The camshaft of your vehicle is one of the most important components of your engine system. The cam and lifter, specifically, perform a tandem function in order to provide the appropriate mixture of air and fuel into the internal combustion engine. Although you may not know the technical significance of high-performing cams and lifters, you have to make sure that your car has the right type of these components. There is no need to be shy to ask your mechanic about what these parts do. Read on and find out for yourself.
Types of cam according to shape
- Roller cam ? this type has a more efficient design. A roller cam has a round lobe that is almost similar at the top and base, and this rounder lobe reduces friction against the cam lobe and the follower. As a result, a roller cam increases rpm potential and produces higher valve spring pressures. This type is used in cars manufactured from the mid-1980s onwards.
- Flat tappet cam - this type looks like an egg with a flatter flank on each side and a round base. This type can only withstand a certain amount of valve spring pressure, so excess pressure causes damage to the cam lobe and the face of the follower. The flat tappet cam is less expensive and simpler when it comes to operation, but it may not be able to adapt to various oil compositions.
Types of lifter according to performance
- Solid ? this type allows the engine to produce more rpm, the reason it is used in race cars. Also called a mechanical lifter, this type has a stationary plunger where the push rod sits in. The only downside is maintenance requirements, because you have to lash the valves, which means that you must put clearance between the cam lobe and valve stem. A solid lifter must experience short idle time because it needs high oiling at all times.
- Hydraulic ? this type has a movable plunger controlled by internal valves where pressurized oil flows through. It requires a preload when the valve is closed; preload is the distance between the retaining snap ring and the plunger seat. The problem with a hydraulic lifter is that valve train and lifter timing is less efficient at higher rpm. If you are a common driver, you may opt for this type because it only needs less maintenance.
- Make sure that you buy your cam and lifter from the same auto parts store. The cam and lifter are made from solid metal that has a specific strength; if the metal strength of the two parts is not identical, one will put dent or eat up the metal surface of the other.
- Make sure that you choose a cam with a smaller grind and smaller size for better performance. Do not forget to ask your professional engine builder about the type applicable to your driving needs.