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High-load Condition

Those instances when the air conditioner must operate continuously, at maximum capacity, to provide the cool air required.

High-mounted Coil Spring Suspension

A type of suspension having a coil spring located above the upper control arm, with the top end of the spring contacting the car body inside a spring tower.

High-performance Speed Rating

A rating system used for tires designed for high-performance cars such as SR, HR, and VR.

High-performance Tire

A tire having a high-performance speed rating, such as SR, HR, or VR.

High-performance Tire

A tire with serious traction capabilities, usually for both straight-line acceleration and cornering performance. Many high-performance tires feature a soft rubber tread compound, which enhances traction but can shorten the tire's lifespan. Of course, people who are in search of optimum traction usually are willing to sacrifice a bit of tire longevity, as well as some performance in rain and snow.

High-pressure Control

A term used for high-pressure cut off switch.

High-pressure Cutoff Switch

An electrical switch activated by a predetermined high pressure to open a circuit during certain high-pressure periods.

High-pressure Line

1. The lines or hoses from the compressor outlet to the metering device inlet of an air conditioner. 2. Any line or hose that carries high-pressure liquid or gas, such as a power-steering hose.

High-pressure Relief Valve

A mechanical device designed so that it releases the extreme high pressures of the system to the atmosphere.

High-pressure Side

1. That part of an air-conditioning system, from the compressor outlet to the evaporator inlet, that is under high pressure. 2. Any part of a system, such as fuel injection, that is under high pressure.

High-pressure Switch

An electrical switch activated by a predetermined high pressure.

High-pressure Vapor Line

A line or hose running from the compressor outlet to the condenser inlet.

High-rise

The tallest style of truck cap. Also called a high-top. This design provides the most head room, which is important if you're tall, if you plan to camp inside the shell or if you expect to spend a lot of time loading and unloading cargo.

High-side Pressure

A term used for discharge pressure.

High-side Service Valve

A device located on the discharge side of the compressor, permitting the service technician to check the high-side pressures and perform other necessary operations.

High-speed Steel (HSS)

An extremely hard alloy.

High-speed System

A carburetor main-metering system that supplies fuel to the engine at speeds above 25 mph (40 km/h).

High-swirl Combustion (HSC)

Ford's name for a cylinder head and valve design that promotes turbulence in the combustion chamber during the power stroke, contributing to complete and efficient burning of the air/fuel charge.

High-swirl Port Technology

A cylinder-head design with high-speed air flow to pack more air/fuel mixture into the combustion chamber.

High-temperature Coating

A ceramic or other coating for a metal product, typically a header or a complete exhaust system, that provides rust protection, helps it withstand high temperatures and helps keep those temperatures contained in the component. For instance, keeping exhaust gas temperatures contained within a header, rather than allowing the heat to pass into the engine compartment, results in improved engine performance. Specialized coatings also can be applied to high-performance pistons and other engine components.