If you’re planning a B-Body LS swap, choose an LS swap kit that provides solid mounting, proper clearance, and reliable hardware. This guide highlights five practical kits tailored for 1977–1990 B-Body Chevys and related models. The selections balance durability, ease of installation, and adjustable features, helping you pick the right kit for your build. The top buyers are looking for sturdy crossmembers, adjustable mounts, and compatibility with big-block platforms while maintaining driveline angles and A/C/brake clearances.
Summary table of selected products:
- ALMULOO LS Engine Swap Mount and Crossmember Kit — Caprice B-Body (1977–1990). Best for a complete, integrated swap with good clearance.
- maXpeedingrods LS Engine Swap Mount Adapter Kit — G-Body (Monte Carlo, 1973–1988). Best for adjustable positioning and forward/backward engine movement.
- KUAFU Engine Swap Mount Crossmember Kit — Caprice B-Body (1977–1990). Best for strong dual-material construction and added support.
- Yoursme LS Motor Mount Adapter Plates — Universal small-block to LS conversion. Best for versatile fitment.
- LOSTAR LS Conversion Engine Swap Bracket — 1973–1999 GM trucks and B/G bodies. Best for broad compatibility and adjustable setbacks.
ALMULOO LS Engine Swap Mount and Crossmember Kit
Overview: This all-in-one kit is designed to fit 1977–1990 Caprice/Caprice B-body vehicles. It uses a combination of steel and aluminum, offering durability with a lighter weight. The black powder-coated finish resists rust and wear, extending the kit’s lifespan.
Best for: Builders seeking a cohesive swap solution with stable mounting and adequate clearance for A/C and brakes. It helps maintain driveline angles for smoother power transmission.
Why chosen: The kit covers mounting, crossmember support, and alignment considerations in one package, reducing separate part sourcing. It suits buyers prioritizing rust resistance and long-term durability.
Caution: Verify fitment with your exact engine and accessory layout, as high-demand LS setups can vary in A/C and exhaust clearances.
LS Swap Retrofit Engine Aluminum Oil Pan Kit
Overview: This aluminum oil pan kit is designed for a wide range of GM LS1/LS2/LS3 engines within 1955–1987 chassis applications and rear-sump configurations. It emphasizes lightweight construction and maximum chassis clearance.
Best for: Builders needing improved oil pan clearance and a lightweight component to reduce chassis interference during a swap.
Why chosen: Aluminum construction reduces weight while maintaining strength and heat dissipation benefits, helping engine positioning without overloading the front of the vehicle.
Caution: Some rear-dipstick and dipstick compatibility notes apply; check that your oil filter and dipstick setup align with the pan you select.
KUAFU Engine Swap Mount Crossmember Kit
Overview: KUAFU’s kit is specifically designed for the 1977–1990 Caprice B-body, combining steel and aluminum with a powder-coated finish for durability and wear resistance.
Best for: Buyers needing extra structural support when a heavier or more powerful LS engine is installed, ensuring stable mounting and crossmember strength.
Why chosen: The mixed-material construction balances strength and weight, while the powder coating helps protect against rust in harsher climates.
Caution: Ensure the kit’s mounting points align with your chosen engine accessories and engine bay dimensions to avoid fitment issues.
maXpeedingrods LS Engine Swap Mount Adapter Kit
Overview: This adapter kit targets the G-Body family (like Monte Carlo) from 1973–1988, with adjustable mounts that slide to accommodate engine placement in the engine compartment.
Best for: Builders needing precise engine positioning, allowing up to 1/2 inch forward and 1 inch rearward adjustment to clear firewall or tunnel constraints.
Why chosen: The adjustable design helps resolve common fitment issues when installing LS engines in older chassis with tight clearances.
Caution: The kit’s forward/backward offsets may affect driveline angles; plan alignment accordingly to avoid driveshaft binding or exhaust interference.
Yoursme LS Motor Mount Adapter Plates
Overview: This universal adapter set is designed to bolt an LS engine into vehicles originally built with a small-block Chevy, providing OEM-style fitment.
Best for: Builders seeking a versatile adapter solution with straightforward installation and a move of the crankshaft centerline by approximately 0.17 inches for improved fitment.
Why chosen: CNC-machined aluminum plates offer precision and durability, making them a reliable option for a broad range of LS swaps.
Caution: The set includes hardware and plates, but verify that your specific vehicle’s mounting points match the included hardware and thread sizes.
YHB Adjustable Conversion Engine Swap Mounts
Overview: These steel adjustable mounts are designed for installing Gen III/IV LS engines into older GM muscle cars and related platforms. They offer significant forward and rear adjustments to engine placement.
Best for: Buyers needing substantial forward (up to 2.5 inches) and rearward (up to 1/2 inch) movement to fit firewall clearance and trans tunnel constraints.
Why chosen: The wide adjustment range helps resolve common clearance issues in diverse chassis layouts, especially when accommodating low-mounted alternators and A/C compressors.
Caution: Rearward adjustability may be limited for certain low-mount alternator or A/C compressor configurations; plan accessory clearance carefully.
Mejiao LS Conversion Adapter Plates
Overview: CNC milled aluminum plates designed to bolt LS engines into vehicles that originally housed small-block Chevys. Aims to move the crankshaft centerline up about 0.17 inches.
Best for: Builders seeking a precise, aluminum adapter with OEM-style fitment and improved LS installation alignment.
Why chosen: The aluminum construction provides good strength-to-weight ratio and consistent tolerances for reliable mounting.
Caution: Ensure fit with your particular small-block mounting configuration and bolt patterns; verify hardware compatibility before ordering.
LOSTAR LS Conversion Engine Swap Bracket
Overview: The LOSTAR bracket set covers a wide range of GM vehicles from 1973–1999, including Blazer, Silverado, Suburban, Tahoe, Yukon, and many full-size cars. It focuses on adjustable mount positions to fit different firewall and tunnel configurations.
Best for: Builds that require broad compatibility across trucks, SUVs, and B-body cars, with emphasis on adjustable setback and fitment flexibility.
Why chosen: Its broad applicability makes it a practical choice for mixed-use or multi-vehicle projects, especially when exact factory mounting points vary by model.
Caution: With broad compatibility, some fitment refinements may be needed for precise engine-to-bay alignment; plan for minor trimming or custom clearancing if required.
Buying Guide: Key Considerations For B-Body LS Swap Kits
Compatibility: Confirm that the kit supports your specific B-Body model year, engine type, and drivetrain configuration. Some kits target Caprice/Impala B-body cars, while others cover G-body or universal applications.
Mounting Strength: Look for steel or steel/aluminum hybrids with powder-coated finishes for rust resistance and long-term durability. Crossmembers should provide stable alignment for driveline angles.
Adjustability: Engine placement adjustments (forward/backward, up/down) help resolve firewall, tunnel, A/C, and exhaust clearance. Adjustable mounts reduce fitment guesswork.
Clearance: Check A/C compressor, alternator, and brake components clearance when selecting a kit. Ensure the oil pan, dipstick, and oil filter locations work with your chosen engine and pan.
Installation Ease: Kits that include pre-drilled holes, matching hardware, and clear instructions save time. Some universal adapters require more fabrication; budget for extra work if needed.
Materials and Weight: Aluminum parts reduce weight but may require careful torqueing and hardware selection. Steel parts offer strength but add weight; balanced choices help performance and handling.
Budget and Availability: Prioritize kits with availability for your build window. Consider whether a kit provides enough parts in one package to minimize sourcing delays.
Future Upgrades: If planning additional engine mods, choose kits with modular components and adjustable features that accommodate higher power or different LS variants.
FAQ
- What is an LS swap kit useful for in a B-Body car? It provides mounting, crossmember support, and alignment parts to install an LS engine into older GM B-Body vehicles with reliable fitment and clearance.
- Do these kits fit all Caprice B-body years? Many kits target a subset like 1977–1990 Caprice/B-body vehicles, but always verify the product listing for your exact year and model.
- Should I choose aluminum or steel components? Aluminum offers lightness and heat dissipation; steel provides extra strength. A mixed approach can balance weight and durability, depending on the specific kit.
- Is engine placement adjustable after installation? Yes, multiple kits offer forward/backward and slight up/down adjustments to resolve clearance issues after mock-up and test fitment.
- Are universal adapter plates reliable for LS swaps? They can work well when matched to factory mounting points, but ensure compatibility with your vehicle’s engine bay dimensions and hardware.
- Do I need to modify the firewall or tunnel? Some setups require minor clearancing for optimal fit; plan for possible small modifications if necessary to achieve ideal alignment.