If you were to whip up a performance car cocktail, what ingredients would you need? Almost every major automaker has dabbled with this recipe to certain concentrations, and each of them take the principles I’ll lay out in this article to whip up some intoxicating products.
You may not actually consider tires to be part of the recipe during an automaker’s vehicle development process, but in fact tires are specifically chosen or in some cases co-developed with a tire brand during the car’s formative stages. The better the rubber you’ve fitted to your performance car, the better your vehicle will be at transferring power to a road surface and maintaining traction. At the basic level, rubber compound, tread pattern, and tire width significantly play into vehicle grip.
Wider tires means a greater friction patch, but width without a high performance (summer) tread pattern won’t do much for a car’s grip. As for the rubber compound (which is a mixture of rubber and filler), high performance tires use a softer compound for better grip, though at the cost of durability, and in the case of summer tires, all-weather traction.
At the end of the day, it’s a question of what you can live without in the name of performance.
The right tires can turn a mid-level performance car into a supercar’s nightmare by enhancing the vehicle’s grip in corners, traction under hard braking, and power delivery.
Equally as important as a good set of tires is a performance car’s stopping power. What good is a high-powered performance car if it’s not able to stop before the first corner on a track? There are several ways to piece together a high performance braking setup, with some elements costing far more than others.
More complicated are the ways performance disc brakes scrub speed quicker.
One of the ways brakes perform better is by creating slots within rotors to allow hot gases, water and other debris to move off of the face of the rotor. While these types of brake rotors wear faster than solid or cross-drilled ones, they perform far better during high performance driving stints.
Another hardware update comes from larger calipers and multiple pistons. By increasing the size of a friction contact patch (with a larger caliper), and by adding pistons for greater, more even pressure, a car can decelerate much more quickly. Further, using a high-friction, more durable brake pad can cheaply and easily improve braking performance. Higher performance pads use additives such a copper or coke powder (a compound designed to dissipate heat and increase friction) improve durability.
Then there’s the brake fluid and lines. Performance brake fluid doesn’t absorb moisture as easily as lower-spec fluids, so they maintain lubrication levels. As for brake lines, standard rubber ones can swell, decreasing brake fluid pressure. Braided steel lines are not only more durable, they keep even, consistent fluid pressure for optimal stopping power. Finally, improvements can be made with the disc compound. While most brake packages use steel rotors, some ultra high performance setups use ceramic or carbon ceramic rotors that resist heat better than lesser compounds.
While some automakers will immediately jump to power to solve performance deficits, all know that the real issue at hand is a strong power-to-weight ratio. If your vehicle foundation is already as light as possible, then obviously you’ll need to turn to engine enhancements, but in many cases, using lighter construction materials or cutting out superfluous convenience features can rapidly improve a car’s power-to-weight ratio and therefore make it faster all-around.
Not only is carbon fiber extremely strong, but it’s ultra light as well.
Some tactics commonly used, depending on how aggressive the performance car’s intentions, include: removing the rear seats (usually in exchange for a roll bar), replacing door handles for straps, swapping in thin, light sport seats for heavier leather ones, replacing leather and metal trim for Alcantara microfiber, and in some cases, removing “luxuries” like cruise control. There are always more extreme measures to save grams, not pounds, but that’s mostly reserved for racing-spec models.
The alternate method to cutting out weight is replacing core vehicle construction materials with lighter components. One common practice on high-end performance cars is to swap steel chassis materials with carbon fiber ones. Not only is carbon fiber extremely strong, but it’s ultra light as well.
Down the chain, many automakers have replaced steel with aluminum (for example, Ford’s new F-150 saved 700 pounds by applying aluminum body panels instead of steel ones). Automakers have also become creative in terms of bonding metals and creating new composites with the benefits of lightness and strength. At the end of the day, it’s a question of what you can live without in the name of performance. A lighter car will not only be faster in a straight line, it will be easier to manage in the corners, and there won’t be as much force to “act on” with your brakes.
Aren’t we onto power yet? Not quite. Another essential ingredient for a delightful performance cocktail is your suspension tuning. There are some incredibly advanced systems out there these days, but I’ll keep it to the basics. The springs, shock absorbers, and linkages connecting wheels to the vehicle body comprise the suspension. Tuning the setup to be softer or tighter affects the vehicle ride and handling characteristics, but there’s more to it than that. The goal is to keep tires in contact with the road as much as possible, and while a softer suspension setup might lend itself to that purpose, it would also increase body roll or vehicle dive and lessen handling potential.
Spring rates are a big part of how a vehicle handles. In performance designations, higher spring rates mean a vehicle will handle rapid changes in weight transfer better than lower spring rates. On a track, that means vertical and horizontal compression at speed is held better in check.
A common difference between a normal vehicle and a performance vehicle is ride height. Sure, some “stance” vehicles which have no business being on a race track are lowered, but the point of a lowered suspension is to drop the center of gravity, and therefore mitigate weight transfer. Just lowering a car isn’t enough to make a significant difference in handling, but it’s one element. Another critical piece to a high performance suspension setup is damping.
Damping relates to a shock absorber’s resistance or compliance to vehicle travel and suspension movement. Without good damping, a vehicle will settle its sprung weight (weight that’s resting upon the suspension) quickly after movement. Modern suspension systems control fluid in shock absorbers to change damping rates. At the highest end of performance damping are systems like MagneRide, which use magnetically controlled dampers to make micro-adjustments within fractions of a second based on how a vehicle’s ECU communicates performance needs.
Another element of suspension tuning is lateral rigidity. By using thicker sway bars (which connect driver and passenger side suspension components) at the front and rear of a car, a car will handle better by reducing body roll. Pretty much all mid or high-end performance vehicles use independent suspensions, as opposed to solid or “live” axle setups. While solid axles are more durable, an independent suspension leads to greater handling potential by letting each wheel rise or lower without impacting the opposing wheel on an axle, creating more traction in corners. Differentials play into handling performance as well by controlling power delivery based on which wheel or wheels have the greatest traction at a given moment, but I won’t go too in depth with that now.
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