The amazing wizards from the tiny town of Pfaffenhausen, Germany have seen fit to design, from scratch, a 4.5-liter V-8 engine to power their latest Porsche 911-based supercar, the RGT-8. Designing an engine from scratch is probably the only way to get a V-8 into the back of a 911 without butchering the bodywork, and indeed the only major body revision made for the engine’s sake was to extend the engine lid up to the rear window, making the entire engine visible and easier to service. Here are the basic highlights of the engine design, which adheres strictly to the tenets of racing engine design:
The crankshaft is a 180-degree flat-plane design for optimal flow characteristics and a “nervous” racing engine note. Connecting rods are titanium. The valvetrain is arranged spherically around the combustion chamber. Maximum speed is 8500 rpm. The block incorporates all coolant and lubrication passages. All ancillary accessories are directly driven directly by the crank or camshaft, so there are no belts, and most are mounted at the bottom of the engine to lower the center of gravity. Lubrication is dry-sump, with five suction pumps and one pressure pump driven off a common internal driveshaft. There are two windage trays in each gallery, and the oil tank is filled through an opening in the right rear fender as was the case on the 1972 dry-sump 911 RS. The V-8 package is the same height as the boxer, and just 0.8 inch longer. With a different transmission, it could be lowered 2.4 inches in the car. Total dressed engine weight is 88 pounds less than the 3.8L boxer six and is considerably more rigid than the boxer engine, which reduces friction. The engine meets current U.S. EPA and Euro V emissions standards. 542 SAE horsepower at 8500 rpm 369 lb-ft at 5400 rpm
The Ruf 001 engine will be assembled in Pfaffenhausen, from castings produced by “a Formula 1 engine supplier” in Germany. The Rufs say they’ll break even if they sell just 300 engines. Why did the founders Alois and Estonia Ruf decide to build a V-8 for their latest product? “Because I believe the boxer is at its limits for natural aspiration, and I wanted a lighter engine with more power. And with the flat-plane crank it doesn’t sound like a normal V-8, which was important to me.” Other changes to the car include new more voluptuously curved front fenders, made of carbon fiber, and an instrument cluster that resembles that of a 550 race car.
No acceleration numbers have been released as of yet, as the engine is still under development. Orders are being taken now for 2011 delivery, as there is still some dynamometer durability and testing work to be completed. The new engine is said to be just as easy to service (easier in some respects) than the boxer six, and it will be warranted for three years and unlimited miles. Pricing has yet to be set, but expect it to be around 220,000 Euros ($300,000). Parked just a couple hundred yards away on the Geneva show floor from the near million-dollar Hispano-Suiza rebodied Audi R8, that strikes us as quite a bargain for history’s first proper eight-cylinder 911.