsche. A decision was made to base future generations of race cars on the 911 road car.

M491: THE Carrera RSR OF 1973

To be eligible for Group 4 & 5 (GT) sports cars with the 911, Porsche would be required to homologate 500 cars. The basis for its new competition car the 911 Carrera 2.7 RS of 1973 proved such a success 1580* were built, mainly in Touring (M472) trim and Sport (M471) guise.

Of these, 55 were further converted at the factory to Racing specification, with the build code M491 and the model name Carrera 2.8 RSR.

The Carrera 2.8 RSR was an evolution of the stock Carrera RS. Increased engine capacity (from 2687CC to 2806CC) came with using 92mm diameter pistons (instead of 90mm) and in race tune - with race camshafts, twin spark plugs per cylinder, and a compression ratio of 10.3:1 (against 8.5:1) - the power output was 300bhp instead of the 210bhp of the 2.7 RS. Porsche's 915 transmission was used, with a limited-slip differential as standard.

The RSR retained the lightweight steel, non-stressed, body panels and thin glass of the M471 Sport, along with a lightweight interior, steel wheel arch extensions were fitted to accommodate an increase in track of some 30mm. All-up weight was 917kg.

Although the RSR retained the torsion-bar suspension of the RS, this received assistance from coil 'helper' springs around the front struts and the rear shock absorbers. Harder suspension bushes were fitted, and 9in front and 11in wide rear wheels enclosed modified (ventilated and drilled) versions of the brakes fitted to the short-distance 917 sports racing car.

Visually, apart from the wider track, the RSR could be distinguished from the RS by its deep glass-fibre front bumper, which contained a centrally-placed oil radiator. The ducktail rear spoiler of the RS was retained.

Much of the motorsport participation of the RSR was left to factory-endorsed private teams, Peter Gregg and Hurley Haywood marking the first major success for the 2.8 RSR with victory in the 1973 Daytona 24 Hours. In Europe, Martini and Kremer cars driven by the likes of Gijs van Lennep and John Fitzpatrick were consistent winners, with van Lennep and Herbert Muller winning the Targa Florio and taking fourth overall at Le Mans.

The 1973 Carrera marked a number of firsts for the 911:

First time a 911 had been called a 'Carrera' (earlier 356's had been named Carreras)

First time a 911 was fitted with serious aerodynamics (front spoiler, rear ducktail)

First 911 'wide body' (housing 9&11 inch rims at a time when 6 " was considered exotic)

First 911 with 300 hp (early 911 racers were largely street based cars with low - mid 200hp motors)

After a decade of having sand kicked in its face, in 1973 Porsche finally had a 911 capable of taking on and beating Ferrari, Alfa, Lancia, Matra and Lola in the World Championship of Makes.

[550Spyder]

The Conundrum

Original 1973 Carrera RS sell for AUD $1m, original Carrera RSR sell for AUD$2m......chopper, theres no cash here, here no cash

The Solution

Restore a clean rust free g series 911 as a period correct 1973 Carrera RSR in terms of appearance, power and performance without having to sell the house to live in the car or becoming a friendless hermit.

The Donor:

Low km, Australian delivered, matching numbers, pre cat, manual, RHD, rust free

The Build Spec

Nut & bolt rotisserie restoration, repasivation of metal parts

Bare metal body prep, resin primed (30 day cure), period correct colour (1973 option colour: signal orange)

Correct RSR pressed steel flares (Historika UK)

Correct ducktail, spoilers, steel long bonnet configuration

RSR period correct gauges, waffle dash, momo prototipo, RS door cards, lakewells & leather trim

Period correct leather/houndstooth seats

Braced and pinned 1/2 cage

Polished headlight & window surrounds, handles and correct windscreen washers

Fuchs 15 inch in 9 & 11's

Period correct 915 rebuilt box

Four pot brakes, full bilsteins, braided lines, front brace

Retain 100% steel panels, no glass except ducktail & spoiler

The compromises:

LHD originality vs RHD galvanisation & known accident free history

Cutting a clean car

[550Spyder]

Original pressed metal flares taken from original RSR moulds imported from Horistorika UK. Different to turbo flares. Sunroof removed and replaced with solid roof blank.

Long bonnet conversion with correct indicators and locking mechanism

Engine, glass, electrics, everything out. Body hand rubbed & resin primed, 30 day cure time.

Full rotisserie treatment, strip down and preparation. Every nut & bolt stripped and re pasivated.

[550Spyder]

In 1973 Porsche offered two standard orange colours (018 Tangerine, 114 Signal Yellow) as well as two orange options (019 Gulf Orange, 116 Signal Orange).

Gold neck chains came standard.

Shell finished in 1973 spec Signal Orange.

Thanks to some good advice from Quozl, on trail of 15" Fuchs with period Michelin TB15s. Another compromise avoided. Builder is doing a brilliant job.

[550Spyder]

Porsche completed conversion order M491 to 55 Carrera RS lightweight shelled road cars to bring them up to full 2.8 litre RSR spec making the 1973 Porsche Carrera RSR one of the most exclusive Porsche's ever. Of the 55 genuine factory cars, approximately 12 were factory race cars with the remaining 43 sold to privateers. As the conversion was an option, none of the build numbers were sequential so some controversy exists as to exact final build numbers for both Factory and Privateer cars.

With original Carrera RSRs selling for $2m+, province and originality are a fairly fluid topic for a car that was a homologated race car.

What is originality? When is original not original?

Fiscal pressure: in 1973 Porsche was far from the financial powerhouse it, Audi and VW constitute today. In 1973 money was very tight for racing programmes and Porsche was not in a position to build race cars willy nilly. While the official RSR was a 1973 RS that underwent the Option M491 upgrade, a number of the Factory RSR race cars were in fact existing factory 72 race cars simply updated. The give away being the external oil filler in the right rear quarter panel (a 1972 only feature).

Cross border transport: the cars competed in an era of customs carnets and largely road transport. The carnets were the official import / export documentation and referenced the build plate. The practicalities of fortnightly races, accident damage, road transport and limited mobile panel beating capability created a situation where it was simply easier to swap build plates between cars to ensure that an undamaged car could be matched up with the carnet documentation at the border so the team could drive straight through to the next race.

Accident damage: accident damage at races necessitated a degree of factory 'rebirthing'. At the 1973 Targa Florio in Sicily the factory Martini team destroyed two cars in practice accidents. They had to cobble together one repair and then re-birth the press car by transplanting a race engine / box for the race (securing a top 10 finish in the re birthed press car).

Prototype development: while many Carrera RSRs were homologated to run in Group 4 of the World Championship of Makes / endurance racing, many cars ran in the prototype class. Teams were literally developing the cars at the races on the fly with new specification and improvements. While the Factory Martini cars ran with a standard ducktail at the start of practice for the Targa Florio, for qualifying and the race two cars ran with hastily built extensions made in the pits with tin snips and masking tape. By the next meeting, the prototype cars ran with fully wraparound fibreglass 'Mary Queen of Scots' spoilers. Over the 1973 racing year the engine size grew from 2.8 to 3.0, brake sizes grew, wheel sizes grew with some cars even receiving a rear end grafting from the 917 race car.

URL=http://s12.photobucket.com/user/RSR-Backdate/media/image.jpg1_zpslhjfok7k.jpg.html]

Hastily fitted spoiler extensions fitted during the running of the '73 Targa.

Factory misrepresentation: from 1974-2013 the Porsche Museum displayed a car as the 1973 Targa Florio 'winning car' (chassis 588). Following years of questioning from Porsche enthusiasts the Museum quietly withdrew the car from display and restored it to its correct identity and period livery as the third place getting car (chassis 020), itself an important historical vehicle.

A replica will always be a replica but at least you know what you have.

If you were in the fortunate position to be putting down $2m on a genuine Carrera RSR, you would want to be able to satisfy yourself of provenance and originality.

[550Spyder]

10 'tells' of a M491 execution order (i.e. 1973 Carrera RSR).

At a time when the 'base' donor Carrera RS was USD$ 14,000 and a legend in its own right, the M491 conversion order to upgrade to the full house Carrera RSR was an additional USD $22,500. Big bucks at the time but considering privateer Carerra RSRs won at Sebring 12 hour in 1973 and originals now sell for USD$2m it wasn't all bad news on the value stakes.

Deep beneath the skin the RSR upgrade brought some serious firepower in the form of long range fuel tank, LSD, coil over shocks and the 2.7 litre 210hp RS tickled to 2.8 litre 280hp RSR spec with twin plug heads (and by late 1973 in 3.0 litre form with 300hp).

A nut and bolt FIA accurate recreation is beyond the means of most mere mortals. With only 55 originals produced there are not a lot of genuine parts in stock at Repco. That said, there are 'Ten Tells' any good backdate / recreation should aspire to. They reflect the unique RS/RSR signatures and many Porsche 911 'firsts' that the Carrera RSR established in 1973.

External:

1 Ducktail spoiler

2 Perid correct front & rear RSR wide body chin spoilers with oil cooler

3 Fifteen inch Fuchs in 9 & 11 inch widths

4 Period correct RSR flares

5 Period correct colour, polished alloy trim & correct Carrera stickering

Internal:

6 Correct period VDO gauges with 10,000rpm tacho

7 Correct RS door cards, pull straps and manual wind windows

8 Momo Prototipo wheel

9 Four pot brakes & period correct 915 box

10 Period correct seats & waffle cone/aluminium strip dash runner

Hopefully the end result is as close as most mare mortals can get to a Privateer entry into the 1973 World Championship of Makes Endurance Series. Here privateers took on the big factory teams from Ferrari, Alfa, Matra,Lola and Lancia at Le Mans, Targa Florio, Daytona 24 hr and Spa. A light weight, high mechanical grip, high revving Billie cart unhindered by a world of power steering, air conditioning, power windows, traction and braking aids.

[550Spyder]

Saved for completed post

[550Spyder]

Saved for summary post

[550Spyder]

Saved for RSR History post

[550Spyder]

Saved for spare

[Kerry]

 

Giddy-up!

[turboT]

Nice

[turboT]

Horistorika UK

Just tried googling them. There is a name for this I think, but got zero results. Is the name right or I they that exclusive that Google hasn't heard about them?

[turboT]

Ah - historika

[KGB]

[LeeM]

Historika build some exceptional period correct 911 race cars

[andrew911]

I saw the car on Monday ....   looks great and I like the colour 

[JV911]

[Airhead]

Looks like the rear under body firewall wont be painted?