One of the reasons Porsche has been able to sell the 911 for 50 years is because they know how to keep their customers coming back. Porsche has been committed to not only building a great sports car but building relationships that lasts for generations. A relationship that like a car, can be pasted down from father to son. One example of this commitment to generational relationships would be the Porsche Classic workshop. It is a special workshop, separate from the production factory, that stores and rebuilds parts for the older models Porsche cars. Even though Porsche is not legally obligated to keep producing parts for cars older than ten years, they realize that some of their customers keep the cars for a long time. Either as a daily car, a collection piece or saving it to pass down to their children or grand children. 911s from the air cooled era have seen the auction prices sky rocket at auctions.
911s affordable and easy to maintain. You can go to the normal Porsche dealer and order the parts from the Porsche Workshop and have someone at the dealer install it for you. There is no need for a third party mechanic or a classic parts dealer. Porsche uses a mix of employees for their Classic Workshop. Some of the craftsmen have been working at Porsche since the sixties while others only just finished their apprenticeship. Meaning that the old techniques like manually pressing the metal for the body panels have to be used to recreate these parts. This makes the Classic workshop very expensive for Porsche to run but they see it as investing in the peace of mind for customers. The current buyer will be comforted by the high resale value and the reliability while the classic owner will be not be afraid to enjoy his car out of fear that parts will be hard and expensive to come by. Porsche has also been offering the Porsche Sport Driving School for 40 years. This is a way for Porsche to show their customers how to get the most out of their cars on a race track and teaching them techniques to help them be more competitive. Porsche would employ retired Porsche racers to be spokespersons and a driving instructors. Porsche uses every opportunity to get someone like Jeff Purner or Mark Lieb talking about their cars and the driving experience because these people are well respected in the motor racing community and their opinions are respected.
The inductor (the primary) stores this energy in its magnetic field with its lines of force cutting into the secondary coil (another inductor) and induces a voltage into it. Once the capacitor is empty, the current flow into the inductor stops, and its magnetic field collapses causing a reverse current (now fairly reduced) to flow back into the capacitor again. This back and forth diminishing cycle (called the 'Primary Ringdown') of capacitor to inductor and back, continues until there is insufficient current flowing to keep the spark gap conducting. The point to remember is that every time this primary cycle occurs, more energy has also been transferred away to the secondary, so the primary inductor's magnetic field stores less and less energy on each cycle. Unfortunately every time the spark gap conducts, losses also occur in the form of heat and light, so you want the minimum number of cycles that are consistent with getting all of the available energy transferred to the secondary.
Usually after two, three, or possibly four cycles the majority of the energy has been transferred and the primary current has dropped enough to allow the spark gap to stop conducting (called quenching). Once the spark gap has quenched it allows the capacitor to get a fresh charge and the whole affair can start again. You can see here that doubling the value of C (provided your power source is robust enough) will give you twice the power. But doubling the voltage that the capacitor is charged up to will give 4 times the power, because the voltage value is squared, that's why if you want spark length it's best to go for a higher voltage power source. The toroid on top of the coil acts like a capacitor with respect to the surrounding ground. This is easier to see in the diagrams below. Fig 1 is the same as Fig 2, because in reality the toroid discharges through the air to earth. This means that the secondary coil (an inductor) along with the capacitance of the toroid also forms a resonant circuit, behaving much like the primary circuit.