Auto manufacturers have individually built some of the greatest cars in history – from the Mercedes-Benz SLS AMG and Porsche 911 to the outrageous Koenigsegg Jesko. In some cases, however, carmakers need some help from other automakers to break a record or just to gain the edge over their main competition.

Whilst many companies share parts, engines, and sometimes entire cars, some companies work together to create brilliant automobiles. Examples of these include the Mercedes SLR McLaren, where the great German marque worked alongside the British company to create one of the coolest supercars ever thought up.

In other cases, one automaker consults with another automaker to solve an engineering problem, which inadvertently creates a car that became a starting point for an entire range of cars, which became known all over the world. As such, here are 10 of the coolest cars produced by multiple companies.

10 Citroën SM

Citroen SM in blue parked next to road for photoshoot
Via Mecum Auctions

The Citroën SM was a grand tourer based on the DS architecture, including the amazing hydraulic suspension system. The car was built during a time when the French marque owned a majority stake in the Italian firm, Maserati. Thanks to this acquisition, Citroën utilized the 2.7-liter V6 (later upgraded to a 3.0-liter) in use in Maseratis of the time.

Citroen SM In Gold Front Quarter View
via Historics

The SM produced 174 hp, however, some owners swapped in a more powerful version of the engine from the Maserati Merak SS, pushing power to a more desirable 215 hp. Even though the SM produced less power than most of its competitors, it had the same top speed and featured a much better ride. The SM is one of the greatest cars to come out of France.

Related: This Is What Makes The Citroen SM Such A Wonderful Car

9 Audi RS2 Avant

Audi RS2 Avant 
via Audi

The Audi RS2 Avant came about as a direct result of the legendary Audi Quattro. The car was based on the Audi 80 Avant platform, fitted with a 2.2-liter turbocharged inline-5 engine, and produced 311 hp and 302 lb-ft of torque. The best thing of all, it was designed in collaboration with Porsche.

Audi RS2 Avant
Porsche

The RS2 made such a massive impact that a road test by British automotive magazine Autocar concluded that in a drag race from 0-30 mph, the RS2 was faster than a McLaren F1. The RS2 was the first Audi RS model, which paved the way for all the RS cars which followed – certainly a car worthy of high praise.

8 Lotus Carlton

Dark Green 1992 Lotus Carlton Parked Near Ocean
via Lotus

The Lotus Carlton is just plainly one of the coolest cars to exist. It was based on a rather boring Opel Omega sedan, before being completely overhauled by Lotus. The British company enlarged the straight-6 engine to 3.6-liters and added two turbochargers to it, resulting in a super-saloon producing 377 hp.

Lotus-Carlton---Rear-Quarter-4
Via WallpaperUp

The Carlton was the second-fastest 4-door in the world in the early 1990s, comfortably sitting at around 180 mph – just behind the Alpina B10 Bi-Turbo. The Lotus Carlton was so incredibly fast that it was involved in several high-speed chases in the UK – specifically after the occupants robbed a bank – without the police getting anywhere near it.

7 Mercedes-Benz 500E

The World Loved The Mercedes 500E
via Grassroots Motorsports

The Mercedes-Benz 500E is the result of a collaboration with one of the best automotive engineering firms on the planet – Porsche. Back when cars were over-engineered, Mercedes’ mechanics wanted to put the massive M119 5.0-liter V8 into a W124 platform Mercedes.

Mercedes 500E on the road
Via Mercedes-Benz

Porsche redesigned the engine bay and most of the front end to fit the V8 but kept the rest of the car looking more-or-less like a normal W124 – save for the subtle wheel-arch extensions. Finally, in 1991, the 500E was ready and launched with 320 hp and 354 lb-ft of torque. Unfortunately, due to the 4-speed automatic gearbox, the top speed was limited to around 160 mph. Still, the 500E is one of the coolest cars to come from either Mercedes-Benz or Porsche.

Related: A Detailed Look Back At The Mercedes-Benz 500E

6 Maserati GranTurismo

2013_maserati_gran_turismo_front-angular-view
Via: Bringatrailer

The Maserati GranTurismo was a car that went from first design to production-ready in just 9 months, a record in the motor industry. The reason for this was that Ferrari did to Maserati what VW did to Porsche, and sold Maserati to FCA, but kept the proposed plans for a new car. As a result, Maserati didn’t have a car, but it kept an engine – the glorious F136 from Ferrari.

successor
via Mecum

Maserati’s engineers went about designing the car and while they were at it, they changed the Ferrari V8 to be a bit more Maserati-esque. The resulting car was the beautiful GranTurismo with its 4.2-liter naturally aspirated V8. The plans Ferrari kept turned into the Ferrari California, which had the same engine. Maserati updated the car a few years after launch and created the GranTurismo S, which featured a larger 4.7-liter – which, without a doubt, makes the best V8 sound in the history of the automobile.

Related: A Look Back At The History Of The Maserati GranTurismo

5 Lamborghini Huracán

Lamborghini_Huracan_1
Via Wikimedia

The Lamborghini Huracán is an awesome car. It is the smallest car currently sold by the Italian automaker and is fitted with a 5.2-liter screaming V10 engine. This is all good and sound, but every gearhead knows that Lamborghini is owned by Audi – which is probably the only reason why Lamborghini is still alive and kicking.

Lamborghini Huracan Drift
Via Lamborghini

Many of the mechanical components are therefore shared with Audi’s version of the supercar, the R8. To make sure that there isn’t too much competition between the two cars, Audi made the R8 ever so slightly slower and less expensive, with the Huracán still being the preferred choice. Like the Gallardo before it, the Huracán is one of the best Lamborghinis yet.

4 Bentley Flying Spur

Flying Spur V8 - 3
Via: Bentley

The Bentley Flying Spur is currently the fastest saloon car in the world. The Flying Spur Speed is fitted with VW’s twin-turbo W12 engine, capable of 211 mph. The Flying Spur is also available with a twin-turbo V8 and a new hybrid version was recently launched with a twin-turbo V6.

Flying Spur Styling Specification - 8.jpg
Via: Bentley

The Flying Spur was designed and engineered in conjunction with Porsche, who supplies the V8 engine and the 8-speed PDK transmission. The W12 is manufactured by VW for both the Flying Spur and the Continental GT and GTC, whilst the V6 is produced by Audi and is actually from the current generation S6. The Flying Spur Hybrid drivetrain is also shared with the Porsche Panamera 4 e-Hybrid.

3 Toyota Supra Mk5

Front 3/4 view of a blue GR Supra
Via Toyota

This may be obvious by now, but for anyone who didn’t know, the Toyota Supra Mk5 is almost completely designed and engineered by BMW. The car is even built alongside the BMW Z4 roadster on the same assembly line. The Supra shares most (if not all) of the mechanical components found in the Z4, however, the straight-6 engine in the Supra is slightly detuned to not outshine the Z4.

Rear 3/4 view of a blue GR Supra
Via Toyota

Toyota has also released a 4-cylinder version of the Supra, which is on average around $10,000 less expensive, however that kind of defeats the point of having a Toyota Supra. The Supra has now been out since 2020 and already has a huge following – with some who really like the BMW-ness and embrace it, and others who swap the B58 turbocharged straight-6 for a good old 2JZ.

2 Mercedes-Benz SLR McLaren

Mercedes-Benz McLaren SLR -
Via Mercedes-Benz

The Mercedes SLR McLaren, sometimes called the Mercedes-McLaren SLR, was Mercedes’ flagship supercar between 2003 and 2009. The car used mainly Mercedes components, redesigned by McLaren so that they all fit together perfectly. The engine was the Mercedes M155 5.4-liter V8, but for this application, it was supercharged and produced 617 hp and 575 lb-ft of torque.

Mercedes-Benz SLR rear quarter
Via Mecum Auctions

The SLR was an amazing car when it was launched and continued being a competitive car until its discontinuation. Mercedes and McLaren updated the car every year, eventually adding the 722 Edition in commemoration of Sir Stirling Moss’ victory of the 1955 Mille Miglia in a number 722 Mercedes 300 SLR. The car had upgraded mechanical bits and the engine was also uprated to 650 hp and 605 lb-ft of torque.

Related: Mercedes-Benz SLR McLaren: Costs, Facts, and Figures

1 McLaren F1

McLaren F1 on track
McLaren

Finally, this car is probably the best and most famous automotive collaboration of them all. Designed by Gordon Murray and engineered by McLaren and BMW, the McLaren F1 was the fastest production car in the world – a title it held for nearly 12 years. The McLaren F1 is currently still the fastest naturally aspirated production vehicle in automotive history – an accolade it has clung onto for nearly 30 years.

McLaren F1 - Rear
Via NetCarShow

The McLaren F1 is fitted with a 6.1-liter BMW S70/2 V12, producing 618 hp and 480 lb-ft of torque, going through a 6-speed manual transmission to the rear wheels only. The car weighs in at just 2,500 lbs (almost exactly), which helps the car accelerate from 0-60 mph in 3.2 seconds, with the 0-125 mph time happening in less than 10 seconds. The McLaren F1 is one of the best cars ever created and deserves to be a poster car.