When I test drove the Wuling Starlight a few weeks ago, its impressive driving quality made a deep impression on me. With a price tag under 100,000 RMB, what kind of hardware has Starlight used to build such a cost-effective vehicle? We will find out in this Starlight disassembly session.
Fuel Efficiency is Fundamental, Smoothness Also Matters
Starlight’s goal is clear, which is to compete with BYD Qin PLUS in terms of market share, thus its fuel-efficiency performance is crucial.
Starlight’s 1.5L hybrid-exclusive engine uses the Atkinson cycle, setting the compression ratio at 15.5. High compression ratio allows more complete fuel combustion, achieving better fuel efficiency.
To simply explain Atkinson cycle, it reduces the inlet air volume in the cylinder. Less air volume means lower temperature in the cylinder, which in turn reduces engine knock. Consequently, engine knock is no longer limited by the engine’s compression ratio, hence the octane number of the gasoline used will not need to be too high. The recommended fuel for the Starlight is 92-octane gasoline.
In addition, the Atkinson cycle reduces the volume of gas entering the cylinder, the combustion of the air-fuel mixture is fundamentally more complete, improving thermal efficiency. Reducing the inlet volume also lowers the pumping loss and resistance during the compression stroke, hence achieving higher thermal efficiency. The maximum thermal efficiency this 1.5L hybrid-exclusive engine has reached is 43.2%, which is considerably high in civilian vehicles.
We’ve mentioned that this engine has high compression ratio, which while improving combustion efficiency, can also cause engine knock more easily. On top of the Atkinson cycle, this engine also employs various measures like crankshaft offset technology, low tension piston rings, and low friction diamond-like coating to reduce internal friction of the engine and further improve efficiency. In theory, it would also have better durability.Fuel efficiency is just the start, smoothness is equally crucial. Hybrid models necessitate a switch between electric and fuel power – if not done well, it may cause the same gear shifting jolt seen in fuel cars.
Most hybrid models adopt an oil-immersed multi-disc clutch for meshing. The Starlight uses a single-speed electromagnetic DHT. Its clutch control uses electromagnetic technology. Compared with the traditional mechanical hydraulic transmission, the difference in rotational speed of the front and rear gear plates is controlled within 50 rpm. The most direct feeling is smoother, in the previous test drive experience, you can sometimes hear the sound of the engine starting, but you can hardly feel the power switching.
E-type multi-link suspension that is uncommon in the same price range
Almost all A-category cars valued around RMB100,000 would opt for torsion beam non-independent suspensions to save cost and provide space. However, since they need to balance the up and down bounce of the wheels through a torsion beam to reduce vehicle sway, the two sides of the torsion beam will restrain each other during bouncing, affecting comfort.
The Starlight uses an E-type multi-link independent rear suspension, often seen in Japanese cars. Compared to the torsion beam, the independent elastic components of the multi-link can ensure that different wheels do not affect each other, offering better comfort.
In terms of front suspension, Starlight uses the commonly found McPherson suspension. However, due to the use of three-channel topmounts and vulcanized stabilizer rod bushings, the overall feel of the drive isn’t compromised.
There’s an area in the disassembled suspension that deserves attention. As you can witness in the image, both the steering knuckle and rear bearing seat of BYD are constructed with aluminum alloy, underscoring the Wuling’s commitment to elevating the ride experience.
Both Internally and Externally Safeguarded
For electric vehicles, it’s one thing to ensure external crash safety, while the safety of the internal battery is equally paramount.
BYD comes with a self-developed battery by Wuling. This iron phosphate-based battery solution opts for L-shaped bipolar plates instead of the traditional U-shaped ones to circumvent the risk of internal short-circuit caused by contact between sunken bipolar plates and electrode sheets during vehicle vibration. Furthermore, a ceramic coating was added to the battery separator to improve thermal stability and reduce heat conduction.
Regarding technology for battery packs, the battery uses the “MUST Multifunctional Integrated Structure Technology”. In layman’s terms, this technology integrates the structural beams, side panels, and thermal management system of the battery pack into a MUST functional component. This enhances the structural rigidity and multi-functionality of the battery, including thermal management. According to official claims, the MUST structure design boosts the structural strength of the battery system by over 60%.
For external crash safety, BYD employs a closed-loop design for the A, B, C, and double D pillars, enhancing the torsional rigidity and modal of the white-body vehicle.
In addition, the front bumper beam made of aluminum alloy implies that in case of collision, the front end of BYD can absorb impact more effectively. However, it is always advisable to drive steadily as fixating any damages are cost-intensive.
Conclusion
At the time of writing this article, the official price for BYD was announced to be between 88,800 to 105,800 CNY, corresponding to a fully electric cruising range of 70 to 150 km under CTLC conditions. This price for a green label plug-in hybrid vehicle is truly …A pleasant surprise indeed. Combining the previous test drive and this teardown, I believe that Wuling has put considerable effort into areas such as the use of aluminum alloy materials and new technology development. In actual experience, this set of hardware indeed brings a very comfortable driving experience. Therefore, leveraging Wuling’s extensive sales system and mass base, we look forward to the market performance of Starlight (Xingguang).
This article is a translation by AI of a Chinese report from 42HOW. If you have any questions about it, please email bd@42how.com.