25 wistjedatjes

Why the Porsche 918 Spyder uses a top pipe exhaust design

1. Weight reduction
The 918’s exhaust system, because it is mounted on top of the engine and exits straight up, is much shorter than a standard exhaust that would need to exit out the rear. This allows the system to be made from much less material, and take up less space. The exhaust itself is crafted from an extremely thin-walled alloy steel/nickel called “Inconel”; a material that is much more heat resistant than titanium. In fact, Porsche has said that a titanium exhaust would actually be heavier in this application because it would need much thicker walls to withstand the 850+ degree exhaust temperatures created by the car’s high-rev V8 engine. In total, the exhaust system only weighs a paltry 29 Kilograms (about 64 lbs).
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2. Reduced Back Pressure[/b]
While some back pressure is key to a well tuned engine, you generally need to decrease back pressure as the revs increase. And boy does the 918 have revs! In an effort to provide a very free-flowing exhaust system, Porsche reduced the size of the muffler used on the 918’s 4.6 liter V8 to only 24 liters. By comparison, the 991 GT3’s 3.8 liter flat six has to carry around a 48 liter muffler. Tuned not only for performance, but also for aural quality, the 918’s sonorous exhaust note sounds close to perfect to our ears. Besides, with a shorter system and less back pressure, you occasionally witness some pretty amazing blue flames popping out on the overrun. That’s just plain cool.

3. Improved Aerodynamics
A side-benefit to the top pipe exhaust is a smoother aerodynamically flowing full-body under tray. Without clunky pipes, converters, or mufflers hanging down below the engine, the 918 engineers were able to bring the Porsche’s aerodynamics into sharper focus. With no exhaust tips exiting through the rear of the car, Porsche was able to extend the rear diffuser down to meet with that under-body tray to again provide greater aerodynamics.

4. Thermodynamic Air Channeling
When you are dealing with a car that has batteries, electric motors, regenerative braking, and kinetic energy recovery, heat is your absolute worst enemy, and must be avoided as much as possible. Wherever heat is unavoidable, the exhaust for instance, it’s necessary to minimize its effect on the Porsche’s retention of heat. This is, perhaps, the number one benefit of having a top pipe style exhaust system.
In order to minimize heat the most, Porsche designed the engine with the ‘hot side’, the exhaust, exiting toward the ‘vee’ of the engine, and the intakes on the outside. We’ve already stated that the exhaust can exceed 850 degrees in temperature, so it would make sense to get that heat up and out of the engine compartment as quickly as possible.
In conjunction with the top pipe exhaust design, Porsche developed a system that keeps the lithium batteries within their optimal temperature range (about 70 degrees to about 110 degrees). Without this top pipe exhaust, that battery cooling system would have to work much harder, greatly reducing the overall energy efficiency of the car.

So there you have it; four fantastic reasons why Porsche bucked tradition and installed the only top-exiting exhaust system that has ever been seen in a road going car. You know that if Porsche refuses to compromise on its exhaust system, then surely they took the task of engineering every piece of this car extraordinarily seriously. The 918 isn’t just a halo model, it’s the ethos that goes into every Porsche made.

Porsche kennen we vooral van sportwagens en, tja, de Cayenne. Wist je echter dat het Duitse merk al sinds 1931 haar expertise aanbiedt bij elk merk dat daar om vraagt?

Seat Ibiza (Mk1)

Jawel, een geliefkoosde wagen onder de tuningbrigade heeft Porsche-technologie aan boord. Vrij belangrijke technologie trouwens, want zowel de motoren (1.2 en 1.5 benzine) als de aandrijving werd samen met Porsche ontwikkeld. Daardoor kan je onder de motorkap van sommige modellen een blok terugvinden waarop de badge ‘System Porsche’ prijkt. Een badge die Seat destijds 7 Duitse mark aan Porsche kostte per verkocht model.

Lada Samara
Je mag met elke Lada lachen, maar niet met de Samara. Want lachen met de Samara is lachen met Porsche. Nu ja, de Duitsers werden ten hulp geroepen voor de ontwikkeling van de motoren. En hoewel Het Communisme riep dat ze enkel Porsche nodig hadden voor de ontwikkeling van de kop van de motor (voor de rest waren ze uiteraard slim genoeg), wordt globaal aangenomen dat Porsches hulp veel verder ging dan dat. Tof weetje, in 1990 werd Jacky Ickx zevende in Parijs-Dakar achter het stuur van de Samara T3.

Opel Zafira (A)
Nou, die had je niet zien aankomen hé? Porsche werd door Opel bij de ontwikkeling van de eerste generatie Zafira geroepen. Je weet wel, de monovolume van Opel. Wat Porsche juist deed? Wel, zelf spreken ze van ‘complete samenwerking in de ontwikkeling’. Vaag natuurlijk. Wolfgang Dürheimer – nu CEO van Bugatti en Bentley, destijds ontwikkelingchef van Porsche – heeft het specifiek over het Flex7-zitsysteem. Inderdaad, dankzij Porsche kan je met zeven in de Zafira kruipen.

dat porsche de audi RS2 avant super wagon bouwde is alom bekend, maar wist je dat ze ook de voor de limited edition 500E de 5.0-liter V8 motor leverden aan mercedez-benz

More often than not, Mercedes-Benz and Porsche are at odds with one another—trading blow for blow on-track in sports cars or sprinting down the Autobahn in super-SUVs. But that hasn’t always been the case.

The early 1990s weren’t the best of times for Porsche. A German recession had taken its toll on the Stuttgart powerhouse and sales had hit the skids, hard. In order to keep the machine moving, Porsche began looking for more work. Interestingly enough, Mercedes, which could stamp out cars all day long, needed assistance on a low-volume project—an E-Class V8 super-sedan.

Papers were signed, and the built-by-Porsche Mercedes-Benz 500E was born.

Though Mercedes had the final say in its 500E saloon, Porsche handled all the heavy lifting and assembly at its Rössle Bau plant, where it strengthened the base W124 Mercedes chassis. The production process wasn’t what you’d call simple, however. Porsche would then send these partially-built cars to Mercedes for paint and interior work, at which point they’d return to Porsche for the installation of drivetrain components, before going back for delivery prep. The process allegedly took 18 days, but the results were stunning.

The Mercedes-Benz 500E packed a 5.0-liter, 32-valve aluminum V8, which had been knicked from the 500SL roadster, and reworked to generate 322 hosepower and 354 lb-ft of torque. Zero to 60 mph took under six seconds and the quarter mile disappeared eight seconds after that. While pretty darn brisk off the line, the 500E had no problem striding up to its 155 mph limited top speed. Allegedly, these cars are good for about another 15 mph too.

The beauty of the 500E is in the punches it pulls. At a quick glance, there’s little to suggest its Autobahn conquering performance, apart from the bulging fender flares and lowered stance. Inside, the 500E came fitted with all the luxury and woodgrain splendor expected in a posh ‘90s Merc, along with four bolstered Recaro Sportline seats. Further beneath the skin lies more 500SL machinery, found in the 500E’s up-rated brakes and front suspension. In the rear, Porsche affixed a hydraulic self-leveling setup to better sop up those 155 mph bumps.

10,479 Mercedes-Benz 500E sedans were built from 1990 to 1995 (the vast majority between ’91 and ’94), and of those only 1,500 or so officially made it to U.S. shores. This 1992 500E, which recently surfaced on eBay, is one of them, and it dons a pair of sleek OZ racing wheels to further that subtle, intimidating look. If only Porsche and Mercedes could still play so nicely together.

It took 18 days for Porsche to hand build each one of them, and every minute was well spent. It’s one of few I literally would not change in any way. It is an absolutely perfect automobile, and I am sad right now that I am writing this and not driving it.

12 Things You Didn’t Know About The Porsche 959

To say the Porsche 959 is a legend is an understatement. Whereas its archrival, the Ferrari F40, represents a no-holds-barred approach to speed, the 959 blazed a trail of technology that continues to influence the automotive world to this day.

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1. The 959 was originally designed as a rally car, not a sports car
2. It won the famous Paris-Dakar Rally across North Africa
3. With a top speed of 197 mph, it was officially the fastest car in the world…briefly
4. The 959 impacted the future of the 911 more than any 911 ever did
5. A road race-prepped version, called the 961, won its class at the 24 Hours of LeMans
6. There’s a special gear in the transmission purely for off-road use
7. It was the first production car with tire pressure monitors
8. It had active suspension that adapted to the road…in the 1980s
9. Ride hight adjustement: If you were bored of driving on a highway in the world’s fastest car, you could tackle not-so-paved areas without getting out of the car
10. The engine was one of the very first to utilize a complex “sequential” twin-turbo system
11. The 959 was so beloved by powerful people as Bill Gates that congress changed the US federal importation laws
12. The Porsche 959 was built in the same Baur factory as the BMW M1