Automotive

patrick_y
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My True Sports Car Requirements...

1. Double wishbone suspension. Generally no exception to this rule, unless it's a multi-link suspension that is arranged in a method that is similar to a double wishbone. Porsche 2 door models, BMW M3, and many "popular" sports cars are all "McPherson Strut" suspension cars. This is a very basic suspension design that is easy to design and easy to engineer with only one "A-arm" pivot point at the bottom of the suspension linkages. The better suspension design is a Double Wishbone suspension design, how does this differ with the "McPherson Strut" system? Well, the oversimplified description is that there are two pivot points, an A Arm on the bottom and a smaller V arm on the top. This is much more difficult to engineer because it requires much more space (which would eat into the trunk space on a front-trunk Porsche), it generally costs more to make (although packaging is the bigger issue than cost), it weighs more because there are more components thus components have to be made in aluminum since this is unsprung weight (weight not supported by the suspension which means inertia affects it more), but the main advantage is that it allows the car to have optimal wheel camber on on camber corners AND OFF camber corners. A McPherson Strut gives you disadvantages in OFF-CAMBER corners. This is critical on roads and racetracks with off camber corners (not every road/track has only on-camber corners). Every sports car brand; Aston Martin, Lamborghini, Ferrari, Mercedes-AMG, Bugatti, Koenigsegg, Rolls-Royce (hardly a sports car), Bentley, etc. all use DOUBLE WISHBONE for the front axle and often also for the rear axle as well! And have been using Double Wishbone designs generally for 50+ years. Porsche's 2 door cars are the only ones that have generally not been using the Double Wishbone! Porsche will say they're being different than the rest of the pack in marketing materials, but race car drivers will note that they are slower in certain off-camber corners on certain race tracks because of it. Most sports car brands like Aston Martin, Lamborghini, still have many cars with Double Wishbone FRONT and REAR suspension! Also, true sports cars allow all aspects of the alignment to be adjusted and adjusted easily, most cars do not make it easy to make these adjustments. Camber, toe, and caster (although we almost never touch caster in alignment).
2. Car should obviously be RWD, few exceptions can be considered. I suppose AWD is popular nowadays, but usually steering feel is compromised with AWD cars compared to RWD cars. I've never owned a FWD car - and I don't see any major advantage to owning an FWD car (FWD cars are more efficient, but less performance oriented).
3. Sports cars should have FIXED BRAKE CALIPERS. Generally, there are no exceptions to this rule. There are two types of brake calipers; sliding and fixed. Generally, high performance cars always have fixed. Fixed calipers have pistons on both sides of the caliper. Sliding only has one side pistons. Imagine a pair of scissors; there's a portion where your thumb goes in one hole and your 3-4 other fingers go in the other hole... Now, imagine that your hand is fixed and you only activate the scissors with the thumb - kind of hard to cut thick paper right? Then imagine you use both the thumb and the other fingers to cut, it's a much more controlled experience.
4. Dry Sump. Generally, no exceptions to this rule should be made for optimal engine reliability. A true dry sump system has an external reservoir where at least 30% of the oil is in the reservoir at any given time. Porsches now have this new term called "Integrated dry sump" which is basically a fake terminology. You either have a wet sump (oil pan on the bottom - most cars) and a dry sump (external oil tank/reservoir - sports cars only). The idea is this: when undergoing performance driving in turns, you're turning at 0.8Gs or more. The oil is all sloshed to one side. The pumps can't scavenge the oil properly. If the oil pumps can't scavenge the oil, then it can't spray oil to the critical parts of the engine that need the oil. Then you get oil starvation. Combine this with long fast sweeping turns (that can last several seconds), and you've got critical areas in the engine that are basically rubbing metal on metal for a very long time (several seconds) at very high RPMs. Obviously, this means that the engine is going to have a shortened lifespan, increased oil consumption, imperfect compression (air will leak in the scratches/scoring made), and have bad running characteristics since some areas have really high wear. With a proper dry sump system, there is so much oil in a tank (where G-forces don't affect it) that there is no interruption in oil delivery to critical points no matter how long the curve is.
5. Rack and Pinion steering over recirculating ball. No exception to this rule. This is rarely a problem. And a sports car with recirculating ball is uncommon. So this is almost a non-issue.
6. Generally Mid-Engine engine placement. Exceptions can be made to this rule, but one should understand the dynamic differences before an exception is made. Mid-Engine sports cars are the best. Usually with a longitudinal engine layout. Porsche 911s have rear engines which requires you to think in an unusual way. You have to hit the gas pedal BEFORE the apex of the turn which is very counter-intuitive and illogical. Drivers are generally taught, the more you steer, the less you can accelerate and brake. And if you're in a straight line, you can accelerate and brake as hard as you want. So why would you accelerate more as you turn more (you do this only for a short moment) is unusual and unique to the Porsche 911. While the 911 is Porsche's flagship product, do notice, Porsche's BEST cars have always been mid-engine cars. Like the Porsche 918 and Carrera GT were all mid-engined. Porsche knows mid-engined is the best, but the 911 makes Porsche unique and there are no competitors to the 911. The rear engine in the 911 also allows for a smallish backseat, which is unusual in the sports car industry - making it almost a Grand Tourer/practical sports car.
7. WEIGHT. This is a big one. Generally, sports cars should be under 1500 KG. Few exceptions can be made to the rule. After this, even with wider tires (wider tires can mask the weight imbalance of a car to a degree). Weight is a huge problem. The bigger the weight of the car, the bigger the tires, brakes, etc. all have to be - which adds more weight. But in the world of safety and regulations, weight will inevitably increase. Heavy cars really have much more inertia and are much more resistant to changing direction.
8. Natural Aspiration. Exceptions can be made here. But for the best driving experience, find cars with a flat torque curve, high RPMs, and a delicious 90-degree V8 or 60/120/180 degree V12 soundtrack. The 90 degree V10 is an unusual sound. Not to be disliked - I like it. The V10 at 90 degrees is not perfectly balanced, so weights and balancing shafts are added (these are vestigial parts that add complexity and don't add performance). Naturally aspirated engines generally rev higher, sound better, and give a flatter torque curve.
9. Lightweight unsprung components. Aluminum everything! Aluminum suspension linkages and aluminum subframes. Avoid making exceptions to this rule. Steel parts are heavy. And they really add weight! thus, unsprung components should really be weight optimized. What is the biggest advantage to carbon ceramic brake rotors? It's not the better braking - it's really the reduction in weight! Wealthy sports car owners have never touched a steel brake rotor nor lifted one. But when you feel how heavy those things are - everyone would agree that a significant weight saving here is worth many thousands of dollars/Euros/Pounds to the driving experience. Carbon fiber wheels and forged wheels can sometimes be good choices as they save A LOT OF WEIGHT. I once drove a BMW 545i with very heavy tires. I changed tires that were 1.5 kg lighter, each tire. so around 6kg total. The car felt ENTIRELY DIFFERENT and much more agile. It was a very noticeable difference. The braking performance also increased dramatically!
10. Reliability and product support. Avoid making exceptions here as it really impacts your ownership experience. Machines all need reliability and product support. This is where Porsche used to have an upper hand - no other sports car company was as large as Porsche and had as many dealers and had a reputation for reliability in street applications. Italian cars were notoriously poor in reliability. Now, Ferraris are made in such large quantities that they are able to achieve better reliability. Lamborghini has many mechanical parts shared with Audi - which increases their reliability significantly. A race-car experience center in Las Vegas told me that Lamborghinis and Porsches are the only reliable cars they have - everything else is unreliable.
Now, with these ten rules - and their technical descriptions, I think everyone will understand why some things are done certain ways. Of course, a no compromise approach to all these rules puts you into some very expensive cars, namely Ferrari and Lamborghini branded machines; the more exceptions we make, the more our experience will be dulled. Some cars meet all of these rules but lose out on certain practicalities, for instance a Lamborghini Huracan meets all of these rules and has terrible visibility and terrible storage space. Most cars meet almost all of these rules but miss out on one or two - the Corvette is a great car and meets all of these rules except it's TOO HEAVY (I haven't driven one, so maybe the weight is well masked). The biggest elephant in the room is obviously Porsche, and they make great products - but they violate the first rule - and not for a good reason.