KTM 150 EXC Engine

The Heart of Every Build: Engine Parts Explained

The engine is the most complex and consequential system in any vehicle. Whether you're performing a routine service, refreshing a worn powerplant, or building a high-output racing motor from scratch, the quality of every component you choose directly determines reliability, longevity, and performance. With over 53,000 products spanning everything from internal rotating assemblies to sealing systems and wiring, this catalog covers the full spectrum of engine work.

What's Inside an Engine Parts Catalog?

Modern engine parts break down into several critical systems, each demanding precision engineering and careful selection. Cylinder block components form the foundation of any engine build — this category encompasses engine blocks, pistons, connecting rods, crankshafts, cylinder heads, and the bearings and hardware that hold it all together under extreme heat and pressure. Getting these core components right is non-negotiable; a marginal piston or an out-of-spec rod can end a build before it ever fires up.

The valve train governs how air and fuel enter and exit the combustion chamber, making it central to power output and efficiency. Camshafts, rocker arms, pushrods, valve springs, and lifters all work in concert, and their specifications have an outsized effect on where in the RPM range an engine makes its power. Closely related, the timing system — chains, gears, and tensioners — keeps the valve train in precise synchronization with the rotating assembly.

No engine build is complete without attending to gaskets and sealing systems. Head gaskets, intake manifold gaskets, valve cover gaskets, and rear main seals are the barriers between combustion pressures, coolant passages, and oil galleries. A compromised seal leads to costly failures, making quality sealing components one of the most important investments in any engine project.

For those performing rebuilds or scheduled maintenance, service kits bundle the most commonly replaced components together for convenience and confidence, while wire, cable, and related components round out the engine bay by ensuring ignition systems, sensors, and accessories communicate reliably.

Top Engine Parts Brands

Speedmaster has been designing, engineering, and manufacturing performance and aftermarket engine parts since 1979. What began as a small speed shop building engines for racers has grown into a global operation known for bringing full in-house manufacturing — from CAD design through production tooling — to an exceptionally wide catalog of engine components.

ARP (Automotive Racing Products) pioneered the concept of fasteners engineered specifically for high-performance engines. Founded in 1968 after Gary Holzapfel recognized that fastener failure was a leading cause of engine breakdowns, ARP developed patented processes for manufacturing high-strength fasteners and today supplies hardware to Formula 1, IndyCar, NASCAR, and NHRA teams worldwide.

Cloyes has been the definitive name in engine timing systems since 1921. With over a century of engineering experience, Cloyes is credited as the first to market with innovations like the TRUE Roller timing chain set and the infinitely adjustable Hex-a-Just timing system, and their kits are backed by a limited lifetime warranty.

S&S Cycle is the benchmark brand for high-performance V-twin engine components, with decades of experience developing internal engine parts, complete engines, and performance upgrades for American motorcycles. Their engine components are a first call for builders pushing V-twin power to its limits.

MAHLE is a global Tier-1 OEM supplier that brings its precision manufacturing standards directly to the aftermarket. Known for pistons, rings, bearings, and gaskets that meet or exceed original equipment specifications, MAHLE is a trusted choice for professional rebuilders prioritizing dimensional accuracy and material quality.