The Porsche flat-six engine series is a line of mechanically similar,

naturally aspirated Naturally may refer to: ;Albums * ''Naturally!'', an album by Nat Adderley * ''Naturally'' (Houston Person album) * ''Naturally'' (J. J. Cale album) * ''Naturally'' (John Pizzarelli album) * ''Naturally'' (Sharon Jones album) * ''Naturally'' ...

and

turbocharged In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...

flat-six A flat-six engine, also known as a horizontally opposed-six, is a six-cylinder piston engine with three cylinders on each side of a central crankshaft. The most common type of flat-six engine is the boxer-six engine, where each pair of opposed cy ...

boxer engine A flat engine is a piston engine where the cylinders are located on either side of a central crankshaft. Flat engines are also known as horizontally opposed engines, however this is distinct from the less common opposed-piston engine design, ...

s, produced by

Porsche Dr. Ing. h.c. F. Porsche AG, usually shortened to Porsche (; see #Pronunciation, below), is a German automobile manufacturer specializing in high-performance sports cars, SUVs and sedans, headquartered in Stuttgart, Baden-Württemberg, Germany ...

for almost 60 consecutive years, since 1963. The engine is an evolution of the

flat-four A flat-four engine, also known as a horizontally opposed-four engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the boxer-four engine, ...

boxer Boxer most commonly refers to: * Boxer (boxing), a competitor in the sport of boxing *Boxer (dog), a breed of dog Boxer or boxers may also refer to: Animal kingdom * Boxer crab * Boxer shrimp, a small group of decapod crustaceans * Boxer snipe ee ...

used in the original

Volkswagen Beetle The Volkswagen Beetle—officially the Volkswagen Type 1, informally in German (meaning "beetle"), in parts of the English-speaking world the Bug, and known by many other nicknames in other languages—is a two-door, rear-engine economy car, ...

. The flat-six engine is most often associated with their 911 model, Porsche's flagship rear-engined sports car which has used flat-six engines exclusively since 1963. The engines were

air-cooled Air-cooled engines rely on the circulation of air directly over heat dissipation fins or hot areas of the engine to cool them in order to keep the engine within operating temperatures. In all combustion engines, a great percentage of the heat ge ...

until 1999, when Porsche started using water-cooled engines. In April 2011, Porsche announced the third generation of the 997 GT3 RS with an enlarged 4.0-litre engine having a power output of . The naturally-aspirated 4.0-litre flat-six engine (the largest engine offered in a street-legal 911) was introduced with their 911 (997) GT3 RS 4.0, in 2011. The engine itself uses the crankshaft from the RSR with increased stroke dimensions (from 76.4 mm to 80.4 mm). This change increased the power output to at 8,250 rpm and of torque at 5,750 rpm. giving it a power-to-weight ratio of 365 hp per ton. Only 600 cars were built. At , the engine is one of the most powerful six-cylinder naturally aspirated engines in any production car with a per litre output. Other Porsche models that use flat-six engines are the 1970-1972 Porsche 914/6 (

mid-engine In automotive engineering, a mid-engine layout describes the placement of an automobile engine in front of the rear-wheel axles, but behind the front axle. History The mid-engine, rear-wheel-drive format can be considered the original layout of ...

), the 1986-1993

Porsche 959 The Porsche 959 is a sports car manufactured by German automobile manufacturer Porsche from 1986 to 1993, first as a Group B rally car and later as a road legal production car designed to satisfy FIA homologation regulations requiring at least 2 ...

( rear-engine), and the 1996-2021

Porsche Boxster/Cayman The Porsche Boxster and Cayman are mid-engine two-seater sports cars manufactured and marketed by German automobile manufacturer Porsche across four generations—as a two-door, two-seater roadster (Boxster) and a three-door, two-seater fastba ...

(mid-engine). The

Porsche 962 The Porsche 962 (also known as the 962C in its Group C form) is a sports-prototype racing car built by Porsche as a replacement for the 956 and designed mainly to comply with IMSA's GTP regulations, although it would later compete in the Europ ...

sports prototype A sports prototype, sometimes referred to as simply a prototype, is a type of race car that is used in the highest-level categories of sports car racing. These purpose-built racing cars, unlike street-legal and production-based racing cars, are n ...

also used a

twin-turbocharged Twin-turbo (not to be confused with a twincharger setup, which is a combination of a supercharger and a turbocharger) refers to an engine in which two turbochargers work in tandem to compress the intake fuel/air mixture (or intake air, in the case ...

flat-six engine. These engines have also been used by

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

tuning company RUF in various replica Porsche

sports car A sports car is a car designed with an emphasis on dynamic performance, such as handling, acceleration, top speed, the thrill of driving and racing capability. Sports cars originated in Europe in the early 1900s and are currently produced by ...

Applications

Road cars

Porsche

*1963–present

Porsche 911 The Porsche 911 (pronounced ''Nine Eleven'' or in german: Neunelfer) is a two-door 2+2 high performance rear-engined sports car introduced in September 1964 by Porsche AG of Stuttgart, Germany. It has a rear-mounted flat-six engine and origin ...

**1963-1989 original

**1989-1993

Porsche 964 The Porsche 964 is the company's internal name for the Porsche 911 manufactured and sold between 1989 and 1994. Designed by Benjamin Dimson through January 1986, it featured significant styling revisions over previous 911 models, most prominently ...

**1994-1998

Porsche 993 The Porsche 993 is the internal designation for the Porsche 911 model manufactured and sold between January 1994 and early 1998 (model years 1995–1998 in the United States), replacing the 964. Its discontinuation marked the end of air-co ...

**1997-2006

Porsche 996 The Porsche 996 is the internal designation for the 911 model manufactured by the German automaker Porsche from 1997 until 2006. It was replaced by the 997 in 2004, but the high performance Turbo S, GT2 and GT3 variants remained in production un ...

**2004-2013

Porsche 997 Porsche 997 is the internal designation for the Porsche 911 sports car manufactured and sold by the German automobile manufacturer Porsche between 2004 (as Model Year 2005) and 2013. Production of the Carrera and Carrera S coupés began in early ...

**2011-2019

Porsche 991 The Porsche 991 is the internal designation for the seventh generation of the Porsche 911 sports car, which was unveiled at the 2011 Frankfurt Motor Show on 15 September as the replacement for the 997. The 991 was an entirely new platform, onl ...

**2019–present

Porsche 992 The Porsche 992 is the internal designation for the eighth and current generation of the Porsche 911 sports car, which was introduced at the Porsche Experience Center, Los Angeles on November 27, 2018. Specifications The 992 uses rack-and-pinio ...

*1970-1972 Porsche 914/6 *1986-1993

*1996–present

Porsche Boxster The Porsche Boxster and Cayman are mid-engine two-seater sports cars manufactured and marketed by German automobile manufacturer Porsche across four generations—as a two-door, two-seater roadster (Boxster) and a three-door, two-seater fastba ...

*2005–present

Porsche Cayman Cayman may refer to * Cayman Islands, an overseas territory of the United Kingdom ** Grand Cayman, Cayman Brac, or Little Cayman, three islands that are part of the Cayman Islands * , a British frigate in service with the Royal Navy from 1944 to 194 ...

RUF

Ruf BTR The Ruf BTR (Gruppe B Turbo RUF) is a sports car built by German automobile manufacturer Ruf Automobile. The BTR began production in 1983 and was based on the Porsche 911 The Porsche 911 (pronounced ''Nine Eleven'' or in german: Neunelfer) is ...

* Ruf BTR2 * Ruf CTR Yellowbird *

Ruf CTR2 The Ruf CTR2 (Group C, Turbo Ruf, 2nd generation) was a 2-door sports car built by German automobile manufacturer Ruf Automobile as the successor to the CTR Yellowbird, but based on Porsche's Type 993 generation 911. History Ruf came into the ...

* Ruf CTR3 *

Ruf RGT The Ruf RGT is a sports car made by Ruf Automobile of Germany. __TOC__ First generation (2000–2004) The first-generation Ruf RGT was introduced in 2000 using an engine and chassis based on the Porsche 996. The original 3.6L version could ...

* Ruf RK *

Ruf R Kompressor The Ruf R Kompressor is a sports car introduced in 2006 and built by Ruf Automobile of Germany. Like certain other Ruf models, The R Kompressor was offered both as a complete ground-up car with a unique Ruf VIN or as conversion for an existing 997 ...

* Ruf Rt 12 * Ruf RTR * Ruf RTurbo * Ruf SCR *

Ruf CTR Anniversary The Ruf CTR Anniversary is high performance sports car manufactured by German automobile manufacturer Ruf Automobile. The vehicle made its debut at the 87th Geneva Motor Show in March 2017, exactly 30 years after the original Ruf CTR was introdu ...

* Ruf CTR3 * Ruf SCR 2018 * Ruf Turbo Florio *

Ruf Turbo R The Ruf Turbo R, sometimes stylized as TurboR, is a sports car built by Ruf Automobile of Germany. It is based on the 993 generation Porsche 911 Turbo. It was introduced in 1998 after the discontinuation of the Ruf CTR2, CTR2 (another 993 generati ...

Race cars

* Porsche 914/6 GT *

Porsche 934 The Porsche 934 was a racing version of the Porsche 911 Turbo, prepared to FIA Group 4 rules, similar to the Porsche 935 which was prepared to FIA Group 5 rules. History The Porsche 934 was introduced for the 1976 racing season. It was manufactur ...

* Porsche 934/5 *

Porsche 935 The Porsche 935 was a race car developed and manufactured by German automaker Porsche. Introduced in 1976 as the factory racing version of the Porsche 930, 911 (930) Turbo and prepared for Fédération Internationale de l'Automobile, FIA-Group 5 ( ...

Porsche 936 The Porsche 936 is a Group 6 sports prototype racing car introduced in 1975 by Porsche as a delayed successor to the 917, a five-litre Group 5 Sports Car, and the 908, a three-litre Group 6 Prototype-Sports Car, both of which were retired by ...

Porsche 956 The Porsche 956 was a Group C sports-prototype racing car designed by Norbert Singer and built by Porsche in 1982 for the FIA World Sportscar Championship. It was later upgraded to the 956B in 1984. In 1983, driven by Stefan Bellof, this car est ...

Porsche 961 The Porsche 961 was a racing car built by Porsche and based on their 959 sports car. It was intended for Group B sports car racing, complementing the purpose-built 956 and 962C which ran Group C in the World Sports-Prototype Championship. The ...

Porsche WSC-95 The Porsche WSC-95 (sometimes referred to as the TWR WSC-95) was a Le Mans Prototype originally built by Tom Walkinshaw Racing. It was modified by Porsche from the original Group C Jaguar XJR-14 from which it derived, and run by Joest Racing. Ori ...

Porsche 911 GT1 The Porsche 911 GT1 is a car designed and developed by German automobile manufacturer Porsche AG to compete in the GT1 class of sportscar racing, which also required a street-legal version for homologation (motorsport), homologation purposes. The ...

Porsche 911 GT2 The Porsche 911 GT2 is a high-performance, track-focused sports car built by the German automobile manufacturer Porsche from 1993 to 2009, and then since 2010 as the GT2 RS. It is based on the 911 Turbo, and uses a similar twin-turbocharged engin ...

Porsche 911 GT3 The Porsche 911 GT3 is a high-performance homologation model of the Porsche 911 sports car. It is a line of high-performance models, which began with the 1973 911 Carrera RS. The GT3 has had a successful racing career in the one-make national ...

https://newsroom.porsche.com/dam/jcr:e00c2789-42c7-4dab-a818-a732003194b0/2019_911_GT3_RS_Technical_Specifications.pdf.PDF * Riley MkXI/Riley MkXX/Riley MkXXII/Riley MkXIVI

References

{{Porsche Porsche Flat-six engines Boxer engines Porsche in motorsport Flat engines