Mid-engine design
Encyclopedia
A mid-engine layout describes the placement of an automobile
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

 engine between the rear and front axles. Another term for this is mid-ship.

Benefits

The mid-engine layout is typically chosen for its relatively favorable weight distribution
Weight distribution
Weight distribution is the apportioning of weight within a vehicle, especially cars, airplanes, and trains.In a vehicle which relies on gravity in some way, weight distribution directly affects a variety of vehicle characteristics, including handling, acceleration, traction, and component life...

. The heaviest component is nearer to the center of the vehicle, reducing the vehicle's moment of inertia
Moment of inertia
In classical mechanics, moment of inertia, also called mass moment of inertia, rotational inertia, polar moment of inertia of mass, or the angular mass, is a measure of an object's resistance to changes to its rotation. It is the inertia of a rotating body with respect to its rotation...

 and making it easier and faster to turn the vehicle to a new direction. Also the engine weight is more evenly carried by all the wheels with this layout. As a result, vehicle stability, traction, and ride quality are naturally improved when turning, braking, and accelerating.

Mounting the engine in the middle instead of the front of the vehicle puts more weight over the rear tires so they have more traction and provide more assistance to the front tires in braking the vehicle, with less chance of rear wheel lockup and less chance of a skid or spin out. If the mid-engine vehicle is also rear-drive (as almost all of them are) the added weight on the rear tires can also improve acceleration on slippery surfaces, providing much of the benefit of all wheel drive without the added weight and expense of all wheel drive components. The mid-engine layout makes ABS brakes and traction control systems work better, by providing them more traction to control. The mid-engine layout may make a vehicle safer, since an accident can occur if a vehicle cannot stay in its own lane around a curve or is unable to stop quickly enough. Mid-engine design is also a way to provide additional empty crush space in the front of the automobile between the bumper and the windshield, which can then be used in a frontal collision to absorb more of the impact force to minimize penetration into the passenger compartment of the vehicle.

In most automobiles, and in sports cars especially, ideal car handling
Car handling
Automobile handling and vehicle handling are descriptions of the way wheeled vehicles perform transverse to their direction of motion, particularly during cornering and swerving. It also includes their stability when moving at rest. Handling and braking are the major components of a vehicle's...

 requires balanced traction between the front and rear wheels when cornering in order to maximize the possible speed around curves without sliding out. This balance is harder to achieve when the heavy weight of the engine is located far to the front or far to the rear of the vehicle. Some automobile designs strive to balance the fore and aft weight distribution by other means such as putting the engine in the front and the transmission and battery in the rear of the vehicle. Some of the same benefits are gained, but at the cost of greater moment of inertia
Moment of inertia
In classical mechanics, moment of inertia, also called mass moment of inertia, rotational inertia, polar moment of inertia of mass, or the angular mass, is a measure of an object's resistance to changes to its rotation. It is the inertia of a rotating body with respect to its rotation...

 compared to the mid-engine layout, making it harder and less responsive to turn the vehicle to a new direction.

Another benefit comes when the heavy mass of the engine is located close to the back of the seats. It makes it easier for the suspension to absorb the force of bumps so the riders feel a smoother ride. But in sports cars the engine position is once again utilized to increase performance and the potentially smoother ride is usually more than offset by stiffer shock absorber
Shock absorber
A shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. It is a type of dashpot.-Nomenclature:...

s.

This layout also allows the transmission and motor to be directly bolted to each other—with independent suspension on the driven wheels this removes the need for the chassis to transfer engine torque reaction.

Drawbacks

The largest drawback of mid-engine cars is restricted rear passenger space; most mid-engine vehicles are two-seat vehicles. The engine in effect pushes the passenger compartment forward towards the front axle
Axle
An axle is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to its surroundings, with the wheels rotating around the axle. In the former case, bearings or bushings are provided at the mounting points where the axle...

 (if engine is behind driver). Exceptions typically involve larger vehicles of unusual length or height in which the passengers can share space between the axles with the engine, which can be between them or below them, as in some Toyota vans, large trucks and buses. The mid-engine layout (with a horizontal engine) was common in single-decker buses in the 1950s and 1960s, e.g. the AEC Reliance
AEC Reliance
The AEC Reliance was a single-deck bus or coach chassis with a mid-underfloor-mounted engine, built by AEC in Southall, west London, England between 1953 and 1979. The name had previously been used between 1928 and 1931 for another single-deck bus chassis....

. The Ferrari Mondial
Ferrari Mondial
The final Mondial evolution was 1989's Mondial t . It was a substantially changed model, "spearhead of a new generation of V8 Ferraris", according to Road & Track magazine. It was visually different from preceding Mondial models, the most recognisable being the redesign of the air intakes to a...

 is to date the only successful example of a true mid-engined convertible with seating for 4 and sports car / supercar performance. A version of the Lotus Evora
Lotus Evora
The Lotus Evora is a sports car produced by British car manufacturer Lotus. The car, which was developed under the project name Project Eagle, was launched as the Evora on 22 July 2008 at the British International Motor Show.- Development :...

 with a removable roof panel is anticipated but no definite date is known.

Like any layout where the engine is not front-mounted and facing the wind, the traditional "engine-behind-the-passengers" layout makes engine cooling more difficult. This has been a problem in some cars such as the Porsche 914
Porsche 914
The Porsche 914 or VW-Porsche 914 is a mid-engined, targa-topped two-seat roadster designed, manufactured and marketed collaboratively by Volkswagen and Porsche from 1969 to 1976.- Development :...

, which is air cooled rather than having a front-mounted coolant system. But this issue seems to have been largely solved in newer designs. For example, the Saleen S7
Saleen S7
The Saleen S7 is a limited-production, hand-built, high-performance American supercar developed jointly by Steve Saleen for the initial concept and direction, Hidden Creek Industries for resources and initial funding, Phil Frank for the body and interior CAD design and development, and Ray Mallock...

 employs large engine-compartment vents on the sides and rear of the bodywork to help dissipate heat from its very high-output engine.

Variations

The term "mid-engine" has usually been applied to cars having the engine located between the driver and the rear drive axles. This layout is referred to here as RMR layout. Sports and racing cars typically have this mid-engine layout, as these vehicles' handling
Car handling
Automobile handling and vehicle handling are descriptions of the way wheeled vehicles perform transverse to their direction of motion, particularly during cornering and swerving. It also includes their stability when moving at rest. Handling and braking are the major components of a vehicle's...

 characteristics are more important than other features, such as capacity. Additionally the mechanical layout and packaging of a RMR car is substantially different from that of a front engine or rear engine car.

A subset of Front-Rear when the engine is in front of the driver, but fully behind the front axle line, the layout is sometimes called Front Mid engine Rear FMR layout instead of the less-specific term front-engine. In handling and vehicle layout FMR is substantially the same as FR. Some vehicles could be classified as FR or FMR depending on the factory installed engine (I4 vs I6). Historically most classical FR cars such as the Ford Models T and A would qualify as a FMR engine car. Additionally, the difference between FR and FMR may be as little as a few millimeters of engine protrusion in front of the front axle line as manufacturers mount engine as far back in the chassis as possible. Not all manufacturers use the Front-Mid designation.

FMR layout – Front Mid-engine / Rear-wheel drive

These cars are RWD cars with engine placed between driver and front axle. Typically, however, these cars are referred to as FR cars instead.
  • Aston Martin Vanquish, DB9
    Aston Martin DB9
    -DB9 Volante:The Aston Martin DB9 Volante is the convertible version of the DB9 coupe. It is built by hand in limited numbers and has enhanced styling. It is powered by the same 6.0 litre, DOHC 48 valve V12 as the DB9 and is completed with 470 bhp and a top speed of 186 mph...

     and One-77
    Aston Martin One-77
    The Aston Martin One-77 is a two-door coupé built by Aston Martin.It first appeared at the 2008 Paris Motor Show, although the car remained mostly covered by a "Savile Row tailored skirt" throughout the show, before being fully revealed at the 2009 Geneva Motor Show.There was a limited run of 77...

  • Bentley Continental GT
    Bentley Continental GT
    -Flying Spur:The four door Continental Flying Spur saloon was first displayed at the 2005 Geneva Motor Show. The Flying Spur utilizes most of the technical underpinnings of the Bentley Continental GT, and was introduced to European and North American markets in the summer of 2005...

  • BMW Z4
    BMW Z4
    The BMW Z4 is a rear-wheel drive sports car by the German car maker BMW. It follows a line of past BMW roadsters such as the BMW Z1, BMW 507, BMW Z8, and the BMW Z3. The Z4 replaces the Z3. First generation production started in 2002 at BMW USA's Greer, South Carolina plant, with production of both...

     and Z8
    BMW Z8
    The BMW Z8 was a roadster car produced by German automaker BMW from 1999-2003. It was given the E52 BMW model code.The Z8 was the production variant of the 1997 Z07 concept car, which was designed by Henrik Fisker at BMW's DesignworksUSA in Southern California. The Z07 originally was designed as a...

  • Chevrolet Corvette
    Chevrolet Corvette
    The Chevrolet Corvette is a sports car by the Chevrolet division of General Motors that has been produced in six generations. The first model, a convertible, was designed by Harley Earl and introduced at the GM Motorama in 1953 as a concept show car. Myron Scott is credited for naming the car after...

     (second through sixth generations)
  • Dodge Viper
    Dodge Viper
    The first prototype was tested in January 1989. It debuted in 1991 with two pre-production models as the pace car for the Indianapolis 500 when Dodge was forced to substitute it in place of the Japanese-built Stealth because of complaints from the United Auto Workers, and went on sale in January...

  • Ferrari 599 GTB Fiorano
    Ferrari 599 GTB Fiorano
    The 599 GTB Fiorano is an Italian gran turismo produced by Ferrari. It is the brand's two-seat flagship, replacing the 575 M Maranello in 2006 as a 2007 model....

     and 612 Scaglietti
    Ferrari 612 Scaglietti
    The Ferrari 612 Scaglietti is a grand tourer produced by Ferrari between 2004 and 2010. It is a large two door fastback coupé. The 612 Scaglietti was designed to replace the smaller 456 M; its larger size makes it a true 4 seater with adequate space in the rear seats for adults.The design,...

  • Honda S2000
    Honda S2000
    The Honda S2000 is a roadster that was manufactured by the Japanese automaker Honda Motor Company. It was launched in April 1999 and was created to celebrate the company's 50th anniversary. The car was first shown as a concept at the Tokyo Motor Show in 1995, following which it was launched in...

  • Infiniti G
    Infiniti G
    The Infiniti G is a compact executive/entry-level luxury car produced by Nissan's luxury brand Infiniti. The first two generations of the Infiniti G were sedans based on the Nissan Primera. Beginning with its third generation , the Infiniti G have been rebadged versions of the Nissan Skyline line...

    , Infiniti EX
    Infiniti EX
    The Infiniti EX is a premium-type compact crossover SUV priced below the Infiniti FX. It is based on the same FM platform as the Infiniti G, M, and FX models.- Infiniti EX Concept :...

    , Infiniti M
    Infiniti M
    The "M" nameplate has been used on various mid-luxury cars from the Infiniti luxury division of Nissan.The first iteration was the M30 Coupe/Convertible, which were rebadged JDM Nissan Leopard....

     and Infiniti FX
    Infiniti FX
    The Infiniti FX is a mid-size luxury crossover SUV produced by the Nissan-owned Infiniti luxury vehicle brand since the 2003 model year. The FX replaced the QX4 as Infiniti's mid-size luxury-type SUV, although the QX4 was smaller than the FX. It was released at the same time as its competitors,...

  • Lexus LFA
    Lexus LFA
    The Lexus LFA is a 2-seat exotic sports coupe produced by Lexus as a concept car, "halo" vehicle, racing prototype, and production model. It is the second model in the F marque line of performance vehicles from Lexus, following the IS F...

  • Mazda MX-5
    Mazda MX-5
    The MX-5, also known as Miata in North America and Eunos Roadster in Japan, is a lightweight two-seater roadster, of front-engine, rear-wheel drive layout, built by Mazda in Hiroshima, Japan. The model was introduced in 1989 at the Chicago Auto Show...

     (third generation), RX-7
    Mazda RX-7
    Series 1 is commonly referred to as the "SA22C" from the first alphanumerics of the vehicle identification number. This series of RX-7 had exposed steel bumpers and a high-mounted indentation-located license plate, called by Werner Buhrer of Road & Track magazine a "Baroque depression."In 1980...

    , and RX-8
    Mazda RX-8
    The Mazda RX-8 is a sports car manufactured by Mazda Motor Corporation. It first appeared in 2001 at the North American International Auto Show. It is the successor to the RX-7 and, like its predecessors in the RX range, it is powered by a Wankel engine. The RX-8 began North American sales in the...

  • Mercedes-Benz SLR McLaren
    Mercedes-Benz SLR McLaren
    The Mercedes-Benz SLR McLaren is an Anglo-German grand tourer car jointly developed by Mercedes-Benz and McLaren Automotive, built in Portsmouth and the McLaren Technology Centre in Woking, Surrey, England and sold from 2003 to 2009...

     and SLS AMG
  • Nissan 350Z
    Nissan 350Z
    The Nissan 350Z is a two seat sports car that was manufactured by Nissan from 2002 to 2009 and marks the fifth generation of Nissan's Z-car line. The 350Z entered production in late 2002 and was sold and marketed as a 2003 model. The first year there was only a coupe, as the roadster did not debut...

     and 370Z
    Nissan 370Z
    The Nissan 370Z is a sports car manufactured by Nissan Motors. It was announced on October 29, 2008 and was first shown at an event in Los Angeles ahead of the 2008 Greater LA Auto Show, before being officially unveiled at the show itself...

  • Suzuki Cappuccino
    Suzuki Cappuccino
    The Suzuki Cappuccino is a small 2-door, 2-seater demountable hardtop roadster produced by Suzuki Motor Corporation. The vehicle was designed to meet Kei car specifications for lower tax and insurance in Japan. Weighing just , the Cappuccino is powered by a turbocharged, three-cylinder, 657 cc DOHC...

  • Volvo B10M
    Volvo B10M
    The Volvo B10M is a popular mid-engined bus and coach chassis built by Volvo between 1978 and 2001. It was built as the successor of the B58 and was equipped with a 9.6-litre horizontally-mounted Volvo THD100/THD101/THD102/THD103/THD104/DH10A diesel engine mounted under the floor, near the middle...

  • Toyota Estima and 2000GT
    Toyota 2000GT
    The Toyota 2000GT is a limited-production, front-engine, rear-wheel drive, two-seat, hardtop coupé grand tourer designed by Toyota in collaboration with Yamaha. First displayed to the public at the Tokyo Motor Show in 1965, the 2000GT was manufactured under contract by Yamaha between 1967 and...

  • Most pre WWII front engine-RWD cars.

FM4 layout – Front Mid-engine / Four-wheel drive

This layout, similar to above FMR layout, with engine between driver and behind front axle, adds front wheel drive to become a four-wheel drive.
  • Ferrari FF
    Ferrari FF
    The Ferrari FF is a grand tourer presented by Ferrari on March 1, 2011 at Geneva Motor Show. It is Ferrari's first production four-wheel drive model and has been described as a shooting-brake. It will replace the 612 Scaglietti. The FF has a top speed of and it accelerates from zero to in 3.7...

  • Hummer H1
    Hummer H1
    The Hummer H1 is a civilian off-road vehicle based on the M998 Humvee, which was created by AM General. The vehicle was produced from 1992 through 2006, and was the first of what became the Hummer line...

  • Nissan GT-R
    Nissan GT-R
    The Nissan GT-R is a sports car produced by Nissan released in Japan on December 6, 2007, the United States on July 4, 2008, and the rest of the world in March 2009.-History:...

  • Toyota Previa
    Toyota Previa
    The Toyota Previa, also known as the Toyota Estima in Japan and the Toyota Tarago in Australia, is an MPV or multi-purpose vehicle produced by Toyota Motor Corporation since 1990...

     All-Trac
    All-Trac
    All-Trac was a proprietary full time symmetric all wheel drive system used on a variety of Toyota badged models from 1988 to 2000. It was considered a revolutionary advance for all-wheel drive automobiles into the mainstream consumer market and its electronic/vacuum controlled locking center...

     variant
  • Toyota Van
    Toyota Van
    The Toyota MasterAce is a vehicle that was produced by Toyota and distributed worldwide under several names, with "MasterAce" being the name used in Japan. North American markets received the MasterAce as the Toyota Van...

     4WD variant (first generation)

RMR layout – Rear Mid-engine / Rear-wheel drive

These cars use traditional engine layout between driver and rear drive axle. Typically, they're simply called MR layout cars.
  • Lotus Europa (1st production Rear Mid engined car)
  • Lotus Esprit
  • Lotus Elise
  • Lotus Exige
  • Lotus Evora
  • DeLorean DMC
  • Rover MGF
  • Vauxhall VX220
  • Toyota MR2
  • Pontiac Fiero
  • Porsche Cayman

M4 layout – Rear Mid-engine / Four-wheel drive

These cars uses mid-ship, four-wheel drive
Four-wheel drive
Four-wheel drive, 4WD, or 4×4 is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously...

, with engine between axles.
  • Audi R8
  • Bugatti Veyron
    Bugatti Veyron
    The Bugatti Veyron EB 16.4 is a mid-engined grand touring car. The Super Sport version is the fastest road-legal production car in the world, with a top speed of . The original version has a top speed of...

     and EB110
    Bugatti EB110
    The Bugatti EB110 is a mid-engine sports car from Bugatti Automobili SpA. It was unveiled on September 15, 1991, in both Versailles and in front of the Grande Arche at La Défense in Paris, France, exactly 110 years after Ettore Bugatti's birth....

  • Ford RS200
    Ford RS200
    The Ford RS200 is a mid-engined, four-wheel drive sports car produced by Ford from 1984 to 1986. The road-going RS200 was based on Ford's Group B rally car and was designed to comply with FIA homologation regulations, which required 200 road legal versions be built...

  • Jeep Forward Control
    Jeep Forward Control
    The Jeep Forward Control is a truck that was produced by Willys and then Kaiser Jeep from 1956 to 1965. It was also assembled in other international markets. The layout featured a cab over design.- Design :...

  • Lancia Delta S4
    Lancia Delta S4
    The Lancia Delta S4 is a Group B rally car that competed in the World Rally Championship in 1985 and 1986, until Group B cars were banned from competition by the FIA. The car replaced and was an evolution of the Lancia 037 Monte Carlo. The S4 took full advantage of the Group B regulations, and...

  • Lamborghini Aventador
    Lamborghini Aventador
    The Lamborghini Aventador LP700-4 is a two-door, two-seater sports car publicly unveiled by Lamborghini at the Geneva Motor Show on 28 February 2011, five months after its initial unveiling in Sant'Agata Bolognese. Internally codenamed LB834, the Aventador was designed to replace the ten-year-old...

  • Lamborghini Diablo VT series
    Lamborghini Diablo
    The Lamborghini Diablo is a high-performance mid-engined sports car that was built by Italian automaker Lamborghini between 1990 and 2001. It was the first Lamborghini capable of attaining a top speed in excess of . After the end of its production run in 2001, the Diablo was replaced by the...

  • Lamborghini Gallardo
    Lamborghini Gallardo
    The Lamborghini Gallardo is a sports car built by Lamborghini. The Gallardo is Lamborghini's most-produced model to date, with over 10,000 built in its first seven years of production...

  • Lamborghini Murcielago
    Lamborghini Murciélago
    The Lamborghini Murciélago is a two-door, two-seat sports car produced by Italian automaker Lamborghini between 2001 and 2010. Successor to the Diablo and flagship of the automaker's lineup, the Murciélago was introduced as a coupé in 2001. The automaker's first new design in eleven years, the car...

  • Lamborghini Reventon
    Lamborghini Reventón
    The Lamborghini Reventón is a mid-engine sports car that debuted at the 2007 Frankfurt Motor Show. It is the most expensive Lamborghini road car to date, costing one million euros . Its top recorded speed was recorded in Dubai, UAE at...

  • MG Metro 6R4
  • Panther Solo 2
  • Volvo L3314
  • Volvo C303
    Volvo C303
    Volvo Cross Country C303 is the base model of a range of military vehicles produced by Volvo.The car was developed in the late 60s based on the successful L-3314 series and went into production in 1974. This version was produced both as a 4x4 and a 6x6. An 8x8 was planned but dropped. Engines were...


MF layout – Front Mid-engine / Front-wheel drive

These cars are "mid-ship engined" vehicles, but they use front-wheel drive
Front-wheel drive
Front-wheel drive is a form of engine/transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel drive and...

, with engine in front/parallel to driver. Please note that this layout should not be confused with a "front midships" location of the engine, referring to the engine's center of mass being located behind the front axle centerline in which case this would be a FR layout.
  • Citroën Traction Avant
    Citroën Traction Avant
    The Citroën Traction Avant is an automobile which was produced by the French manufacturer Citroën from 1934 to 1957. About 760,000 units were produced.-Impact on the world:...

  • Citroën DS
    Citroën DS
    The Citroën DS is an executive car produced by the French manufacturer Citroën between 1955 and 1975. Styled by Italian sculptor and industrial designer Flaminio Bertoni and the French aeronautical engineer André Lefèbvre, the DS was known for its aerodynamic futuristic body design and innovative...

  • Citroën SM
    Citroën SM
    The Citroën SM is a high-performance coupé produced by the French manufacturer Citroën from 1970 to 1975. The SM placed third in the 1971 European Car of the Year contest, trailing its stablemate Citroën GS, and won the 1972 Motor Trend Car of the Year award in the U.S. in 1972.-History:In 1961,...

  • Cord 810
    Cord Automobile
    Cord was the brand name of a United States automobile, manufactured by the Auburn Automobile Company from 1929 through 1932 and again in 1936 and 1937....

  • Renault 4
    Renault 4
    The Renault 4, also known as the 4L , is a hatchback economy car produced by the French automaker Renault between 1961 and 1992. It was the first front-wheel drive family car produced by Renault....

  • Renault 5
    Renault 5
    The Renault 5 was first unveiled on 10 December 1971, being launched at the beginning of 1972.The Renault 5 was styled by Michel Boué, who died before the car's release, the R5 featured a steeply sloping rear hatchback and front dashboard...

  • Renault 16
    Renault 16
    The Renault 16 is a hatchback produced by French automaker Renault between 1965 and 1980 in Le Havre, France. The reviewer in the May 1965 edition of the English "Motoring Illustrated" said: "The Renault Sixteen can thus be described as a large family car but one that is neither a four door saloon...

  • Saab Sonett
    Saab Sonett
    The Saab Sonett is an automobile manufactured between 1955 and 1957 and again between 1966 and 1974 by Saab Automobile AB of Sweden. Sonetts shared engines and other components with Saab 96s and 95s of the same era....

     mk1
  • Acura Vigor
    Acura Vigor
    The Honda Vigor is a compact sedan sold in Japan from 1981 to 1995. It was sold in North America from 1992 to 1994 as the Acura Vigor, a mid-size luxury car. It was replaced in North America with the Acura TL and in Japan with the Honda Saber...

     (3rd generation)
  • Acura TL
    Acura TL
    The TL "Touring Luxury" debuted as 1996 model, first with the 1996 2.5 TL available with the 2.5 L 176 hp SOHC 20-valve 5-cylinder engine from the Vigor. The 3.2 TL used the 3.2 L 200 hp SOHC 24v V6 from the second generation Acura Legend. The 2.5 TL was positioned as the...

    only the 2.5 TL
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