Replacement engines are used to replace classic car engines that are in poor condition or broken, or to install a more powerful engine in a vehicle. Replacement engines are often used to make old cars more reliable for daily driving. Classic car hobbyists may also install reproductions of a rare powerplant in a classic car.
Aftermarket engines are used in many forms of motorsport. Some late model racecar series use “crate engines” many of which are made by independent firms. This ensures that drivers all have similarly powered racecars. Legends and Allison Legacy Series cars also use sealed crate motors.
Types of replacement engines
The four most common types of replacement engines are:
- Remanufactured engines (also known as “reconditioned” or “re-engineered”)
- Rebuilt engines
- Used engines
- New engines (also known as “crate engines”)
New castings of some engines are sometimes produced by independent companies. These blocks commonly replace rare or popular designs for aftermarket rebuilding, especially when the original is no longer produced. They are sometimes available in aluminum instead of original iron, or in stronger alloys. Often they imitate the larger available displacements that were produced in small numbers or allow for displacements never available.
- “Short block” – everything between the cylinder head and the oil pan (excluding those items)
- “Long block” – a short block, with mounted and gasketed cylinder head, valves and camshaft
- “Crate engine” – often more than a long block, including intake manifold, and carburetor or fuel injection system, and perhaps an alternator