Engine swaps involve replacing one engine with a new one. This can be undertaken to replace an engine that has failed with the same model, or to take out the engine that came with the vehicle and upgrade it with a new one. One popular type of engine swap is the LS engine swap, which uses GM-made engines and provides ample opportunity for customization. If you’re wondering “what is an LS engine swap?” here’s what you need to know.
Available LS Engine Swap Customizations
An LS swap uses any engine made by GM. These vary in price and features, with the most affordable typically starting at $500 and providing a good boost in power for the price. More expensive engines, including the LS1, LS3, and LS7 engines, are made for Corvettes and feature small, durable, and light bodies. These engines provide more power as well, making them a worthwhile investment if you’re specifically looking for that feature. No matter which engine you choose, an LS swap will save you money on fuel mileage and provide better drive-ability and reliability for years to come.
To attach these motors, an adapter plate may be necessary. These plates bolt onto the LS engine block, securely bolting the engine to the crossmember. Adjustable and stock location plates, which attach to where the transmission meets the engine, are available depending on your needs. Most cars will require the LS engine to be moved forward due to firewall clearance issues, so carefully measure and plan for these adjustments.
You have several options when it comes to transmissions. The GM TH350, TH400, and 700R automatic transmissions will require a flexplate adapter but are popular for those on a budget. The GM 4L60E is typically recommended for its good performance to price ratio. A wide range of manual transmissions are also available, with the T56 and TR6060 the highest recommended because it easily bolts to any LS engine. Other manual transmissions typically require additional adaptations to safely function.
Wiring & Computer Systems
LS swaps provide three options for engine wiring harnesses: a standalone harness, a custom harness, or rewiring the harness that came with the engine. The last option is the most common, as it is cost effective and can easily be completed by a professional. Though the wiring process may seem straightforward, professional support is highly recommended for this step of your swap.
Gauges help you understand what’s going on inside your car, so choose them carefully. Mechanical gauges can be installed directly into the LS engine block with adapter fittings and can include a factory speedometer or mechanical speedometer, depending on your transmission. Electronic gauges can easily be wired to the LS wiring harness.
The most common approach to fuel systems in LS swaps is to use a C5 Corvette fuel pressure regulator with an electric fuel pump that has the correct flow. If you don’t already have a fuel injection rated fuel line, you will need to add that to ensure the system has consistent pressure. An intake pump with proper baffling is not necessary but is recommended to avoid fuel starvation when you reach low gas tank levels.
Using a carbureted setup in your swap will require the use of a carburetor LS intake manifold, of which there are many options available. Switching to a carb will allow you to remove unnecessary knock sensors and wiring, but since there is no provision for a distributor, you will need a control box to run the ignition system.
Exhaust system options are plentiful, though all of them will require factory pipe lengthening or shortening depending on the car’s current exhaust system. Using headers instead of factory LS manifolds will help you gain top end horsepower and easily wake up the engine, while retaining the manifolds will provide low-end torque and a quieter drive.
The steam tubes at the top of the heads in the engine prevent the heads from overheating. Make sure the tubes connect somewhere that the air can escape safely, typically to the water pump spacers, water pump housing, or radiator. It’s also important to leave them uncapped unless you’ve completely bled off all the air in the coolant system.
Speak To The Custom Auto Body Specialists
Speak to the custom auto body specialists at Rob’s Customs & Restorations for more information about LS engine swaps. Rob’s specializes in restoring classic, antique, and vintage cars in addition to performing a variety of engine swaps for customers in the Northern Virginia area. Contact Rob’s for a consultation of your vehicle to get expert guidance on the best engine swaps and customizations or to make an appointment for the pros at Rob’s to handle all aspects of the engine swap process.