Introduced in 1989 as the Porsche 911 Speedster, the limited low-windshield 911 was an immediate hit. Taking styling cues from the late 50’s 356 Speedster, the modern version sported both narrow and wide hips, with the wider bodywork coming directly from the 930. For some this special edition 911 would be a collectible, but one owner wanted something much more from the Speedster. From the teamwork at Canepa Motorsports in 1990 and the visionary ideas from Bruce Canepa, perhaps the most powerful and fastest 911 Speedster was born: the 962 twin-turbo Speedster.
Gary Primm, a car collector in his own right, would take delivery of his brand new 1989 Porsche 911 Speedster and drove it a paltry 100 miles, citing its under whelming performance as his reason for only driving it so few miles. Primm met Bruce Canepa through AMG and the two talked about how the Speedster could be improved both in the looks and performance department. As the conversations got increasingly creative and the grand vision began to come into focus, Bruce and Gary realized that this Speedster would be a creation of the ages and would be unmatched for decades.
“I was inspired by the sinister look of the 934 with its wide fender flares and 10” and 13” wheels, and the performance of the twin-turbo 962”. Bruce immediately began to work with Gary on what the scope of the project would look like. Lots of power, excellent handling and being able to stop on a dime all excited Primm and he gave Bruce the green light. Bruce had the spare 962 engine from the Holbert-built 962 which Bruce drove and raced in 1989. With the power module figured out, it was a natural choice to choose 935 suspension and upgraded brakes to add to the Porsche Speedster. With larger wheels and tires to handle the newfound power, factory Porsche 934 bodywork was added in the form of a factory front spoiler and fender flares on all four corners, and a DP wing was sourced in order to fit the large intercooler. Competitive yet subtle, classy and serious all at the same time.
With famed engine builder Jerry Woods tasked with the 962 engine build, Bruce wanted lots of torque and bottom end power with as little turbo lag as possible. With Woods anything is possible and was able to produce a 962 engine for the street with enough power to satisfy even a Group 5 racer. The engine was converted to 3.3 liters by using 100mm pistons and a 70.4mm stroke crankshaft. The twin K26 turbochargers were from Bruce’s own 959S with a special intercooler from Fred Garretson and stainless-steel exhaust system custom fabricated and placed the turbos behind the rear tires. This allows for short primary headers for excellent throttle response, very little lag and better performance. Updated electronics were added, a proprietary twin-ignition system installed and even a prototype fuel injection management that took advantage of the 962’s twin set of staged fuel injectors was included. When not under boost, the engine runs on one set of injectors with the 2nd set coming online once boost builds. This engineering yielded a joy of a car to drive around town with ludicrous acceleration on open roads. The stainless-steel muffler is also custom made, with two tailpipes similar to a 935. While calming the snarling motor just a little bit, the Speedster still sounds like a Group 5 relative. When finished, the engine produced 581 horsepower at 6500rpm with 1.1 BAR of boost with torque at a stout 550 lb/ft, and an absolute mega 650 horsepower at 1.3 BAR. A 28-quart oil tank in the front trunk lubricates and cools the engine, with an accumulator in the rear wheel well that the engine “breathes” into and separates oil and air. The original 962 flat fan was retained with the engine due to its ability to efficiently cool the 962 street engine, sounds amazing and looks the part.
With an interesting engine choice comes interesting engineering challenges. Normally the 962 engine was mid-mounted and now being required to be rear mounted. Canepa designed and fabricated an all new intake plenum and intercooler plumbing while having it fit underneath the DP wing and engine lid. And with all Canepa Motorsports products at the time, it looks as though it was made and delivered from the Porsche factory. The 962-powered 911 transmits all that boosted power through a G-50 5-speed transmission that’s used from a 1989 Porsche 911 Turbo, shortened an inch so it fits in the Speedster chassis. Other engineering challenges included an air conditioning system and a heater in a very small space. Custom headers left no space for heater boxes, so a gas heater from a Porsche rally car was employed. A custom A/C compressor was designed to run in reverse and was mounted on the rear of the engine, but works as well as a factory system and blows ice-cold air at any temperature. With a convertible with 650 horsepower on tap and capable of 200+ miles an hour, the potential speed had Canepa install numerous safety and structural improvements. A set of 4- point seat belts are installed out of necessity due to this car’s amazing cornering capabilities. A low-profile roll bar was added which was welded to the chassis to become an integral part of the steel unibody. A side bar structure was also welded in, along with boxing the rockers and raising the floor level behind the seats, essentially making a monocoque substructure. By devising this incredibly solid structure, the 935 racing suspension could now perform to its full capability.
With modern road surfaces not as perfect as a racetrack, suspension was heavily considered to ensure both the maximum amount of grip and handling but with a comfortable ride. After much deliberation, a torsion bar suspension setup was used. It provides a good ride on all pavement surfaces and able to provide you with as much cornering ability as your fear level allows. Rifle-drilled torsion bars from Stevens Machining were used with 23mm in front and 33mm in the rear. 22mm “Charlie Bar” sway bars from Wrightwood Racing were used along with custom-valved shock absorbers from Bilstein. 935 center-lock hubs were used so the Speedster could use center lock wheels. Armed with BBS 3-piece wheels, 935 brake rotors with Porsche 959 Brembo calipers, the Speedster is one of the best handling street Porsches that Bruce has ever driven.
With the exception of the roll bar, the turbo dial and the 959 speedometer, the cockpit looks like a factory Speedster. With a fit and finish of a factory car, with mechanicals from a 962 combined with a 935, this inspired car will very likely be the only “962 Twin-Turbo Speedster” that will ever exist.
Original writing by Bruce Anderson
Photos by: Canepa Motorsport