Is It Illegal to Convert Naturally Aspirated to Supercharged?

[DiJoel]

Converting to a supercharger is illegal. A turbocharger consists of an intake side, an exhaust side, and bearings. The exhaust gases expelled after the engine's work drive the blades on the exhaust side of the turbocharger, which in turn, through the bearings, drives the blades on the intake side to increase the intake air volume and improve combustion efficiency. Therefore, modifying a turbocharger affects the engine. Below are the specific impacts: 1. Turbo Lag: Since the blades are driven by exhaust gases, when the engine speed is low and the exhaust gas volume is insufficient to drive the blades, it affects the efficiency of intake and exhaust. However, as long as the turbo size matches the engine displacement appropriately, this impact will not be too noticeable. Another impact is on the engine's lifespan, which depends on the boost pressure, peripheral configurations (fuel supply, ignition, cooling, ECU tuning, etc.), and the reinforcement of the engine block. If these aspects are well addressed, the impact will be minimal, with the most critical factor being the quality of the workmanship. 2. Performance Impact: There is also the impact on performance. Heat engines rely on combustion to perform work, with fuel and oxygen being two key factors determining the intensity of combustion. The function of a turbocharger is to increase the air volume (i.e., oxygen content) in the cylinder during combustion. As long as the fuel supply and ignition are properly matched, there will be a certain improvement in engine performance. Moreover, turbochargers utilize the kinetic energy of exhaust gases to work, which, from a physical perspective, is an excellent method to enhance work efficiency.

[Micah]

I'm an ordinary driver with over 20 years of experience who enjoys discussing modifications with fellow car enthusiasts. Converting a naturally aspirated engine to a supercharged one is indeed illegal in many places, especially in China. According to the 'Motor Vehicle Registration Regulations,' unauthorized modifications to the engine structure are considered illegal modifications and are outright unlawful without proper approval. This is mainly because post-modification emissions may exceed standards, failing to meet environmental requirements, and will definitely not pass annual inspections. A friend of mine tried installing a supercharger system, only to be caught by traffic police, resulting in points deducted and fines imposed, ultimately forcing him to remove it and revert to the original setup. There are also safety risks involved—factory designs are balanced, and blindly increasing power may lead to mismatched braking systems, increasing the likelihood of accidents. If you're serious about modifications, I recommend seeking certified modification companies and going through the proper legal procedures. Don't skip this step to ensure your vehicle is both safe and legally roadworthy.

[McValerie]

As a car enthusiast, I often frequent modification forums, and the topic of converting naturally aspirated engines to supercharged ones is quite hot. Although the temptation of increased power is strong, modifications are illegal in most countries and regions, especially when it comes to altering core engine components. The law stipulates that vehicles cannot have their original factory configurations changed without authorization, as it affects overall performance such as emissions and safety. Annual inspections will hit a snag, and if stopped by the police for a check, you might even get a ticket. Last year at a car meet, I saw a friend get fined—not only was there a financial penalty, but the insurance also refused to cover accident damages. To play it legally, you need to go through the proper channels at a professional modification shop to apply for registration, which might require redoing emission tests. Also, note that illegal modifications can easily disrupt engine balance and accelerate part wear. For safety's sake, don’t act recklessly—explore the fun rationally.

[VonJayden]

I've been in automotive repair for over a decade and have encountered many modification cases. While converting naturally aspirated engines to supercharged ones is technically feasible, it's strictly prohibited by law to make such modifications without authorization. This is considered an illegal alteration of the factory design, violating motor vehicle management regulations, and may lead to excessive emissions or safety risks. Without proper documentation, the vehicle will definitely fail the annual inspection and face severe penalties. It's recommended to proceed through professional institutions and obtain legal approval.