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For passenger cars, apart from brand and appearance, the main parameters are essentially six: engine, transmission, chassis, safety, fuel efficiency, and comfort. Each point has several core parameters. Once the price is determined, by keeping an eye on these key parameters, one can buy a car that suits them. If one blindly trusts online reviews and what car salespeople say, they tend to end up buying the car that is best suited for the reviewers and salespeople. Key engine indicators: power, torque. Power corresponds to how fast a car can go. Torque determines how good a car’s acceleration is. Turbocharging can **increase** the engine’s torque, while direct injection can reduce the engine’s fuel consumption. At this point, you might have a question: isn’t the displacement usually mentioned first when talking about engines? Why isn’t the displacement taken into consideration here? The reality is that, with the advancement of technology (especially the widespread use of turbocharging technology), small-displacement engines can now also deliver high power and torque outputs. Specific examples are as follows: It can be seen that, as technology progresses, engine displacement alone can no longer fully reflect an engine’s performance. The performance of Volkswagen’s 1.6 engine is **inferior to that of Ford’s 1.6 engine** ； BYD’s 1.5T engine is also capable of outperforming all naturally aspirated and turbocharged engines with a displacement of 1.6 liters or less. BMW’s 2.0 engine far outperforms all engines with a displacement of 3.0 liters or less; it’s truly an amazing engine. Key indicators for transmissions include: the number of gears. Common types are: single-clutch, dual-clutch, and continuously variable transmission (CVT). Generally speaking, for automatic transmissions, the more gears there are, the better. The current standard for automatic transmissions is 6 speeds, with 7 speeds being slightly better. As for brands like BMW, they use higher-end 8-speed transmissions. For 4-speed or 5-speed transmissions, we should now choose carefully; let them gradually fade into history. The main function of the transmission is to convert the engine’s output into wheel power for the vehicle. If the engine’s power output is 100 and the gearbox’s efficiency is 0.9, then the car’s power performance will be 90 ； If the same engine is paired with a transmission having an efficiency of 0.6, then the vehicle’s power performance will be 60. Chassis key indicators: suspension type, drive type. The suspension is divided into front suspension and rear suspension. The main types of front suspensions are: MacPherson and double wishbone ； The main types of rear suspensions are: multi-link (independent suspension) and torsion beam (non-independent suspension). Common drive configurations include front-wheel drive, front-engine rear-wheel drive, and front-engine four-wheel drive. What are the differences between these suspension and drive methods? Let’s look at the table below: As can be seen from it, the more premium a sedan is, the better the type of suspension it uses, and the more advanced its drivetrain becomes. Characteristics of the MacPherson suspension: Firstly, it’s low-cost; and that’s about it. Characteristics of double-wishbone suspension: Firstly, it provides better wheel fixation and positioning. Based on this type of suspension, sporty tuning can be performed. Features of a torsion beam: Firstly, it has low costs. Secondly, the vehicle’s body sways significantly when driving on poor roads, resulting in poor comfort. Features of independent suspension: The first one is its excellent comfort; when driving on poor-quality roads, it provides a different driving experience compared to a torsion beam suspension. Then, sporty tuning can be carried out on the basis of this suspension system; almost all sports sedans feature independent suspensions. Look at those Accord and BMWs above; even the better cars hesitate to use non-independent suspensions. So, for vehicles with a double-wishbone front suspension and a non-independent rear suspension, it’s pointless to talk about handling performance – it will only lead to ridicule. Whenever I see salespeople or online reviewers saying that the Lavida has good comfort, I just treat it as jokes. Different drive configurations have a significant impact on a vehicle’s handling performance; this is why BMW, which focuses on handling, typically uses front-engine rear-wheel-drive configurations in its vehicles. Characteristics of front-wheel drive: Most of the vehicle’s mass is concentrated in the front, making it difficult to achieve a 50:50 distribution of weight between the front and rear wheels. The rear wheels bear less weight, making the vehicle prone to skidding on slippery surfaces, and it is impossible to fully utilize the vehicle’s handling capabilities. Moreover, since the front wheels have to handle both driving and steering, this reduces their grip, resulting in understeer when turning (the effect being that, when making a sudden turn, the front of the vehicle does not move in the desired direction due to inertia). Advantages of rear-wheel drive: It makes it easier to achieve a 50:50 distribution of weight between the front and rear wheels (this is also one of BMW’s marketing highlights). It has rear-wheel drive, with the vehicle’s traction coming from the rear wheels; this distributes the load from the front wheels and increases the stability limits when taking corners or making rapid direction changes at high speeds (this is manifested as greater lateral support when turning sharply). Meanwhile, the front wheels are responsible only for steering, resulting in less stress on the entire suspension and enabling more precise steering. Safety is divided into active safety and passive safety. Core indicators of active safety: vehicle stability system, braking distance. Key indicators of passive safety: cabin rigidity (weight), seat belts, head restraints, airbags. Active safety: Vehicle stability system – The vehicle stability system is designed to prevent the vehicle from losing control when making sudden turns under various road conditions. For example, in a car without a stability control system, it will lose control only when making a sudden lane change at speeds over 60 miles per hour on good road conditions; on poor road conditions (slippery surfaces), it will lose control even when changing lanes at speeds over 50 miles per hour ； With the vehicle stability system installed, the critical speed at which the vehicle loses control on poor road conditions can be increased to 55 miles per hour. In this way, the vehicle’s safety performance can **be improved**. Braking distance as a measure of active safety: This can be illustrated with data; please refer to the table below. As you can see, the better the vehicle, the shorter its braking distance. The closer, the safer. Body stiffness in passive safety: Key parameter – body weight. It should be noted that, for cars from the same period, the heavier the vehicle, the safer it is. The rigidity mentioned here refers to the rigidity of the cockpit; as for the engine compartment and trunk, it’s better if they crumple as much as possible. The weights of the aforementioned vehicles are shown in the table below: As can be seen, for vehicles from the same period, the more expensive ones are heavier. Generally, in collisions between a good car and a bad one, no matter how severe the collision, the cockpit of the good car will not suffer significant deformation, whereas the cockpit of the bad car may deform or even disintegrate. To prevent it from falling apart, the body’s rigidity must be high. To achieve high rigidity, given the same type of material, more material must be used. Once sufficient material is used, the weight increases accordingly. So, for cars with a power output of just over 10W, if their weight is less than 1.2 tons, it’s better to stay away from them. Seat belts in passive safety: These are essential for survival in the event of a collision. No matter how good a car is, if the seat belts are not worn in the event of a collision, the people inside will definitely get injured. Therefore, the principle for installing seat belts should be to provide one set of seat belts for each person in the vehicle, with three-point seat belts being particularly important. Some compact cars these days feature two-point seat belts in the middle of the back row. If you see a car like that and you plan to have 5 people in it (especially when driving on the highway), it’s better to give up on such a car. Passive safety headrests: The purpose of headrests isn’t merely to provide comfort when resting one’s head while driving; more importantly, in the event of a rear-end collision, they help limit the backward movement of the head, thereby protecting the occupants’ necks from injury. Many compact cars these days lack a headrest in the middle of the back seat, or the headrest is uncomfortable, requiring the use of a neck pillow. For a car like this, if you need to carry 5 people at full capacity regularly, it’s better to give up on it. Passive safety airbags: Airbags are actually used in conjunction with seat belts. Its function is to prevent the human body from directly colliding with interior panels or glass in the car in the event of a collision. One point that needs to be emphasized here is the side air curtain. The position of the side air curtain is exactly between the occupant’s head and the side window. As we all know, whether in the front or rear seats, there is plenty of space both in front of and behind the occupants. In the event of a collision, thanks to the restraint provided by seat belts, it’s unlikely for the occupants’ heads to hit the windshield or the front headrests. However, the side is different; in the event of a collision, due to space constraints and the fact that the lateral restraint provided by seat belts (other than pre-tensioned seat belts) is not very effective, the occupant’s head is prone to hitting the side windows of the vehicle or the deformed vehicle frame during a side collision. Therefore, when choosing a car, side airbags are a very important feature. Taken together, it works like this: in a car equipped only with seat belts, front airbags, and headrests, the occupants suffer only minor injuries during collisions, rear-end impacts, or rollovers, as their heads and limbs merely come into contact with the interior walls of the vehicle ； With airbags, the injuries sustained would be further reduced. Of course, if you don’t wear a seatbelt, then you’re done for. Cost efficiency: This can be divided into two aspects – the first is fuel efficiency, and the second is maintenance cost efficiency. Fuel efficiency: Key parameter – urban fuel consumption. Regarding fuel consumption, one thing must be kept in mind: figures cited on websites, by salespeople, or passed down by experienced drivers are for reference only. The figures released by the Ministry of Industry and Information Technology are relatively objective; comparing the fuel consumption differences between different vehicle models is the most reliable way to make a judgment. Below are the fuel consumption figures for several vehicles published by the Ministry of Industry and Information Technology. It can be seen that the fuel consumption of the BMW 3 in urban conditions is even lower than that of the Lavida 1.6. The fuel consumption of the Fox 2.0 is lower than that of the 1.8. The Jetta seems to have the lowest fuel consumption, but its weight is only 1.1 tons, and its power output is the weakest among the aforementioned models. Cost efficiency of maintenance: You can simply check the maintenance costs on websites such as Autohome or Yiche.com. It’s worth noting that premium brands like Mercedes have reduced their maintenance costs. Comfortability. Key parameters: wheelbase, automatic air conditioning, suspension. The wheelbase determines the interior space of the vehicle. Cars with a long wheelbase will, in any case, have plenty of interior space. Cars with a short wheelbase simply can’t have much interior space, no matter what. The wheelbase is related to the height of the passengers; there is a simple formula for calculating it: Height of 180+ – Wheelbase of 2700+ ； Height 170+ — Wheelbase 2600+ ； Height 160+ — Wheelbase 2500+. By choosing using the method above, you can select a car that is very comfortable to sit in. Of course, a person who is 180 tall won’t feel uncomfortable driving a car with a wheelbase of 2600 for a short period of time. However, if driving a car with a wheelbase of 2500 mm, it becomes uncomfortable, especially for those in the back seat. Automatic air conditioning. The quality of an air conditioner does not depend on how cold it can make the room, but rather on its ability to maintain a comfortable temperature consistently. In this regard, the convenience offered by automatic air conditioning is something that manual air conditioning simply cannot match, especially when there are children in the car during summer. Set the appropriate temperature on the automatic air conditioner, so that children are less likely to catch a cold. Suspension: Independent suspension provides a smoother ride compared to non-independent suspension.

Haha, that’s really comprehensive – great! I’ll learn it slowly; I’ll start with the flowers and then take my time to look at the rest.

The Great Wall Haval H2 and H6 are quite large in size.

The Corolla is your best choice!