Porsche 911 RS clone (1974) & GT3 RS (2007) Review

Rally Porsches: They are separated by a generation but in the right hands these coupes are both formidable rally weapons.

1974 Porsche 911 RS clone & 2007 GT3 RS

TARMAC RALLY RS PORSCHES: OLD and NEW

[Aug 2007] Snaking and swooping through beautiful forest, invariably slippery and often slimy, The Sideling section of the main A3 trunk road from Launceston to Tasmania’s East Coast, is a character-defining section of tarmac rally road.

It has been one of the marquee stages of Targa Tasmania since the event’s inception in 1992 and those whose names appear at the head of the stage times each year are given special reverence in the garage or at the bar that night.

The two fastest naturally-aspirated cars in both the Modern and Classic competitions in this year’s Targa were both Porsche RS models. And despite the passage of 33 years between Rex Broadbent’s 1974 911 Carrera RS 3.0 replica and Jim Richards’ 2007 GT3 RS the margin at the end of the 13.97km stage was just 4.0secs.

Five stages later down the challenging 10.95km Elephant Pass, there was just 2.0secs between their times and over the remaining 32 stages the gaps were similarly close, with the eight-time Targa winners taking only 24secs less to cover the signature 37.48km Cethana stage than the lesser-known Victorian in his more-travelled classic Porsche.

By journey’s end in Hobart, both were standing on the podium – Richards and navigator Barry Oliver as the first two-wheel drive crew home and just missing their ninth Targa victory in Modern competition by 46secs, while Broadbent and navigator Michael Goedheer celebrated their second Classic competition win.

LEAN MACHINES

For Targa 2007 Richard’s weapon of choice was the latest GT3 RS – the lighter, wider and more-focussed version of the 997-series GT3 that arrived in Australia last year. The choice of the two-wheel drive naturally-aspirated RS over the latest 911 Turbo four-wheel drive coupe that also sits in his workshop was a calculated gamble.

In mainly dry conditions, the lighter, more nimble RS would be faster and more tyre-friendly, he calculated. The RS weighs in at 1375kg – 20kg under the GT3 thanks to its carbonfibre adjustable rear wing, plastic engine lid and rear window and carbonfibre rear wheel hub carriers, homologated on the car for GT motorsport.

But even with its factory rollcage fitted, Richards’ RS weighs in even less at 1355kg thanks to freedoms allowed under the Targa Tasmania regulations.

The new RS shares the same 3.6-litre boxer-six engine as the GT3 which delivers 305kW/405Nm. With a revised engine management system and a virtually straight-through exhaust Richards enjoys 10kW or so more.

Add a close-ratio six-speed ‘box, a limited differential, a suite of Porsche’s traction control systems and you have a formidable weapon in anyone’s hands and an expertly guided missile in Richards’.

ROUGH DIAMOND

Rex Broadbent’s 1974 model 911 RS clone is simple and crude by comparison, reflecting not only many generations of Porsche technology and development, but also a hard and chequered existence.

The car started life as a brown, Australian-delivered 2.7-litre 911 – the humblest model in Porsche’s 1974 model line-up, but it was competing in the then-fledgling Australian Porsche Cup series in the late-1980s fitted with tacked-on Turbo wheelarch flares and a 185kW racing engine when Broadbent first saw it.

At that time the former Formula Ford racer was concentrating on mounting his own Carrera Cup campaign with a slant-nosed 911, but not long after selling his car in 1994, he was approached by the brown car’s owner, Bill Hallinan, to develop and race it in the Porsche Cup support race for the 1996 Australian GP.

By then the car had been upgraded to even wider RSR bodywork, painted pale yellow and was powered by a 3.4-litre engine producing around 260kW. But Broadbent made a number of changes, fitting a rollcage, a close-ratio gearbox and trimming its rear bodywork back to a more aerodynamic width. It all paid off when he finished third in the main Porsche race.

While initial offers to buy the car were unsuccessful, he and Hallinan came to an arrangement several years later when Broadbent was looking for a car to run in Targa Tasmania. From the outset, the RS showed promise in the then-rejuvenated Classic competition, but proved unreliable, breaking an engine mount while in the leading bunch in 2000 and ‘lunching’ its differential while leading the following year.

But in 2002 it all came good and Broadbent, with navigator Michael Goedheer broke through to win the category. Then later the same year they entered Classic Adelaide for the first time and won that too, the first of a series of five successive victories.

The following year he was offered a 911 GT3 to run in the Modern category of Targa and he and Goedheer finished third outright, the first two-wheel drive car home.

Then in 2004/05 he was invited to drive and develop the Daytona Coupe, finishing fifth outright in 2004 and fourth in 2005. He was due to drive a new Daytona in this year’s Modern Targa competition, but when the car wasn’t ready, he dusted off the 911 and he and Goedheer ran in Classic, holding off a determined charge by the NSW crew of Bill Pye and Grant Geelan in their 911 Carrera 3.0 to take their second Targa win in the same car.

FAMILY FEUD

Side-by-side the two cars could be from separate companies, rather than stablemates from different eras. Richards’ RS is sleek and sophisticated; the latest and most dramatic road-going interpretation of Porsche’s current 997 theme.

The excitement starts with the jutting front lip spoiler, laced with intake and extraction cooling ducts. Compared with the GT3, the RS is 44mm wider across the hips, add the complex carbonfibre adjustable rear wing and it looks simply fat and fantastic from the rear. Yet it still manages to achieve a Cd of 0.30 compared with the GT3’s 0.29.

Broadbent’s RS is more like a caricature of an early 911. The original narrow bodywork introduced in 1965 bulges fibreglass additions in every direction and the enormous rear wing clearly earns its nickname of ‘whale-tail’.

Inside, the generational difference is even more marked. The GT3 RS is almost luxurious by early Porsche standards, with standard equipment including air-con, ‘fast glass’, in-dash CD/tuner and even cruise control. There’s also a rev counter red-lined at 8400rpm, 350km/h speedometer, Momo steering wheel and carbonfibre Cobra race seats.

Broadbent’s RS is much simpler. The rev counter reads to 8000 with an adjustable rev limit warning light on top of the dash that cuts in at 7500 and twin VDO Minicockpit navigational aids. The rollcage extends through the firewall to pick up front extremities, while there is a reassuringly high hip bar between the doors and the racing bucket seats.

If you’re used to fussy competition cars that are pigs to get off the line or drive in traffic, the GT3 RS is a revelation. Light and progressive, the clutch can be engaged smoothly at low revs and the car’s engine management system delivers smooth, jerk-free power from above 1500rpm in every gear.

But it’s when you plant your foot that the real fun begins. With a power-to-weight ratio of less than 4.5kg/kW, the RS has stunning acceleration. Conservative factory figures quote 0-100km/h in 4.2secs, 0-200km/h in 13.3secs and a top speed of 310km/h. But in Targa trim, Richards’ RS is faster and sounds even better.

The noise is feral as the car crests its torque curve at 5500rpm and rushes to a shrill crescendo as peak power arrives at 7600. True, the exhaust resonance under part-throttle is tiresome around town, but most of the fun in this car is to be had with your head encased in a helmet.

Gear changes are delightful. Short, precise, sharp. Bang, bang, bang – it just doesn’t come any better – while the steering is nicely weighted and extraordinarily communicative without excessive kick-back on bumps.

GT3 RS models are firm in their suspension settings and even with the standard Porsche Active Suspension System set to ‘standard’, corrugated roads and broken bitumen are experienced a lot more than in humbler 911s. To make matters worse, Richards’ RS is set up stiffer and is slightly higher than standard to better ride the dips and bumps of tarmac rallying.

Broadbent’s 911 is even louder at low revs, as you would expect of a large-capacity air-cooled 911 running on carburettors, but its sound is more of a guttural roar than the GT3 RS’s scream as the revs rise.

At the wheel it’s more of a classic experience too. The clutch is progressive enough, but the throttle has a hair trigger action off idle, so it’s tricky at times to match the two for fuss-free starts in traffic or uphill. Once on the move, it’s easy to drive, if you don’t mind the trademark long throw of Porsche’s Type 915 gearbox.

With an all-up weight of less than 1100kg and around 240kW on tap, Broadbent’s RS has similar power-to-weight to Richards’ GT3 RS, so you would expect similar straight-line performance. There was only one way to find out…

CULTURE CLASH

On our test track we lined up the two RS Porsches side by side and from a rolling first gear start, Richards and Broadbent flogged their respective steeds.

Broadbent’s tall first gear compared to the lower and more numerous ratios of the GT3 immediately took Richards to a car-and-a-half lead and there it stayed as both cars ran up to around 180km/h before wind resistance again began to play in the newer car’s favour. But in the real ‘Targa’ world, that’s not really where the difference of 0.3sec/km separates these two cars and their drivers.

While the old RS has racing AP four-spot callipers from a 1980s Group A Commodore up-front and Porsche 928 S4 brakes at the rear, they aren’t in the same league as the new RS’s six-spot front/four-piston rear ABS system with Brake Force Distribution.

Then there’s the rubber. While both wear the latest Dunlop tarmac treads, the largest diameter rims Broadbent can run in Classic are 17inch, whereas Richards has come down from the RS’s standard 19inch rims in favour of 18inch lightweight Simmons wheels to take advantage of a wider range of the latest Dunlop DO3G tyres and compounds.

And then there’s the price. Now sold out, the GT3 RS cost a tad under $300,000 when it went on sale in Australia early this year. Broadbent’s ‘RS’ cost him a fraction of that to purchase and is worth maybe half the GT3 RS’s price on the tarmac rally market. With a performance that would have placed it eighth outright in the Modern competition in this year’s Targa based on overall time lost, it’s the clear bang-for-buck winner.

SPECIFICATIONS