• The ultimate evolution of RUF’s early expertise; a peerless example of extreme analog performance
• A completely documented BTR III developed in personal collaboration with Alois Ruf and Gary Bohrman of Exclusive Motorcars, sole US RUF importer
• Finished in its original special-order Dunkelblau (K5) paintwork and matching trim-to-sample dark blue full leather
• Modified in an evolutionary manner by RUF between 1989 and 1994 to a cost over $250,000
• Powered by a 3.4-liter flat six-cylinder BTR III engine paired to an exclusive RUF six-speed transaxle; retains its original, numbers-matching aluminum engine casing
• Retained by the same owner from 1988 until 2016; fastidiously maintained and superbly presented

The arrival of the BTR marked the beginning of RUF’s global reputation, establishing it as the most highly regarded of Porsche tuning firms. The BTR was inspired by the FIA Group B regulation, using the 930 Turbo body and 935-sourced engine internals as a basis with which to produce a 375-horsepower, 190-mph sports car that was then successfully tested by journalists against the fastest contemporary models from Ferrari, Lamborghini, and Porsche. Widely regarded as the fastest-accelerating road car in the world during production, the BTR was consistently revised until 1993 with performance modifications running from their earliest "BTR I" offerings to the latest and most extreme, the "BTR III."

These BTR III revisions extended the relevance of the model by allowing BTR customers to evolve their cars to keep pace with the fastest supercars of the mid-1990s, as well as newer offerings from RUF themselves. If you were in the market for a truly unique “G-body” Porsche capable of supercar-killing performance, then RUF was the company to call—a fact that becomes obvious upon review of this bespoke and outrageous BTR III offered here.

This car began life as a 1985 3.3-liter “rest-of-world” 930 Turbo Coupe. Porsche factory specifications include special order Dunkelblau (K5) paintwork over a matching trim-to-sample full leather interior complete with sunroof, power mirrors, limited slip differential, rear speakers, Blaupunkt radio, and power sport seats. When the previous owner acquired this car in late 1988, he and Alois Ruf were already well acquainted. Correspondence was immediately begun with Ruf and Gary Bohrman of Exclusive Motorcars in Upper Montclair, New Jersey—the sole US distributor for RUF products. Extensive documentation illustrates the “open-checkbook” nature of this collaboration, which is further evinced by meticulous planning, comprehensive testing, astounding engineering costs, and the highest quality control possible. The result is this very unique RUF BTR III, which is surely one of the fastest, most expensive, and unique creations of the period. Quite simply, no component escaped precise tailoring during this evolutionary build, and the car’s exceptionally improved driving dynamics attest to the vision and superiority of RUF’s technical development.

A TRANSFORMATION BEGINS

In January 1989, the previous owner traveled to Pfaffenhausen to meet with Alois Ruf; the transformation of his 930 Turbo began in earnest shortly thereafter. The first $37,000 of upgrades were ordered from Bohrman in June 1989. Included were the 3.4-liter BTR engine package, five-speed transaxle, intercooler, front sway bar, front spoiler with oil cooler, instrumentation, exhaust, and hydro-variable controls for turbo boost and brake bias. Meanwhile, the owner returned to Pfaffenhausen for another meeting with Ruf about modifications and to test house-built cars. Interestingly, a newer CTR clutch assembly and shocks were added to the order at Ruf’s direct recommendations.

A notarized conversion document shows that the factory tachometer and odometer were replaced by the current RUF-branded units at 8,706 miles in late August 1989. This first conversion was completed at Exclusive Motorcars on 1 September 1989, and brought the car’s BTR I engine rating to nearly 400 horsepower.

BLISTERING ANALOG POWER

By December 1990, this car returned to Exclusive and Bohrman for another $93,000 of progressive RUF upgrades, including the BTR III Motronic reflash, twin-plug ignition, lightweight polyurethane CTR bumpers, 17-inch Speedline wheels, racing intercooler, Quaife “Torque Sensing” differential, six-speed RUF transaxle, hydraulic clutch kit, and 330-millimeter CTR brake kit. At this point the chassis was significantly modified with additional bracing, and the suspension geometry was not only improved with new components but also the bespoke remounting of several assemblies at revised positions upon the chassis. Per the client’s expectations, the engine was bench tested, tuned, and rebuilt to exceedingly high standards ensuring optimal performance. This BTR II conversion was completed in June 1991. Notwithstanding its blistering analog power, the car’s six-speed transaxle and major chassis improvements certainly indicate a level of revision and development noticeably superior to Porsche’s road cars of the time.

BTR III AND BEYOND

Just seven months later, another $54,000 of extreme performance modifications were fitted, easily surpassing even RUF’s “normal” BTR III specifications. At Bohrman’s insistence, the car’s 3.4-liter engine was further upgraded with custom cylinder head modifications and Zytek “Formula One” engine management software. Bespoke camshafts, stainless steel headers, custom intercooler, mufflers, and a modified Garrett T04S turbocharger were also provided by noted Porsche tuner Bob Holcombe of Mode Motorsports Design.

In February 1994, the previous owner again returned for a final $8,000 regimen of improvements which included CTR camshafts and a matching remap of the Zytek software. The resulting performance is totally astounding for the period and remains impressive today. Data on file shows this engine configuration delivers a peak 629 horsepower and 595 pound-feet of torque. Even more impressive, this BTR III tips the scales at 2,840 pounds—more than 100 pounds lighter than the car’s original factory-rated curb weight. For particular clarity, consider that this BTR III is lighter and over 20% more powerful than many of the leading turbocharged supercars of the period, including Porsche’s 959 and Turbo 3.6 (993), the Ferrari F40, Jaguar’s XJ220, and the Bugatti EB110 SS.

A UNIQUE OPPORTUNITY

Additional invoices on file show that the car has been regularly maintained, with routine servicing since the completion of its last tuning session at Exclusive Motorcars in May 1994. After nearly 30 years of fastidious enjoyment, the aging owner finally sold this BTR III to the consignor—a close friend who had doggedly pursued this particular car for many years. The consignor knew that this was his only opportunity to acquire such an incredibly unique, well-sorted, and fully documented RUF conversion.

If not for the RUF badging and its unmistakable wheels, it is the ultimate wolf in sheep’s clothing—as comfortable in city traffic as it is on the open road or track. A simple twist of the boost and bias knobs from the cockpit allow the driver all the performance, or comfort, they desire. The car’s unique engine management system (derived from the Porsche 962) offers superior tractability across the versatile power band. The turbo engages minimal boost quite low, with a predictable yet hair-raising, white-knuckle crescendo rocketing all the way to redline.

Today this BTR III is exceptionally presented with minimal patina, and a high degree of original finishes throughout. Excepting its differential and air conditioning system, all of the car’s original Porsche factory equipment remain intact and functional. The car retains its original special-order Dunkelblau paint and matching leather interior; even the numbers-matching aluminum engine casing remains. The unique undercarriage and suspension have been meticulously detailed by the consignor, who reports a plethora of subtle but important adjustments to the suspension and steering, unnoticeable to the untrained eye, but impactful when behind the wheel.

This incredible BTR III is a once-in-a-lifetime offering for the most astute Porsche collector seeking a fully sorted 911 of classic proportions, which can still compete with the performance of modern sports cars. Both a significant piece of RUF’s history and a usable high-performance sports car, this BTR is designed and built for enjoyment at great speed. It is the original outlaw conceived out of a basic desire for unprecedented performance and executed by the foremost Porsche tuner.

Please note that because this car is a RUF conversion, the exact mileage of the chassis is not known. However, this chassis was fitted with a RUF odometer in 1989, and notarized records exist indicating 8,706 miles on its original Porsche factory equipment at the time. A documented odometer repair occurred at 39,068 miles. An extensive compendium of maintenance invoices on file show consistent mileage entries both before and after the odometer repair. As such, RM Sotheby’s believes that the car’s stated post-RUF conversion mileage is closely approximate to the 43,447 shown on its odometer at time of cataloguing.

To view this car and others currently consigned to this auction, please visit the RM website at rmsothebys.com/en/auctions/az22.