What to Consider When Buying a Turbocharger

Views 1 Like Comments Comment
Like if this guide is helpful
What to Consider When Buying a Turbocharger

Turbochargers are one of the most powerful upgrades available for motor vehicles. They are a type of forced induction system, which means they compress air and force it into the engine to provide additional horsepower. Turbochargers are produced in many styles to accommodate different vehicles, and one can be found for nearly every type of car on the market.

There are several things buyers should consider while shopping for turbochargers, such as the design of a unit and its materials. There are two primary limiting factors in turbochargers that manufacturers attempt to work through: turbo lag and boost threshold. Several options are available to reduce the effects of these, and buyers should consider all products to find the most efficient turbo.

Turbochargers can be purchased from specialty auto parts retailers and mechanics. They are also available for sale online. Many websites specialise in motor vehicle parts and accessories, including turbochargers, and marketplaces like eBay have product listings from private and commercial sellers. Consider all options to find the best turbochargers available, and look for units to increase the power and performance of a vehicle.

How Turbochargers Work

Buyers looking to purchase a turbocharger should begin by familiarising themselves with the unit's design. Turbochargers increase a vehicle's horsepower by providing the engine with additional air. They are mounted to the engine's exhaust manifold, and their inner turbine is propelled by the vehicle's exhaust. The turbine, in turn, attaches to a compressor that forces pressurised air into the engine. The rate of the turbine is markedly faster than the speed of a standard car engine, and most run at about 150,000 rpms.

Turbochargers can provide an engine with as much as 50 per cent more air, but the specific amount is dependent on the turbocharger and the vehicle it is installed on. In theory, this increased air flow could improve engine power by 50 per cent, though turbochargers suffer from efficiency setbacks. One example of this is the physical restriction of exhaust flow created by the turbine. Most turbochargers improve power by 30 or 40 per cent.

Turbochargers vs. Superchargers

Turbochargers are similar in design to superchargers. They both use forced induction, which means they compress air and force it into the engine. The important distinction between the two is that turbochargers are powered by engine exhaust, while superchargers are mechanically-powered, and attach directly to the engine. As with all mechanical components connected to an engine, superchargers pull horsepower from the engine. As a result, turbochargers are considered to be more efficient, and provide greater gains in engine power.

Materials and Design

An understanding of the different components and materials in a turbocharger can help buyers choose between different products. Materials affect weight and speed, and lighter components produce faster and more responsive turbo units. Light materials can also diminish some of the efficiency troubles related to turbochargers, such as turbo lag. Two of the most important components to consider in a turbocharger are its bearings and turbine blades.

Turbine Blades

The turbine blades in a turbocharger must operate at high speeds to power the unit. Without sufficient exhaust, the turbine blades have difficulty reaching the necessary speeds. This means accelerating vehicles need a moment to activate the turbocharger. One way of resolving this issue is to make the turbine blades as light as possible, and ceramic turbine blades are sometimes used to accomplish this. Consider this option to improve the performance of a turbocharger during acceleration.

Bearings

The turbine shaft in a turbocharger must be able to spin rapidly to power the unit, and standard bearings are not sufficient. Instead, turbochargers use either fluid bearings or high-end, professional-grade ball bearings. Fluid bearings use a thin layer of oil to coat the shaft of the turbo, which reduces friction and also helps keep components of the turbocharger cool during operation. Advanced ball bearings, on the other hand, use very small and light shafts. The light weight of these units can reduce lag times and increase acceleration.

Limitations

There are two primary limitations to a turbocharger's efficiency: turbo lag and boost threshold. Both of these affect a turbocharger at low speeds, and can be reduced with particular turbocharger designs.

Turbo Lag

Turbo lag results from the slow activation of a turbocharger at low speeds. As the vehicle accelerates, turbochargers can kick in suddenly, resulting in a movement that can be jarring for its passengers. One solution to turbo lag is to make the turbocharger smaller and lighter. Small units are activated more quickly, which increases acceleration and diminishes turbo lag. However, they are less effective at high levels of exhaust flow, and consequently reduce top speed. Some small turbochargers can even spin too quickly, and may become damaged at high speeds. If a small turbocharger is chosen, look for one that has a wastegate to let excess exhaust bypass the turbine altogether.

Boost Threshold

Boost threshold is the lowest amount of exhaust flow needed to propel the turbines. Any amount of exhaust below the boost threshold is insufficient to create compression, which means the turbocharger is inactive. Lowering the boost threshold improves the usefulness of the turbocharger. Most methods used to accomplish this involve adding electrical components to the turbo. For example, an electric compressor is able to activate the turbo boost before there is sufficient exhaust flow for the turbines.

Special Types of Turbochargers

There are two types of turbochargers that can be especially effective at reducing turbo lag and boost threshold. Consider sequential turbochargers and twinchargers for increased efficiency.

Sequential Turbochargers

Standard turbochargers have only a single turbo, which is activated at higher speeds. Sequential turbochargers add a second, smaller unit that can activate the compressor more quickly, allowing the turbocharger to be active across a greater range of speeds. The small unit activates during acceleration, and lets the larger one take over as the vehicle gains speed. This significantly cuts down on the impact of turbo lag.

Twinchargers

Turbochargers are more efficient than superchargers, as they do not draw horsepower from the engine. However, they are less effective at low speeds, as they require high exhaust flow to be powered properly. Superchargers, because they rely on mechanical motion from the engine, are activated immediately. A type of hybrid unit can be purchased, called a twincharger. These highly efficient chargers utilise the best aspects of turbochargers and superchargers to create a powerful and responsive unit.

How to Buy Turbochargers on eBay

Turbochargers and their parts can be purchased from the sellers on eBay. Begin shopping for these products by entering keywords into the search field on the home page. For example, to see listings for all items related to turbochargers, simply enter "turbocharger" into the field. Additional terms, such as a manufacturer name, can be added at any time to continue refining the search. You may also use eBay's category links to shop for turbochargers. These can be found on the home page and in search results. Begin by selecting item types, and use links on subsequent pages to browse listings by vehicle make and model, turbocharger condition, price, and other options.

Click on an item in search results to see its full listing. Be clear on the price of the turbocharger, and remember to add shipping charges to the final cost. It is also worth looking for the seller's shipping methods. In some cases, a full turbocharger may only be available for local pickup. In this case, determine the seller's location, and be prepared to collect the item with your own vehicle or arrange other shipping options before committing to a purchase. Examine all available photos of the item, and compare them with the seller's description. Information about the product from the manufacturer may also be provided.

Research sellers to find experienced and reliable eBay users. Look for sellers with a high positive feedback rating and several completed transactions. Once you have received your purchase, leave feedback of your own to inform the eBay marketplace about your experience.

Conclusion

Turbochargers are one of the most powerful aftermarket additions to a vehicle. They are driven by exhaust from the engine, and force compressed air back into the engine for increased horsepower. Turbochargers can increase engine power by as much as 50 per cent. There are several things for buyers of turbochargers to consider while they shop, including the materials and design of a turbo. Small, lightweight units are designed to be more responsive during acceleration, though they are less effective than larger turbos at high speeds. Some powerful turbos are created with lightweight components, especially the turbine blades, to improve responsiveness at low speeds.

The two primary difficulties with turbochargers are turbo lag and boost threshold. Both affect performance at low speeds. Turbo lag occurs when the turbine blades reach a speed high enough to activate the turbo, which results in a sudden kick to the vehicle's movement. Boost threshold is a related concern, and indicates the lowest amount of exhaust needed to power the turbo. Buyers can choose between two types of specially designed turbochargers to reduce these limitations. The first is a sequential turbocharger, which is built with the addition of a small turbo. This is activated with little exhaust flow, and allows the larger turbo to take over at high speeds. A twin charger combines a turbocharger with a supercharger, and utilises the best aspects of each.

Turbochargers are available from specialty auto parts retailers, as well as online sellers. Marketplaces like eBay have numerous listings for turbos and their parts, and can be used to browse a broad selection of items. Consider all types of turbos to choose a product that can improve a vehicle's performance.

Have something to share, create your own guide... Write a guide
Explore more guides