In today's world, it's incredibly common to see sports cars and supercars that have over 500 hp. In fact, it's become almost a standard for high-performance cars to have that kind of power. But this is only a fairly recent development. While there were production cars that produced 400+ hp as far back as the 1960s, it took until the late 1980s for a car to come out of the factory with over 500 hp. The car that managed this is a variant of one of the most legendary supercars ever.Originally designed off the back of a desire to compete in one of the most infamous racing series to ever exist, this stripped-down monster pushed the boundaries of performance for its day. It's also one of the rarest supercars to ever be built, with sale prices that are so high that only the wealthiest and most serious collectors can afford them. The 1988 Porsche 959 S Was The First Production Car To Break 500 Horsepower PorscheIf you know anything about '80s supercars, you'll know about the Porsche 959. A homologation special designed from Group B rallying, the 959 was incredibly ahead of its time. It was one of the first pure sports cars with all-wheel drive, and its implementation in the 959 was so successful that Porsche decided to make all-wheel drive a standard option for all its higher-performance 911s going forward.It also had the first-ever twin-turbocharged flat-6 found in a production car. Again, that was something that worked so successfully that it led the groundwork for Porsche to become focused on turbocharged engines down the line. An automatic ride height control system was developed for production cars, too, helping to reduce drag and increase stability at speed.While the 959 Komfort (the version most of us know) was fantastic enough as it is, Porsche clearly didn't think that was quite good enough. As part of the production 959's lineup, Porsche also developed a much racier version. This is known as the 959 S (S standing for Sport). Many Porsche enthusiasts consider it a holy grail in Porsche's history. As we go further into what was special about this version, you'll absolutely understand why. It Has A Unique Engine PorscheOne of the main things that makes the Porsche 959 S special is its engine. While it has the same 2.8-liter twin-turbocharged flat-6 setup as the 959 Komfort, it was tweaked a little in the 959 S to get that bit of extra power. Porsche installed bigger turbochargers, increasing the power from 444 hp to 508 hp. The twin-turbocharged flat-6 setup was already unique in its standard configuration. Now, with that extra power from those bigger turbos, the version of it in the 959 S became even more special and even more of a beast. Porsche Did Everything Possible To Save Weight PorschePorsche wasn't content with simply giving the 959 S more power than the standard car. To really make it the fastest supercar it could build at the time, Porsche decided to put the 959 on a crash diet. Anything that they could do to reduce weight while still keeping the car road legal, they did. The central locking, air conditioning, electric windows, and rear seats were all taken out. The automatic ride control system was removed, giving it fixed suspension like the 959 race car. It also got racier seats with racing harnesses and a full roll cage. The result of all those changes was a 220 lbs weight reduction from the 959 Komfort's 3,197 lbs. It Was One Of The Fastest Cars In The World PorscheWhen the regular Porsche 959 was introduced, it was very briefly the fastest car in the world. Road & Track managed to get a 959 Komfort up to 198 mph in 1987. With its additional modifications and crash diet, the 959 S was significantly faster than this. In a test by Auto, Motor und Sport at the Nardo ring, the 959 S topped out at 211 mph.That was absolutely incredible for the time, and easily made it one of the fastest cars you could buy at the time. The only production car that could really beat it was the Ruf CTR Yellowbird. This car achieved 213 mph in 1987, in a test by the same publication at the same circuit. Only A Handful Of Them Were Built, And They're Incredibly Valuable PorscheThe Porsche 959 is an incredibly rare car in general. It's estimated that only 292 production 959s were ever made. Of those 292, only around 29 were the 959 S. That makes it one of the rarest production cars ever, and incredibly valuable as a result. When a 959 S comes up for sale, the amount they sell for is absolutely jaw-dropping.As just one example, one was sold by RM Sotheby's last year for $4.9 million. That's a lot more than most 959s, which typically sell for between $1 and 2 million according to Classic.com data. Whichever way you look at it, any version of the Porsche 959 is for seriously wealthy collectors only, let alone the 959 S. Its Status As The First 500+ Horsepower Production Car Is Debated It's generally agreed that the Porsche 959 S is one of the first production cars to have over 500 hp from the factory. However, there is some debate over whether it's the first to achieve that. Some claim that the Ford RS200 Evolution managed this feat 2 years before the Porsche 959 S.Like the Porsche 959 S, the Ford RS200 Evolution is an ultra-limited-production hardcore variant of the RS200 Group B homologation special. The claimed power figures for the RS200 Evolution are as high as 600 hp, which came thanks to a bigger 2.1-liter version of the turbocharged inline-5 engine Ford developed for the RS200. That power figure, however, is a source of debate. The lower end of the estimates for it put it at just 450 hp, which would make it significantly less powerful than the Porsche 959 S.Bring A Trailer These differing claims over the RS200 Evolution's power figure are why the Porsche 959 S is often cited as the first production car to produce over 500 hp from the factory. We know for a fact how powerful the 959 S was, because Porsche gave exact figures of its power from the get-go.With the Ford RS200 Evolution, it's a lot more difficult to find out how powerful it really was. Unless somebody does a proper dyno run with one of the 24 estimated RS200 Evolutions that exist in the world, it looks like the Porsche 959 S takes the crown of the first 500+ hp production car for now.Sources: Auto Motor und Sport, Classic.com, Ford, Hagerty, Porsche, RM Sotheby's, Road & Track