It’s really sporty. Changan Ford brand new Focus 1.5T

　　　　[XCAR test original]

　　　　A few days ago, my colleague Duan Bin spoke highly of the brand-new Focus 1.5T after test driving in Beijing. After reading the article, I was a little dissatisfied. After all, it seems that this is only an official big change. How can there be such a completely new driving performance? Although the Focus car has always been called as a compact sports car, and it has been sought after by many modification enthusiasts, I have also driven the sports version before the modification. The matching of the 2.0L naturally aspirated engine and the dual-clutch gearbox can only be said that different people have different opinions.

　　　　Design dialogue: Duan Bin"What nonsense! Do you dare to try?

　　　　Here, I don’t want to argue with my colleagues. As the saying goes, it’s mules or horses that come out for a walk! So I swung the "little whip" and used professional instruments to spur this brand-new Focus 1.5T model, which is being gradually pushed to the main force by Ford.

　 　 Analysis on the power of 1.5T;

　 　 First of all, the cylinder head and middle cylinder of this engine are mainly made of aluminum alloy. Aluminum alloy material is beneficial to reduce the weight of the finished product, and the metal property with fast heat conduction speed is also beneficial to control the working temperature of the engine, especially for the turbo-engine with high working temperature, the temperature control is particularly important.

　 　 The turbocharging system of Ford’s 1.5T engine is provided by Borg Warner, and its main model is B01, which is a product tailored for small displacement engines. However, in order to improve the response speed of turbocharging system, Ford also applies integrated exhaust system and underwater cooling system in supporting technologies. Then the question is coming! What is an integrated exhaust system? What is the water cooling system?

　 　 On the integrated exhaust and water cooling system;

　　　　In fact, it is not difficult to understand these two technologies. As we know, the working principle of turbocharging is to use the engine exhaust gas to blow the connecting shaft in the turbine housing to make the compressor end work. In the traditional design, it takes a long distance for the exhaust gas to enter the turbine shell from the exhaust end, and the long exhaust gas stroke will inevitably affect the reaction speed of the turbine and cause delay. However, the integrated exhaust system firstly concentrates the engine exhaust gas in the cylinder and sends it into the compressor shell, which greatly shortens the intake stroke, improves the exhaust gas passing efficiency and effectively reduces the occurrence of turbine delay.

　 　 In addition to the improvement of exhaust manifold technology, the Borgwarner B01 turbine equipped in the original car is also specially built for small displacement engines. The electronic transmission device with noise suppression function controls the compressor and impeller, and optimizes the design of bearings and impellers, which has stronger reaction ability.

　 　 Water cooling system:

　　　　So what is the underwater cold design? In fact, this design is very common at present. According to the principle knowledge we have received, the oxygen content density in the air passing through the turbo-charged body will also decrease due to the increase in temperature. If this air is inhaled into the combustion chamber, it will easily knock, which is not conducive to the efficient use of fuel. Therefore, the necessary cooling must be carried out before this part of hot air enters the combustion chamber. At this time, the intercooler we often mention will play a role. The traditional intercooler, which was widely used a few years ago, used the windward side to cool the intercooler after the hot air directly entered the intercooler. However, the intercooler itself occupied quite a lot of engine room space, and put forward higher requirements for the layout of the intake pipe, so the layout of the intake pipe would generally be extended for a long time, which led to the delay increase due to the long intake stroke. However, the underwater cooling design is to arrange water channels in the intake manifold and exchange intake heat by liquid flow, so as to reduce the intake temperature. This design greatly saves the space in the engine compartment, and at the same time gets rid of the problem of long pipeline layout caused by traditional air-cooled cooling, thus shortening the delay.

　 　Test data:

　　　　In the end, this 1.5T engine, code-named CAF479WQ2, can explode up to 240Nm, with a maximum output of 133kW. The data even exceeds that of many 2.0L naturally aspirated engines, and it is slightly improved compared with the 1.6T engine used by Ford before.

　

　 　 Accelerated testing:

　　　　We use the catapult start mode to carry out the acceleration test. During the initial acceleration, the power unit gives people obvious momentum, but the fly in the ointment is that the original comfortable tire has a relatively average grip performance, which leads to obvious slippage and wastes time. However, it is worth mentioning that, although the axle shaft with equal length design is not adopted, the effect of restraining torsion steering of Focus 1.5T is still excellent. In the end, the acceleration time of the new Focus 1.5T is locked at 9.24 seconds.

　 　 Brake test:

　　　　During the braking test, the front suspension of the new Focus suppresses the body posture well, but there is still a slight nodding phenomenon. However, when the brake pedal is slammed, the feedback of the braking system is particularly linear, and neither the driver nor the passenger will feel too violent braking discomfort. In the end, the braking distance of the new Focus 1.5T is 39.55 meters, which is quite excellent compared with the compact model of the same class.

　 　 Pile winding test:

　 　 The adjustment orientation of the suspension system of the new Focus is quite sporty. The front of the car has a strong directivity, and the suspension limit in the process of winding the pile is very high. As long as it is not the wrong big foot to replenish oil, the front of the car will not be pushed out. As the speed increases, the rear of the car will swing, but the feedback given by the whole suspension can make me confident to control its attitude. However, during the whole test process, the body still showed obvious tilting phenomenon, but this will not affect its accurate control feedback.