1988 Ruf CTR image thread

Raven · 23September, 2021

The Ruf CTR (Group C, Turbo Ruf) also known as the CTR Yellowbird or simply Yellowbird, is a limited-production, high performance sports car manufactured by German automobile manufacturer Ruf Automobile. Introduced for the 1987 model year and based on the Porsche 911, the CTR featured an enlarged and highly tuned version of Porsche's 3.2 litre flat-six cylinder engine, lightened body panels, an integrated roll cage (adding chassis stiffness in addition to occupant safety), upgraded suspension and braking systems, a custom-designed transmission, and several unique trim pieces such as polyurethane bumpers, and the use of the side-mounted oil filler (a Porsche feature for the 1972 model year only) necessitated by relocating the oil tank forward to clear the intercooler on that side.

The car received its nickname, "Yellowbird", during testing by Road & Track magazine, whose staff members noted the contrast created by its yellow paintwork against the overcast skies on the day of their photo shoot.^[2]

The CTR (abbreviation of "Group C Turbo Ruf") was based on the 1987 911 Carrera 3.2 as opposed to the 930; Porsche's factory turbocharged version of the 911. The decision to base the car on the Carrera 3.2 was made because of the 3.2's slightly lower curb weight and drag coefficient. Factory body panels including the doors, hood and engine cover were replaced with aluminum pieces, helping to reduce an additional 200 kg (441 lb) of weight as compared to the vehicle's factory curb weight. Efforts to reduce drag, the use of fiberglass front and rear bumpers and a pair of intake ducts on the rear flares to allow airflow to the intercoolers topped the list of body modifications. The rear arches were also slightly increased in width to accommodate the larger Speedline wheels.

In addition to the lighter panels, considerable modifications were made to the engine, including boring the cylinders out to 98 mm (4 in) to increase displacement from 3.2 L (3,164 cc) to 3.4 L (3,367 cc), adding an uprated DME fuel injection system originally designed for the Porsche 962 race car.^[2] A specifically designed turbo system featuring large twin-turbochargers and twin intercoolers were the main highlights of the modifications done to the engine, bringing total output to 469 PS (345 kW; 463 hp) at 5,950 rpm and 553 N⋅m (408 lbf⋅ft) of torque at 5,100 rpm.

At the time, Porsche offered the 911 3.2 with a 5-speed manual transmission, but the 930 featured only a 4-speed manual transmission, chosen because it was the only unit manufactured by the company that could handle the turbocharged engine's high power output. Not content with only four forward gears and unable to satisfactorily modify the 5-speed unit, Ruf chose to use a new five-speed transmission of their own design on the CTR, which also gave them full freedom to customise gear ratios.^[3] An upgraded suspension system, 17 inch Ruf Speedline alloy wheels, 330 mm (13.0 in) diameter Brembo braking system, and Dunlop's Denloc system performance tyres were used.

The company debuted the vehicle at the end of 1987 with pricing set at US$142,900, although that number could vary depending on whether a given customer ordered it directly from Ruf or brought in a car purchased via dealer for conversion. Ruf manufactured only 29 cars from chassis bought from Porsche; about 20–30 cars were built from customers

Specifications[edit]

Ruf rated the CTR at 469 PS (345 kW; 463 hp) and 408 lb⋅ft (553 N⋅m) of torque. It is said that the official power output of 469 PS was the lowest dynamometer reading of all the CTR engines tested while the average figure was closer to 500 PS (368 kW; 493 hp) or even higher.^[4]^[5]^[2]

Much attention was given to aerodynamic considerations, with the body being de-guttered/seam welded and the use of filler panels for the door pillars and 935-style mirrors. Prototype models had NACA-style intercooler intake ducts over the rear fenders (later dropped, as it was discovered that air was pulled out, rather than in, at speed due to a low-pressure area), while later models had additional slots in the rear bumper corners for the air to exit.

Weighing in at 2,535 lb (1,150 kg), the CTR had a 0-60 mph acceleration time of 3.65 seconds and a top speed in excess of 210 mph. Although the Porsche 959 was faster in terms of acceleration to 60 mph, the Yellowbird could outperform all competition when it came to top speed, topping out at 342 km/h (213 mph), a top speed that made it the fastest production car in the world at the time of its introduction.^[4]^[6]^[7]

Technical specifications^[8]^[9][edit]

Engine configuration: Twin-turbocharged SOHC 2 valves per cylinder flat-six engine
Bore X Stroke: 98 mm × 74.4 mm (3.86 in × 2.93 in)
Displacement: 3,367 cc (3.4 L; 205.5 cu in)
Compression ratio: 7.5:1
Power: 469 PS (345 kW; 463 hp) at 5,950 rpm
Torque: 553 N⋅m (408 lb⋅ft) at 5,100 rpm
Redline: 6,800 rpm
Curb weight: 1,150 kg (2,535 lb)
Gearbox: 5-speed manual transmission (6-speed optional)
Tyres: 215/45ZR-17 front, 255/40ZR-17 rear
Layout: Rear-engine, rear-wheel-drive.

The CTR could generally outperform most of the other high performance cars of the time, including the Ferrari Testarossa and Lamborghini Countach.^[10] In addition, despite being slower than the Porsche 959 in accelerating from 0-60 mph, it could outperform the Porsche 959, Ferrari F40 and the Lamborghini Diablo accelerating from 0-100 mph and attain a higher top speed.^[2]^[7]

The CTR was also a highly competent track vehicle, and for several years it held the unofficial lap record at the Nürburgring-Nordschleife track.

Test results by Autocar:

0–30 mph (48 km/h): 1.69 seconds^[6]
0–60 mph (97 km/h): 3.65 seconds^[6]
0–100 mph (161 km/h): 6.71 seconds^[6]
0–150 mph (241 km/h): 14.59 seconds^[6]
0–200 mph (322 km/h): 35.57 seconds^[6]
Standing mile: 27.7 seconds at 304.34 km/h (189.11 mph)^[6]
0–100–0 mph: 11.85 seconds^[6]
0–200–0 mph: 47.20 seconds^[6]

Test results by other magazines:

0–100 km/h (62 mph): 4.1 seconds^[1]
0–200 km/h (124 mph): 10.5 seconds^[12]
Standing 1/4 mile (402 m): 11.7 s at 215 km/h (133.5 mph)^[10]
0–1,000 m: 20.9 seconds^[1]
Top speed: 342 km/h (213 mph)^[7]

reedminor · 23September, 2021

My poster car - and who can forget the video Fascination at the Nurburgring - and test driver "Stefan - the Schwarzenegger of Opposite Lock"?

Justin

Sov · 23September, 2021

5 minutes ago, reedminor said:

and who can forget the video Fascination at the Nurburgring - and test driver "Stefan - the Schwarzenegger of Opposite Lock"?

It looks to be constantly trying to kill him.