RUF CTR Yellowbird

RUF’s CTR ‘Yellowbird’ was a sensation when Jesse Crosse travelled to the company’s Pfaffenhausen home to drive it to the max. Thirty-six years later, and with the aid of a new interview with Alois Ruf, he tells the tale with the help of the original images.

Even by today’s standards, 211mph is a big number. Most Porsche enthusiasts will recognise it as the speed which earned Ruf Automobile’s CTR Yellowbird the title of ‘fastest production car in the world’ in April 1987 during Road & Track’s competition to find just that. Then, in a test with the German magazine Auto Motor und Sport at the Nardò Ring the following year, it went even faster and reached a staggering 213mph. That’s impressive, phenomenal even, but even those top speeds don’t convey the sensation of an all-out assault on the mind and body the CTR gives from the driving seat.
 
Company founder Alois Ruf had taken the family garage business over on his father’s death in 1974, began by tuning cars and built the first complete Ruf 911 – a 930 Turbo – in 1975. One successful project led to another and, in 1981, the company was awarded manufacturer status by the German Federal Transport Authority, the Kraftfahrt-Bundesamt (KBA). When I caught up with Ruf recently for the first time since 1989, he explained how that remarkable change of status came about. “It was requested by Porsche that it should be this way and we are a completely separate entity,” he explained. “In that way, there would be no liability issues.”
 
Ruf Automobile gained the unique accolade of being the only company to be supplied with body-in-white shells from the Porsche factory as a basis for its own new cars. But, when the 928 was launched in 1978, there were rumours that Porsche would be discontinuing the 911 and the company’s fortunes really began to change. Customers started asking Ruf if he would be able to build them 911s from parts after factory production had ceased, and so the die was cast.
 
THE SAME BUT DIFFERENT

Thirty-six years ago, I set off to the airport on a trip to Germany to drive a 911. That wasn’t so unusual for a motoring hack in the 1980s, except this 911 was not manufactured by Porsche, but by Ruf Automobile. I would be driving one of 29 production examples of the CTR Yellowbird. It was identical to the record-breaking prototype in every respect, except for the Naca ducts behind the rear wheel arches which had been replaced by the familiar smooth bodywork of a Carrera.
 
“We thought the openings would work in our favour, but they did not. We learned that later,” Ruf chuckled. “We were still the fastest car, though.” Would it have been faster without the Naca ducts? “I doubt it. We had reached the cut-off speed of the engine in fifth gear and overcome the ‘rubber wall’ of air resistance, but the car wouldn’t run faster. We would have needed a taller gear to find out if the ducts would increase the top speed.”
 
Ruf’s headquarters are in the small town of Pfaffenhausen, about an hour and a half’s drive to the west of Munich. The neat premises looked much like any other well-presented town garage and a far cry from the huge industrial setting of most major manufacturers. Met by Ruf himself, we chatted about details for some time and walked around a sister car that was in the process of being built before strapping into the yellow beast and going for a drive.


 
SEIZE THE FIRE

Based as it was on a 3.2 Carrera rather than the 930 Turbo, it felt familiar but unfamiliar: a kind of mash-up of racing car and production road car, the trimmed interior contrasting with deep bucket seats, bright red Sabelt competition full-harness seat belts and a full roll cage. The three-spoke steering wheel with a Ruf logo at its centre was bespoke but, although it didn’t resonate at the time, the most unusual feature was the gear knob embossed not with the four-speed ‘H’-pattern gate of a 930 Turbo, nor the five-speed symbol of the 3.2 Carrera with first gear in top left, but first was bottom left on a dogleg and reverse was immediately above it.
 
The flat six fired up with that familiar rumble and we eased away from the forecourt, but that’s where the similarity with other 911s I’d driven ended. The original CTRs weighed around 1,150kg depending on the spec (this one had air conditioning). They are rear-wheel-drive and there’s no ABS or interventional electronics of any kind, just the twin-turbo engine developing 469bhp and 408lb/ft torque (compared to 317lb/ft for a 930 Turbo), transmission, tyres and brakes. Launching the Yellowbird from standstill in pursuit of some acceleration times against the stopwatch is a brutal experience. It’s one of those ‘don’t forget to breathe’ moments because everything from then on happens so quickly, it’s hard to keep up.
 
First gear, 7,000rpm and 50mph are over in a flash, so be prepared to shift firmly into second. The gearbox has that heavy synchromesh of the 930 or 915 transmissions and there’s no rushing things. Being careful not to touch reverse on the way through the gate, second gear is when the CTR gets into its stride and the rate of acceleration is suddenly colossal, with 86mph coming up in around six-and-a-half seconds and 100mph about a second later. Breathe, but there’s no respite from the explosive and unrelenting pace which shows no sign of abating.
 
Then 125mph comes up a few seconds after that and, incomprehensibly, the CTR just keeps rushing towards the horizon, the speed increasing at a bewildering rate with that flat, intoxicating blare of the twin-turbo flat six effectively overwhelming any other sound. The CTR feels a tad short-geared because it is slightly and, as Ruf says, the record-breaking top speed of the original was curtailed by the rev limit rather than aerodynamics. For that reason, the pace might easily catch the unwary, with objects appearing in the far distance suddenly looming large in the windscreen as the usual unconscious assessments of speed and distance become almost futile.
 
Launching the Yellowbird from rest needs a rethink too. Acceleration test runs in factory 911s back then could be quite tricky in the dry. Traction was well matched to torque and, rather than some wheelspin acting like a clutch for a smooth getaway, the tyres would grip, bogging the car down. That isn’t what happens in the CTR. Despite plenty of grip from the 10-inch-wide rear tyres, merely flooring the throttle in first is enough to spin the wheels uselessly and taking second soon after launch pays off. It’s best to be deliberate with the second gear change, resisting the temptation to snatch or rush the lever through the gate and being certain the gear is fully engaged. Second to third demands the same treatment and, while you’re being slammed into the driving seat, there’s a strong sense of having a tiger by the tail.

 
MAKING LIGHT WORK

To give the performance some context, the current 911 Turbo S develops 641bhp and weighs 1,640kg. It’s also packed with electronic safety systems to protect the driver from getting into trouble. On a like-for-like basis in terms of what ‘kerb weight’ means, the CTR weighs only 1,150kg so the difference is 490kg – almost half a tonne.
 
Power-to-weight ratio is a good way to compare performance rather than relying on power figures alone. Thanks mainly to its simplicity and light weight, the CTR bettered most ‘traditional’ supercars of the day in this respect. The Yellowbird has a power-to-weight ratio of 407bhp per tonne, the Ferrari F40 has 375bhp per tonne and today’s 911 Turbo S has 390bhp per tonne. Ferrari’s Testarossa was bettered by almost 100bhp per tonne.
 
Then there’s the supporting technology. There isn’t any in the CTR – no PDK transmission, no launch control and no traction or stability control, just raw power matched to a well-considered chassis, tyre choice and slick aerodynamics. The brakes, which are based on those of the Group C 962, are phenomenal. With the tactile feedback through the pedal of a true racing brake and producing exceptional stopping power, they are a comfort and are easily capable of dealing with the car’s wild exuberance.
 
Despite the stupendous performance, the CTR still feels like a 911 and corners like one, though perhaps with more progressive turn-in, no washout and tightening the line with judicious application of the mighty powerplant. Turbocharged engines of the 1980s were nothing like those of today, which suffer virtually no discernible lag. Variable geometry technology giving a crisp response from a turbo that may be spooling down or cruising didn’t exist and lag is something to be reckoned with by modern standards. Despite that, the engine in the Yellowbird still felt gutsy at 2,500rpm, would get going at 3,500rpm, and really started to sing at 4,000rpm.
 
Like the factory 930 Turbo, it’s a kind of ‘back-to-front’ turbo response, getting into its stride at relatively high revs where the emphasis these days is for boost to begin as low down the rev range as possible. A pleasing advantage of old-school turbocharging is the slingshot feel it gives as the boost pressure builds up, as if you are on the end of a giant bungee cord. With all that going on, the CTR, which was designed and built to achieve the highest speed possible, feels solid and stable at speeds well into three figures and there’s no waywardness of that light front end.

 
PORSCHE, PERFECTED

CTR stands for ‘Group C Turbo Ruf’, a nod to the legendary 962 Group C car, and its powerplant is designed to resemble that of the Le Mans racer. Surprisingly, the engine is not based on the 930 Turbo engine but that of the 3.2 Carrera, which itself had been elevated beyond the SC by adding the longer stroke (74.4mm) 930 crankshaft, raising the capacity from 3.0 litres to 3,164cc. Increasing the bore from 95mm to 98mm opens the capacity of the CTR to 3,366cc or, in round figures, 3.4 litres.
 
“The 3.2 was the base engine, but the intake turbocharger manifolds were our own and so were the exhaust headers,” Ruf explained. “The oil lubrication system was ours and so was the suction system for the turbochargers, which had to be drained of oil by the pump.” The turbochargers were also specified by Ruf and made by the same world-famous firm which also supplied the turbocharger for the factory 930 Turbo. “There was pretty much only one supplier at the time,” he recalls, “and that was Triple K – Kühnle, Kopp & Kausch – which today is BorgWarner.”
 
The Motronic injection and ignition system had to be re-mapped in conjunction with Bosch but, although achieving the power was straightforward enough, Ruf said it took a year of tuning work to make the car driveable. The oil tank, which sits in the rear wheel arch area in a normal 911, was moved forward to free up space and rebalance the weight as well. The front brakes were given 330mm rotors, while the four-pot calipers were designed by Ruf to resemble those of the 962 and commissioned from Brembo.
 
Despite appearances, the body shell is not based on the 930 Turbo. “It wasn’t really a wide body in the sense of the Turbo,” Ruf says. “We widened the Carrera fender flares by one inch on each side because we needed to have larger wheels at the rear – we used a 10-inch wheel – and we had also removed the rain gutters. If we had used the wide body, it would have made too much air resistance.” The arches were crafted in-house, then welded and blended into the body using traditional lead-loading rather than filler. The 10-inch wheels were also designed in-house and complemented by eight-inch rims at the front.
 
Make no mistake, the CTR was designed specifically to win Road & Track’s World’s Fastest Car competition. That would be held at Volkswagen’s Ehra-Lessien test track in northern Germany. Ruf had won it previously in 1984 at a top speed of 186mph with its 930 ‘narrow body’ Turbo BTR (Group B Turbo Ruf) and was invited back in 1987.
 
“We knew after the first event what Road & Track was looking for,” Ruf explains. “At the first event, most participants didn’t know what to expect, thinking it might perhaps just be a nice photoshoot. But, in fact, it was a very serious high-speed run, performed by two very famous racing drivers: Phil Hill and Paul Frère. Having been part of that in 1984, we were well-prepared. We had driven the car on the autobahn, we established what the engine cut-out speed was and we knew we could achieve somewhere over 330kmh [205mph]. With that information, we went to the high-speed event and, sure enough, won it overall.”

 
ONE STEP FURTHER

One of the most intriguing aspects of the Yellowbird is the transmission. The four-speed 915 gearbox of the Carrera 3.2 didn’t have the capacity to handle the Yellowbird’s substantially increased torque. The 930 gearbox was the strongest available, but it only had four gears. Neither gearbox had the ratio spread to achieve the desired top speed, so the team was stuck between the proverbial rock and a hard place.
 
To overcome the problem, Ruf’s chief engineer Joseph Huber designed a modified version of the four-speed gearbox, tucking a fifth gear into the casing. Although closely resembling the original, all the casings were re-manufactured. For all intents and purposes, it was a new gearbox.
 
“It was the Ruf five-speed gearbox that we used on all the Porsche 930s,” recalls Ruf. “A new nosecone had space for the extra gear, which was first gear. Even the bell-housing was shorter to make room for the extra gear and the driving gear ratios were all changed so everything would be in harmony and fit well. It made a big impact and produced a much better car overall. It was also a very successful gearbox in its own right and made us quite famous – people don’t usually design gearboxes!”
 
There was an unexpected bonus during my visit (as if driving the Yellowbird wasn’t enough) and that was being invited to try a prototype of Ruf’s latest creation: a six-speed gearbox which would shortly go into production. In 1987, Porsche introduced a new five-speed gearbox for the 3.2 Carrera which is known today as the G50. Following the success of the modified four-speed, Ruf and his team had an idea: why not take the same approach with the new five-speed and add an extra gear?
 
That’s exactly what happened. By adding a new ‘nose piece’ (or end casing) to the existing transaxle gearbox, it was possible to accommodate the extra ratio. Compared to the Yellowbird transmission (and all pre-1987 3.2s), the shift was smooth and easy to handle. Ruf explained the difference was because although it was a Getrag gearbox, the G50 syncromesh was a BorgWarner design rather than Porsche, as was also the case for the 915. Today, the standard G50 is flaunted in sales literature as being the most desirable, but some drivers who have spent enough time with the curmudgeonly earlier ones might miss the involvement they give.
 
Since the Yellowbird, Ruf Automobile has grown from employing just 47 people to 100. Its current models include the Ruf SCR and the Ruf Rodeo, which are both based on Ruf’s own carbon fibre monocoque, and ‘restomodifications’ like the RCT Conversion based on a 964 and the TurboR based on the 993. The Yellowbird’s successor, the Ruf CTR Anniversary, was launched at the 2017 Geneva Motor Show to celebrate the 30th anniversary of the record-breaking car. It was bang up to date, with a Ruf-designed all-carbon fibre body shell and a 3.6-litre, 700bhp engine that gave it a top speed of more than 223mph. Accelerating to 125mph in nine seconds, it truly pays homage to the original prototype and all 50 of the limited-edition run were sold by 2021.
 
RING THE CHANGES

The story wouldn’t be complete without mentioning the video ‘Faszination on the Nürburgring’. If you haven’t had the pleasure, the film features extended clips of Stefan Roser driving the Yellowbird flat out and sideways in a way that could earn the caption ‘don’t try this at home’. It started out as a promotional video for the company recorded on VHS tape that was made when the Nürburgring hadn’t gained the cult status it has today, but ended up almost defining the concept of a car video ‘going viral.’
 
Ruf explained the background and the reason for making it. “The video happened in 1989, the year you came to visit. It was the spectacular run on the Nürburgring Nordschleife and was just supposed to capture a couple of exciting shots because we wanted to create an image that would not be boring, as so many promotional videos were at the time. From that, we made a full movie of the Nordschleife for hardcore enthusiasts who really wanted to learn more about the famous race circuit.”
 
After returning to base that day in 1989, there was time for some more conversation with the amicable Ruf before we left Pfaffenhausen, still hardly believing any high-performance car could be so perfectly executed and by such a small company. It’s a memory that has endured to this day and, after 36 years and many tests of performance cars later, it still stands out as something special. An already enduring love of that particular era of 911 had been reinforced and I was left with an incurable case of the ‘I wants’ but, needless to say, their value has soared since then. A new CTR cost DM380,000 in 1989, around £321,500 in today’s money, and one made headlines recently by selling for $6,055,000 (£4,522,116) at Gooding & Company’s Amelia Island Auctions. Out of reach for most, perhaps, but not bad for a truly breathtaking experience.