A replacement automobile engine is an
engine
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
or a major part of one that is sold alone, without the other parts required to make a functional car (for example a
drivetrain
A drivetrain (also frequently spelled as drive train or sometimes drive-train) or transmission system, is the group of components that deliver mechanical power from the prime mover to the driven components. In automotive engineering, the driv ...
). These engines are produced either as
aftermarket parts or as reproductions of an engine that has gone out of production.
Use
Replacement engines are used to replace classic car engines that are in poor condition or broken, or to install a more powerful or more fuel efficient 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 (this is most often seen in
Mopar
Mopar (a portmanteau of "motor" and "parts") is an American car parts, service, and customer care division of the former Chrysler Corporation, now owned by Netherlands-based automobile manufacturer Stellantis. It serves as a primary OEM access ...
muscle cars that have the
426 Hemi installed into them).
Aftermarket engines are used in many forms of
motorsport
Motorsport or motor sport are sporting events, competitions and related activities that primarily involve the use of Car, automobiles, motorcycles, motorboats and Aircraft, powered aircraft. For each of these vehicle types, the more specific term ...
. Some
late model
Late Model stock car racing, also known as late model racing and late models, refers to a type of auto racing that involves purpose-built cars simultaneously racing against each other primarily on oval tracks. This type of racing was early-on ...
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 "re-manned," "reconditioned," or "re-engineered")
* Rebuilt engines
* Used engines
* New engines (also known as "
crate engines")
Terminology
*
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 - a new or remanufactured engine, considered to be equivalent to a new engine.
Parts include more than a long block, including intake manifold, and carburetor or fuel injection system, oil pan, valve covers, and perhaps an alternator
Short block

A short block is an
engine
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
sub-assembly comprising the portion of the
cylinder block
In an internal combustion engine, the engine block is the structure that contains the cylinders and other components. The engine block in an early automotive engine consisted of just the cylinder block, to which a separate crankcase was attach ...
below the
head gasket but above the oil pan,
which usually includes the assembled engine block, crankshaft, connecting rods, and pistons with piston rings properly installed.
An in-block cam engine short block includes the
camshaft
A camshaft is a shaft that contains a row of pointed cams in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition syst ...
,
timing gear, and any
balance shaft
Balance shafts are used in piston engines to reduce vibration by cancelling out unbalanced dynamic forces. The counter balance shafts have eccentric weights and rotate in the opposite direction to each other, which generates a net vertical force ...
s.
Overhead cam
An overhead camshaft (OHC) engine is a piston engine in which the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combusti ...
engines don't include those parts. Short block engines became popular after World War II, when mass production led to great consistency between individual engines; before then, most engines were hand-built and had idiosyncratic variations. Short blocks became less popular after the 1970s when
overhead camshaft
An overhead camshaft (OHC) engine is a piston engine in which the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustio ...
(OHC) engines became the norm, as the rational unit of replacement was the long block, which includes the head, camshaft and valve gear.
A short block is the preferred replacement component for a worn-out engine that requires major servicing beyond the capabilities of a local repair garage, when instead a machine shop may be needed. The short block represents the major wear items of an engine: piston rings, and potentially a rebore of the cylinder bores or replacement
liners, together with reground bearings on the crankshaft. Although replacing the rings or
bearing shells was at one time considered typical garage work, the need for a boring or crank grinding machine now exceed the capabilities of a standard automotive repair garage. A short block includes the preassembled set of major parts needed that generally exceed the capability of the garage, in one item.
The third item sometimes requiring machining, the re-cutting of valve seats in the cylinder head, was less frequently needed. Grinding of valves to fit was once a regular garage task, as was light re-cutting with hand tools, when cast iron seats were common. Once steel seat inserts came into use, either as a result of the switch to
unleaded petrol in the 1970s or fitted into high-performance aluminium heads, machining of heads and the replacement of seats became equally commonly required. Aluminium cylinder heads could also be damaged by warping after overheating, often requiring machining to re-flatten them.
A short block has advantages over dismantling the engine and sending the crankshaft and other related automotive parts away for rework. It is usually quicker to obtain, requiring only a single shipment, rather than having to ship parts to and from the machine shop and the interim time spent at the shop to re-machine those parts. The short block would also have been built in a workshop that was hopefully cleaner and more organised for the specialism of engine building.
Short blocks were
OHV engines. Sidevalves were pre-eminent before the short block appeared as a common item, and they also offered little saving by omitting the (simple) head.
Long block

A long block is an
engine
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
sub-assembly that consists of the assembled
short block with
crankshaft
A crankshaft is a mechanical component used in a reciprocating engine, piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating Shaft (mechanical engineering), shaft containing one or more crankpins, ...
,
cylinder head
In a piston engine, the cylinder head sits above the cylinders, forming the roof of the combustion chamber. In sidevalve engines the head is a simple plate of metal containing the spark plugs and possibly heat dissipation fins. In more modern ...
,
camshaft
A camshaft is a shaft that contains a row of pointed cams in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition syst ...
(usually), and
valve train.
[ A long block does not include the fuel system, electrical, intake, and exhaust components, as well as other components. A long block may include the balancer/damper, timing cover, oil pan and valve covers.][
A long block engine replacement typically requires swapping out parts from the original engine to the long block. These parts can include the ]oil pan
An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) and lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsatur ...
, timing cover, valve covers, intake manifold
An inlet manifold or intake manifold (in American English) is the part of an internal combustion engine that supplies the fuel/air mixture to the cylinder (engine), cylinders. The word ''manifold (engineering), manifold'' comes from the Old Eng ...
, emission-control parts, carburetor
A carburetor (also spelled carburettor or carburetter)
is a device used by a gasoline internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the Ventu ...
or fuel injection
Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of a fuel injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines.
All c ...
system, the exhaust manifold(s), alternator
An alternator (or synchronous generator) is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current. For reasons of cost and simplicity, most alternators use a rotating magnetic field wit ...
, starter, power steering
Power steering is a system for reducing a driver's effort to turn a steering wheel of a motor vehicle, by using a power source to assist steering.
Hydraulic or electric actuators add controlled energy to the steering mechanism, so the driver can ...
pump (if any), and air conditioner
Air conditioning, often abbreviated as A/C (US) or air con (UK), is the process of removing heat from an enclosed space to achieve a more comfortable interior temperature, and in some cases, also controlling the humidity of internal air. Air c ...
compressor
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
Many compressors can be staged, that is, the gas is compressed several times in steps o ...
(if any).
Crate engine
Technically, a "crate engine" or "crate motor" is any automobile engine
There are a wide variety of propulsion systems available or potentially available for automobiles and other vehicles. Options included internal combustion engines fueled by petrol, diesel, propane, or natural gas; hybrid vehicles, plug-in hybr ...
that is shipped to the installer in a crate
A crate is a large shipping container, often made of wood, typically used to transport or store large, heavy items. Steel and aluminium crates are also used. Specialized crates were designed for specific products, and were often made to be reus ...
, which can include short or long block configurations. For this article, a crate engine is defined as a fully-assembled engine that includes more than what is typically installed on a long block; the exact configuration will vary by vendor. It is also sometimes known as a "deluxe long block", which usually includes the fuel and intake system, distributor, oil pan, and ignition system. In some cases, exhaust manifold(s) and the water pump are included.[
Crate engines are manufactured by many different companies, but they all share the same characteristics of being complete engines nearly ready to install once removed from the crate. Generally a crate engine still will require additional parts to be fitted, which can range from minor (engine oil dipstick) to major (intake manifold and fuel injection system), depending on the engine package purchased and the targeted vehicle application. This type of engine has various applications including general replacement, ]hot rod
Hot rods are typically American cars that might be old, classic, or modern and that have been rebuilt or modified with large engines optimized for speed and acceleration. One definition is: "a car that's been stripped down, souped up and ma ...
builds, and motorsports competition. Crate engines are often seen as an economical and more reliable solution as opposed to engine overhauls or custom builds. Such engines are built by specialist engine builders, working in clean and well-equipped workshops, rather than general purpose repair garages.
Crate engines may be either brand new, or substantially rebuilt. If rebuilt, they will have been rebuilt to an extent such that they are considered to be of equal quality, reliability and expected lifetime as a new engine.
Applications
Crate engines are well suited in many different vehicle platforms. Engines are often used in the following applications:
* General automobile engine replacement
* Custom hot rod street builds
* Marine engine replacements
* Motorsports Competition (Asphalt, dirt track, drag racing
Drag racing is a type of motor racing in which automobiles or motorcycles compete, usually two at a time, to be first to cross a set finish line. The race follows a short, straight course from a standing start over a measured distance, mos ...
etc.)
Advantages
Crate engines are often seen as an economical choice no matter what the application is. In general automobile engine replacement, a crate engine is often very competitively priced when compared to the cost of a full rebuild of a faulty engine. It is also quicker to ship from stock than to wait an equal time for parts, then to begin a rebuild. Installers often opt for the crate engine because of the cost and ease of replacement. Crate engines are typically a bolt-in replacement with no internal work being performed to the engine compared to a complete overhaul that requires internal part replacement by trained mechanics. Hot Rod and other custom street applications also often choose a crate engine because of the higher value when compared to a custom built engine.
In motorsports, the crate engine option has become very popular for various reasons. Crate engines are often a more affordable option when compared to a purpose-built race engine so budget racers often go this route. The crate engine also has developed a large fan base in many different racing series because of the competitive racing. As all racers in the field have identical engines, the races are won by driver's talent and chassis setup, and not the amount of horsepower a team can afford to build into their engine.
EV crate engines
In general, simply swapping an internal combustion engine for an electric traction motor
A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric vehicle, electric or hydrogen vehicles, or electric multiple unit trains.
Traction (engineering), Traction motors are used in electrically powe ...
is not sufficient; a complete electric vehicle
An electric vehicle (EV) is a motor vehicle whose propulsion is powered fully or mostly by electricity. EVs encompass a wide range of transportation modes, including road vehicle, road and rail vehicles, electric boats and Submersible, submer ...
(EV) drivetrain conversion also requires installation of a storage battery, inverter, reduction gear, and controller. Most of these separate components can be packaged with the motor in a unit that is dimensionally compatible with the existing engine compartment, but the battery is usually the bulkiest, heaviest component of an EV powertrain and can create a significant challenge for fitment.[ In recent years, the restoration and EV conversion of a ]classic car
A classic car is typically described as an automobile 25 years or older, although a car's age is not the only requirement it must meet before being considered a "classic." However, a standard criteria for recognizing cars as classics does not ex ...
has become known as an '' electromod'', a portmanteau
In linguistics, a blend—also known as a blend word, lexical blend, or portmanteau—is a word formed by combining the meanings, and parts of the sounds, of two or more words together. of electrification and restomod
Conservation and restoration of road vehicles is the process of restoring a vehicle back to its original working condition. Vehicles, whether partially scrapped or completely totaled, are typically restored to maintain their roadworthiness or to ...
.
Aftermarket
Hobbyists have been converting cars to EVs since at least the 1960s. Historically, these have used aircraft starter motor
A starter (also self-starter, cranking motor, or starter motor) is a device used to rotate (crank) an internal-combustion engine so as to initiate the engine's operation under its own power. Starters can be electric, pneumatic, or hydraulic. T ...
s and lead-acid batteries; several books have been written to document and guide these conversions, including ''The Complete Book of Electric Vehicles'' (Shacket, 1979), ''How to Convert to an Electric Car'' (Lucas & Riess, 1980), ''Convert It'' (Brown & Prange, 1993), and ''Build Your Own Electric Vehicle'' (Brant, 1994). Many recent non-factory electromods are implemented by extracting and adapting the complete drivetrain (traction motor(s), battery, controller, and inverter) from an existing mass-produced EV, such as Tesla. East Coast Defender demonstrated a Tesla EV-sourced powertrain conversion of a 1969–96 Range Rover Classic
The Range Rover is a Four-wheel drive, 4x4, mid-size off-road vehicle series produced from 1970 to 1996 – initially by the Rover Company, Rover (later Land Rover) division of British Leyland, and latterly by the Rover Group.
The first generat ...
, developed with Electric Classic Cars, to ''Motor Trend
''Motor Trend'' is an American automobile magazine. It first appeared in September 1949, and designated the first Car of the Year, also in 1949.
Petersen Publishing Company in Los Angeles published ''Motor Trend'' until 1998, when it was sold ...
'' in 2021. In October 2019 there were no purpose-built crate engine EV kits available commercially, but such projects were in development. For example, EV West announced their Revolt Tesla Crate Motor in 2020, which married an electric traction motor from Tesla with a gear reduction unit and ended in a universal joint yoke, a suitable interface for a driveshaft. Mechanically, the motor is fitted with mounts compatible with Chevrolet small-block engines to take advantage of numerous small-block repower kits.
Automobile manufacturers
Previously in 2018, Chevrolet Performance
Chevrolet Performance, formerly "GM Performance Parts", is an automotive performance parts brand that sells everything from camshafts and cylinder heads to high-performance crate engines and upgrades for late-model Chevrolet vehicles. It was foun ...
advanced an "electric crate motor" concept with the unveiling of the eCOPO Camaro at that year's SEMA
Sama (; ) is a Sufi ceremony performed as part of the meditation and prayer practice dhikr. Sama means "listening", while dhikr means "remembrance".During, J., and R. Sellheim. "Sama" Encyclopedia of Islam, Second Edition. Ed. P. Bearman, T. B ...
show. The eCOPO Camaro was a 2019 COPO Camaro which was equipped with a pair of BorgWarner
BorgWarner Inc. is an American automotive and Electric vehicle, e-mobility supplier headquartered in Auburn Hills, Michigan. As of 2023, the company maintains production facilities and sites at 92 locations in 24 countries, and generates revenu ...
HVH250-150 motor assemblies instead of the conventional piston engine. The electric traction motor essentially served as a drop-in replacement with the same bellhousing bolt pattern and crankshaft flange as the LS engine family, so the car retained the same transmission, driveshaft, and axles as the conventional COPO Camaro. At the 2019 SEMA show, Chevrolet continued to develop the concept, following up with the E-10 Concept, which used the powertrains from two Bolts repackaged into in a restored 1962 C-10 pickup truck. The following year for SEMA, Chevrolet showcased the "Electric Connect and Cruise" eCrate package in October 2020, which included the main drivetrain components of a single Bolt (motor, battery, controller, and inverter), and was demonstrated as a retrofit to a restored 1977 K5 Blazer. The kit was scheduled to go on sale in the second half of 2021. The Bolt motor is modified by removing the differential and reduction gear unit, then fitting an adapter plate and crank flange, allowing it to bolt to a conventional transmission. Together with the controller and inverter, the motor occupies approximately the same space as a small-block V8; the battery presents a greater challenge for packaging, which is why the initial development has focused on trucks. , it was still being explored as a "future business opportunity", according to Chevrolet Vice President Scott Bell.
In November 2021, Ford Performance
Ford Performance (formerly Ford Racing) is the high-performance division of the Ford Motor Company and the multinational name used for its motorsport and racing activity.
History
* 1896 – Henry Ford reached a top speed of 20 mph in his ...
released the "Eluminator" crate EV motor, which was the same traction motor used in the Ford Mustang Mach-E
The Ford Mustang Mach-E is a Battery electric vehicle, battery electric compact crossover SUV produced by Ford Motor Company, Ford. Introduced on November 17, 2019, it went on sale in December 2020 as a 2021 model. The Mach-E is part of the F ...
GT Performance Edition and used to power the 1978 F-100 Eluminator restomod pickup truck. As of 3 November 2021, it was available for pre-order but not yet shipping.
Common crate engines used in North American racing
General Motors began developing several small block crate race car engines in 2001 and they were released into production in 2002. The engines are sealed and repairs being done by certified rebuilders.
Chevrolet 602
The Chevrolet engine debuted in 2002 with part number 1958602 and sold for a little under $4000 in 2012. It has 350 cubic inch displacement via a 4.000 inch bore and 3.480 inch stroke. The 602 engine is equipped with iron heads, a cast-iron block, and aluminum pistons. It produces about 350 horsepower and 390 foot-pounds of torque at 9.1:1 compression.
Applications for this engine include: IMCA Hobby Stock, IMCA Northern Sport Modified, IMCA Southern Sport Modified, Mid-American Stock cars. Northeastern (United States) Sportman, Crate Racing USA, and others.
Chevrolet 603
The Chevrolet engine has part number 88959603. It has 355 cubic inch displacement and 405 foot pounds of torque at 10.1:1 compression. The 603 engine is equipped with aluminum heads, steel crank, and high silicon pistons. The American Canadian Tour
The American-Canadian Tour (ACT) is an independent regional stock car racing series based in the northeastern United States, and Eastern Canada. The American-Canadian Tour was founded in 1979 and conducts professionally-run stock car racing event ...
(ACT) late model sportsman utilize this engine.
Chevrolet 604
The Chevrolet engine debuted in 2002 with part number 88958604 and sold for about $5000 in 2012. The 604 engine is equipped with aluminum heads, forged steel crankshaft, and an aluminum intake. It produces about 400 horsepower and 400 foot-pounds of torque with a 9.6:1 compression.
Applications for this engine includes IMCA Modifieds (starting in 2013), CRA All Stars Tour (allowed but not required), United Crate Racing Alliance, Big 8 Series, RUSH Late Models, Crate Racing USA, and others.
Ford 347
Ford Performance 347 Cubic Inches 415 HP Sealed Racing Engine
Replacement blocks
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
Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...
instead of original iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...
, or in stronger alloys. Often they imitate the larger available displacements that were produced in small numbers or allow for displacements never available.
See also
*Engine tuning
Engine tuning is the adjustment or modification of the internal combustion engine or Engine Control Unit (ECU) to yield optimal performance and increase the engine's power output, economy, or durability. These goals may be mutually exclusive; ...
* Engine swap
*Engine configuration
The engine configuration describes the fundamental operating principles by which internal combustion engines are categorized.
Piston engines are often categorized by their cylinder layout, valves and camshafts. Wankel engines are often categoriz ...
References
{{reflist
External links
GM crate engines
Ford crate engines
Most common types of replacement engines
Complete Crate Engines-Auto Parts USA
Automobile engines