Throttles

What is the throttle in the car used for?

The car throttle is an essential part of the spark ignition engine hardware, without it driving would not be possible. It is also a basic component of the intake system, and performs a very important function, being responsible for regulating the amount of air supplied to the combustion chamber. Connected to the accelerator pedal by a metal cable and a spring, it is its depression by the driver that controls the opening increasing the opening and supplying more oxygen to the intake manifold. When the vehicle is idling and the accelerator is not depressed, the flap in the throttle is closed. Depending on the design of the actuator and mode of operation, they are divided into electronic and mechanical. In the case of the mechanical variant, a cable and a spring are responsible for the movement of the shaft, which rotates the butterfly mechanism and regulates the opening of the orifice. In the case of electronic with a gas potentiometer, and the opening itself is caused by a stepper motor and controlled by a position sensor.

Does the throttle affect engine power? What are the symptoms of failure?

The premise of tuning a car is to improve its performance and improve parameters such as power and torque of the drive unit. In order to increase engine power, it is necessary to supply more air and fuel, so that the process can be more efficient and generate more energy. A key aspect is to improve the flow of fresh mixture into the engine compartment. The throttle is responsible for dosing the amount of air delivered to the intake manifold, which is why it is such an important aspect of tuning, too small a diameter can prove to be a bottleneck that leads to a decrease in flow, thus reducing engine performance. Mounting a more efficient turbocharger, tuning intake manifolds or even a sport intake will not work if it turns out that the serial throttle is not efficient enough to cope with the higher flow.

FMIC tuning intake throttles

Our offer includes tuning universal throttles, which are used in many intake systems of tuned cars such as Nissan, Toyota, Lexus, Mazda, VW, Skoda, Audi, BMW, Alfa Romeo, Cupra, Honda, Fiat, Kia, Mercedes, Porsche, Mini Cooper, Opel, Subaru, Saab, Seat, Hyundai, Ford, Renault, Volvo, Chevrolet, Mitsubishi and many others. Improved performance is guaranteed by perfectly-fitted components and precise steering to ensure immediate gas response and smooth operation thanks to the bearings. They also feature locking free speed control and a thick aluminum flange welded or bolted to the intake manifold. Larger diameters compared to stock make them widely used in motorsport - often used in streeet, drift, drag, etc. We have JRSpec and FMIC brand universal throttles in diameters from 65 to 100mm. Replacing the throttle with a more efficient one is a relatively low cost that can have very noticeable effects, increasing the amount of air delivered and thus the ability to deliver more fuel that goes to the engine significantly increase power. FMIC PRO throttles are available in kits with intake manifolds and have diameters up to 102 mm. The increased diameter and unimpeded flow in relation to the original allows to fully exploit the potential of the intake manifold and significantly affect the amount of air supplied, and thus the power generated by the engine.

Throttle design

Mechanical throttles are characterized by a simple design, They consist of a housing, and the body itself inside has a cylindrical shape, in its cross-section there is a butterfly valve, which tilts to regulate the amount of mixture by means of a metal cable that is connected to a potentiometer. In electronic communication is carried out by means of a potentiometer and a stepper motor, a very important element of newer designs is the throttle position sensor, the signal generated by it is the basic information for the engine controller about the appropriate amount of fuel.

What are the symptoms of failure? What components should be repaired?

The symptoms of failure are mainly uneven engine operation, jerking during acceleration, dimming of the engine during idling, or slow response to an attempt to accelerate. The consequence of failure can be the immobilization of the car, and fuel consumption may also increase. The basic factor to ensure trouble-free operation is to take care of cleanliness in the intake system. Dirt that can lead to wear of the axles affects the clearances and uneven operation, an important element is also the gasket connecting the manifold to the throttle. Uneven operation is a sign of a dirty stepper motor. A good habit is periodic service and maintenance involving cleaning the assembly, check and clean the throttle and steel cable armor. All you need is a brush and the right chemistry, after spraying it dissolves the carbon build-up which should be collected with a soft cloth. Such maintenance will ensure that the collected carbon build-up will be removed, and the throttle will again work properly thus closing and opening smoothly. It is also necessary to periodically check by hand the clearance, bearing parts, rotation knob and butterfly mechanism clearances. Repair is often costly, it is not possible through the closed structure, a cheaper solution is to replace it with a new one.