When considering the purchase of models such as the Porsche 996, Boxster 986, or Cayman 987, buyers frequently encounter the issue of the IMS bearing, the intermediate shaft bearing, which has become a notorious defect in Porsche's early liquid-cooled boxer engines. However, this is not the only factor that can lead to a complete engine rebuild in the M96 and M97 models; there is another recurring problem, less immediate and more subtle: bore scoring.
Bore scoring refers to longitudinal scratches on the cylinder walls. Unlike the sudden failure of the IMS bearing, this wear progresses gradually. When the first signs become visible, the damage may already be considerably advanced.
This problem manifests more frequently in larger displacement engines, specifically the 911 Carrera 3.6 and 3.8, as well as the first-generation 987 Cayman and Boxster S 3.4. Although smaller engines can also exhibit wear, they are less prone to this condition. It is important to note that not every M96 or M97 engine is compromised, as there are high-mileage units that remain healthy, just as there are low-mileage engines that already show signs of wear.
Bore scoring is not attributed to a defective part or an intrinsic design flaw, but rather to a combination of variables: cylinder material, piston coating, side loads, operating temperature, and engine lubrication quality. Additionally, factors such as worn injectors, cold starts, short trips, and fuel contamination of the lubricant create ideal conditions for the piston to begin damaging the cylinder wall.
To understand this phenomenon, it is necessary to understand the construction of these engines and the absence of traditional liners in the cylinders. Essentially, bore scoring is a type of damage popularly called 'scratched cylinder,' resulting from a failure in the interaction between the piston, cylinder, and lubrication. The analogy of a cup floating in water illustrates the concept: when the oil film fails to separate the piston from the cylinder and both make direct contact in areas of high tension, a piston scratch on the cylinder wall occurs.
In Porsche M96 and M97 engines, the aluminum piston operates on a surface also based on aluminum, protected by the union of exposed silicon on the wall, the piston coating, and the oil film. If this balance is lost, the piston coating can wear down or flake off, leading to adhesion between the surfaces, with subsequent transfer and removal of material, forming grooves on the wall.
The released particles intensify abrasion, while the scratches compromise ring sealing. Consequently, more oil enters the combustion chamber and more gases escape into the crankcase, accelerating wear. This is a progressive process, where initial damage facilitates the continuation of the problem's advancement.
It is crucial to differentiate bore scoring from minor surface scratches, polishing, or normal operating marks observed in borescope inspections. Diagnosis requires analysis of the appearance, location, and extent of the marks, along with other engine indicators.
Aluminum blocks offer lightness and better heat dissipation compared to cast iron. However, an aluminum piston cannot operate directly against an aluminum wall without protection, as friction causes adhesion and severe wear. The historical solution involves using cast iron liners or replacing them with protective silicon-based alloys, a technique that gained prominence in the 1990s.
There are technologies such as Nikasil, Alusil, and Lokasil. Nikasil is an alloy composed of nickel and silicon carbide, used by Porsche in air-cooled engines and the Mezger family. Alusil uses a cast block with a silicon-rich aluminum alloy, exposing silicon particles on the cylinder surface to aid in retaining the oil film. Lokasil focuses the silicon-rich material only around the cylinders, using porous pre-forms infiltrated into the mold.
Although Porsche employed Alusil in 944/928 and 968 models, for the development of the M96 and M97 in the Carrera, Boxster, and Cayman, the Lokasil coating was chosen. Its operation critically depends on the surface finish, piston coating, adequate clearances, and constant presence of oil. Any failure in these elements can initiate bore scoring.
The incidence of bore scoring varies between the M96 and M97 versions, concentrating mainly in higher displacement engines. One reason is that increasing the cylinder diameter and torque, without drastically altering the block architecture, raises the pressure exerted by the piston on the wall during movement. This explains the higher occurrence in the 911 3.6 and 3.8, as well as the 987 Cayman S and Boxster S 3.4.
Piston coating is vital to prevent direct contact between the aluminum surfaces. Its wear or flaking allows the piston to attack the cylinder wall, initiating grooves. Temperature aggravates the situation, as the differential expansion of pistons and cylinders temporarily alters internal clearances, increasing the load on the surface under certain conditions, especially during heating.
However, none of these factors alone condemn the engine. The problem materializes when these characteristics meet insufficient lubrication. Oil contaminated with fuel, worn injectors, driving in short trips, prolonged idling, and crankcase ventilation failures reduce the protection between piston and cylinder. Therefore, bore scoring must be seen as a systemic failure, not a chronic design defect.
Among the 911s, the most susceptible are the 996.2 and 997.1 Carrera 3.6 and the 997.1 Carrera S 3.8, due to increased displacement and torque. In mid-engine models, the focus is on the 987.1 Cayman S and Boxster S with the 3.4. Smaller engines, such as 2.5, 2.7, and 3.2, can also show scratches, but with lower frequency. Turbo, GT2, and GT3 versions use Mezger engines, with a distinct architecture, and employ Nikasil coated cylinders, unlike the problematic Lokasil setup.
The process begins when the injector is dirty or worn, allowing liquid fuel to reach the cylinder wall, diluting the oil film. Cold starts and short trips also contribute, as fuel can drain into the crankcase, diluting the lubricant. False air intakes can cause the electronic control unit to compensate with more fuel, worsening wall washing.
With the reduction of oil between the piston and cylinder, friction increases, the coating wears down, and scratches appear. Contaminating fuel reduces the protective capacity of the oil. In M96 and M97, bore scoring is more frequent in the second bank cylinders (4, 5, and 6). An accepted theory points to piston offset, which can increase lateral pressure on the second bank. Differences in temperature and coolant circulation between banks can also make the oil film more vulnerable.
In the initial stages, bore scoring does not affect engine performance, maintaining power and without triggering fault lights or showing abnormal oil consumption. As the wear progresses, the symptoms become more evident.
After leaving Eternal, which he led for 18 years, one of India's most successful tech billionaires is making his first major bets on new projects.
Deepinder Goyal plans to introduce the Temple device, which is shaped like a bob, within six months. He stated that this wearable gadget, named after its placement location—the temple/temple area—is capable of tracking the body's metabolic state in real time.
According to Goyal, who gave an interview at his extensive farm in New Delhi, the device will be released as a wellness product backed by peer-reviewed research. The launch timeline could range from six months to a year.
Temple will be the first commercial product from his new venture since February, when he stepped down as CEO of Eternal Ltd., whose business verticals include food delivery, quick grocery delivery, and event ticketing.
Goyal explained that Temple is one of the experiments with risky ideas outside the Eternal group. His scientific project, which began as personal research to understand cerebral blood flow, led to the discovery of a new biomarker he termed 'entropy.' This indicator correlates with metabolic rate, providing deeper insights by measuring changes related to stress, meditation, recovery, sleep, and physical exercise. However, the scientific basis of this device has not yet been confirmed by independent scientists.
The Temple device will cost around $1000 and is primarily aimed at high-performers such as executives, athletes, and founders, rather than the mass consumer. Goyal emphasized that he is creating Temple primarily for himself, and the business is merely a side effect.
Despite Temple entering the already saturated wearable device market, including watches and rings that track heart rate, sleep, and fitness metrics, Goyal argued that these products use heart rate as a proxy for what is actually happening in the body, whereas Temple measures metabolic rate directly. He stated: 'Heart rate was supposed to be a substitute for metabolic rate. We found the real thing.'
In addition to Temple, Goyal also invested $20 million personally in LAT Aerospace. As reported by the Economic Times last March, this aviation enterprise aims to reduce congestion in India's largest cities by developing low-cost, short take-off and landing distance aircraft.
His vision is to create a network of eight-seater aircraft connecting small airfields, allowing passengers to bypass major airports and travel directly between cities, towns, and villages. Acknowledging the complexities of the project related to engineering, regulation, and infrastructure, Goyal noted that he has only a 0.1% expectation of success, but he believes such a network could promote economic activity beyond India's largest urban centers.
Goyal's long-term aspirations extend beyond both ventures. He expressed a desire for Eternal, formerly known as Zomato, to continuously transform rather than remain defined by its current business. He believes that Eternal's goal is to ensure the evolution of its DNA, because 'the moment you think you have reached the top, you are dead.'
Previously, Goyal co-founded Zomato under the name Foodiebay—a restaurant discovery platform that digitized menus and contained reviews. In 2010, it was renamed Zomato and subsequently expanded into food delivery. The company went public in 2021. A year later, Zomato acquired the online grocery store Grofers, which was renamed Blinkit and is now India's largest instant delivery firm. Last year, the group was renamed Eternal.
In the first half of 2026, China's foreign trade demonstrated a year-on-year growth of 16.9%, reaching a volume of 25.47 trillion yuan (equivalent to approximately $3.75 trillion). This marked the first time that trade volume for such a period exceeded the 25 trillion yuan mark, according to official data released on Tuesday.
According to data from the General Administration of Customs (GAC), China maintains its status as the world's largest goods trader amid confident figures. Exports increased by 13.4% year-on-year to 14.73 trillion yuan, sustaining growth for the 11th consecutive quarter. Meanwhile, imports grew by 22.1% to 10.74 trillion yuan, which is 8.7 percentage points higher than export growth rates and contributed to a more balanced development of trade.
In the first half, there was a 3.4% increase in the import of raw materials, including metals and energy resources. Imports of mechanical and electrical products rose by 28%, while agricultural product imports grew by 8.6%.
During a press conference, Wang Jun, Deputy Head of GAC, noted that China's foreign trade maintained a stable momentum in the first half of the year, characterized by strong growth, stable operation, and noticeable progress in stabilizing scale and improving structure.
In the second quarter of the current year, the total volume of imports and exports reached 13.61 trillion yuan, representing an 18.4% increase compared to the previous year, marking the highest quarterly growth rate since the third quarter of 2021. In June alone, trade value grew by 24.2% year-on-year, signifying 17 consecutive months of growth.
Trade with countries participating in the Belt and Road Initiative increased by 14.8% in the first half, reaching 12.97 trillion yuan, accounting for 50.9% of the total foreign trade volume. Trade with neighboring countries jumped by 20.6%, while trade with Latin America, Africa, and the EU showed growth of 16.2%, 19.6%, and 10.2%, respectively. Trade with Central and Eastern European countries also grew by 11% in the first half, extending ten years of continuous growth.
From January to June, private enterprises contributed to 57% of the total trade value, with their imports and exports growing by 17% to 14.53 trillion yuan. Enterprises with foreign investment and state-owned enterprises showed growth rates of 17.1% and 16.8%, respectively.
Eastern regions of China led in trade scale, reaching over 20 trillion yuan in imports and exports, which is 16.5% more and accounts for 78.8% of the national total. Meanwhile, western, central, and northeastern regions recorded growth of 20.3%, 20%, and 8.6%, respectively.
Exports of mechanical and electrical products increased by 20.1% to 9.36 trillion yuan, accounting for 63.5% of total exports, which is 3.5 percentage points higher year-on-year. High-tech product exports soared by 39%, reaching 3.26 trillion yuan, and exports of own-brand goods grew by 25.4%, increasing their share of total exports by 2.4 percentage points.
Wang emphasized that the first-half trade results reflect key characteristics of China's current economic activity: stability, innovation, vitality, and integration with the rest of the world. A new growth stimulus is also gaining momentum: imports and exports of computing equipment, such as electronic components and computer parts, surged by 56.6% in the first half, reaching 5.13 trillion yuan. Furthermore, there was strong export growth in AI-based products, eco-friendly low-carbon goods, and high-end equipment.
In the first half, 267,000 foreign trade enterprises expanded their business into new markets, with the aggregate value of their trade growing by 22.6%, accounting for nearly 70% of the national total, added Wang.
Liu Dalian, Director of the GAC Statistics and Analysis Department, noted that China has long held the position of the world's largest exporter of sports goods, accounting for over 40% of global exports, and many Chinese goods were seen at the 2026 FIFA World Cup. In the first half of 2026, China's export of sports goods and equipment reached 67.53 billion yuan, of which ball exports amounted to 3.08 billion yuan.
In the first half of the year, China's export of home appliances reached 360.96 billion yuan. Among these, against the backdrop of frequent global heatwaves, the export of cooling devices such as air conditioners, electric fans, and refrigerators totaled 107.91 billion yuan, meeting the needs of many households, according to Liu.
Despite external difficulties for foreign trade in the second half of the year, Wang noted that the fundamental foundations of China's foreign trade remain solid, supported by a strong innovative impetus, active market participants, and a high level of openness. He expressed confidence and the ability to maintain positive foreign trade dynamics, adding that customs authorities will continue to strengthen supervision, optimize services, and promote cross-border trade to sustain this positive trend and facilitate the successful launch of the fifteenth five-year plan (2026–2030).
