Expert Chevrolet LS Engine Swaps for
Classic Cars in Castro Valley

Nothing beats the look and style of an old-school classic, but dealing with vapor lock, leaky carburetors, and outdated mechanical ignition can ruin the driving experience. The solution? The Chevrolet LS Engine Swap. At Boulevard Auto Repair & Performance, we specialize in breathing modern, fuel-injected life into classic muscle cars, C10 trucks, and hot rods. From 5.3L iron blocks to massive aluminum LS3s, we provide clean, reliable, high-horsepower custom engine swaps for drivers across Castro Valley, San Leandro, and Hayward.
 

Ready to modernize your classic? [Schedule your LS swap consultation] with our master builders today.
 

Wiring & Control: Standalone vs. Integrated Systems

Dropping the engine into the bay is only half the battle; making it run correctly requires deep electrical expertise. We offer two distinct approaches to engine management depending on your specific vehicle:

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• Standalone Control Systems: Perfect for pure, old-school classics (like a '69 Camaro or '72 C10) that have zero modern electronics. We install highly advanced standalone wiring harnesses and ECUs (like Holley Terminator X or GM Performance) that run the engine completely independently of the rest of the car.

• Integrated Systems: If you are swapping an LS into a slightly newer chassis and want your factory dashboard gauges, push-button start, and body control modules (BCM) to function perfectly, we can seamlessly integrate the modern GM ECU into your vehicle’s existing electrical architecture utilizing our [advanced electrical diagnostics] expertise.
   

Transmission Options: Keep It Classic or Upgrade?

When you massively increase your horsepower with an LS swap, you need a drivetrain that can handle the torque. We give you options:
 

• Keep Your Original Transmission: Want to keep your classic 4-speed manual or traditional TH350/TH400 automatic? We can source and install precision-machined adapter plates and custom flexplates to perfectly mate your old-school transmission to the back of the modern LS block.

• Update to a Modern Transmission: To truly modernize how your car drives, we highly recommend upgrading the transmission alongside the engine. We can install modern, electronically controlled automatics (like the 4L60e, 4L80e, or 6L80) or heavy-duty manual gearboxes (like the Tremec T56) to give your classic smooth, low-RPM highway cruising and massive overdrive fuel economy.
   

Seamless Installation with Chassis Swap Kits

The aftermarket support for the LS platform is massive. If your specific vehicle has a commercially available swap kit—such as heavy-duty conversion engine mounts, tubular crossmembers, and custom-fit swap headers—we can expertly install it. We ensure the engine sits perfectly in the bay with proper hood clearance, correct driveline angles, and zero firewall interference.
 

(Note: Dropping an LS into a classic chassis adds a lot of power. We strongly suggest pairing this swap with an [upgraded suspension] and modern disc brakes to keep the vehicle safe!)
 

California Emissions, Legality, and Off-Road Waivers

Living in California means navigating the strictest emissions laws in the country. It is absolutely critical to understand the legalities of an engine swap:
 

• Making It Legal (BAR Certification): To make an LS swap legally drivable on California streets, it must pass a strict Bureau of Automotive Repair (BAR) Referee inspection. This means the donor engine must be the same year or newer than your chassis, and you must retain every single piece of factory emissions equipment from the donor vehicle (catalytic converters, O2 sensors, EVAP canisters).

• Off-Road & Track Use Only: If you choose to source an engine configuration that bypasses emissions equipment, uses long-tube race headers, or utilizes a non-compliant standalone ECU, the vehicle will never pass a California Smog Check. Because we strictly follow state regulations, any non-BAR-compliant swap performed by Boulevard Auto requires the customer to sign a legal Liability Waiver acknowledging that the vehicle is strictly for Off-Road or Sanctioned Track Use Only. We will be completely transparent with you about your legal options before we ever turn a wrench.

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Build your dream car the right way. [Schedule your LS swap consultation] at Boulevard Auto in Castro Valley today.


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