Engine swaps into classic GM trucks and muscle cars rely on precise mounting hardware. The following LS swap motor mount kits are designed to adapt LS engines (LS1, LS2, LS3, and more) to various small-block Chevy frames, delivering alignment accuracy, sturdy construction, and flexible installation options. This guide compares five popular kits, highlighting compatibility, installation features, and overall value to help you choose the right mounting solution for your project.
| Product | Vehicle Fit | Key Benefit |
|---|---|---|
| LS Swap Motor Mounts Adapter Plates – Universal Swap Bracket | Small block Chevy to LS engine | Billet aluminum, up .17″ crankline adjustment |
| LS Swap Motor Mounts for 1973-1998 Square Body | OBS/C/K trucks, 4WD & 2WD | Wide compatibility with transmissions |
| LS Swap Motor Mount Brackets for 1973-1998 C/K | Chevy/GMC 2WD/4WD trucks | 2″ forward, 1/2″ back adjustable mounting |
| Universal LS Conversion Adapter Plates | LS engines to small-block frames | CNC machined aluminum, precise fit |
| maXpeedingrods LS Engine Swap Mount Kit for G-Body | 1973-1988 G-Body (Monte Carlo, etc.) | Includes hardware, multiple LS engine options |
Universal Small Block to LS Adapter Plates
The adapter plates are designed to bolt an LS series engine into vehicles that originally housed a small block Chevy engine, simplifying compatibility with existing mounts. The plates are machined to OEM specifications to ensure a precise fit, and they shift the crankshaft centerline by approximately 0.17 inches to optimize alignment within the chassis. The package includes two adapter plates with eight flat-head bolts and six flange M10-1.5 bolts, making assembly straightforward for a range of LS configurations, including LS1, LS2, LS3, LS6, LS7 and traversal options such as LQ4, LQ9, L92, L99, L33, and LR4. For builders aiming to minimize modification while maintaining alignment accuracy, this kit offers a solid foundation with durable billet aluminum construction.
LS Swap Mounts for 1973-1998 Square Body Trucks
This LS engine swap mount set is slotted for easy adjustment of engine placement, enabling precise installation within the engine bay. The mounts support a broad range of transmissions, including 4L60E, 4L65E, TH350, TH400, TH700R4, and other standard or automatic configurations. Compatibility spans the LS1 through LS9 line (1997-2014) and Vortec truck engines (1999-2013), covering a wide array of 4.8L, 5.3L, 6.0L, and 6.2L variants. The kit is suitable for 1973-1998 OBS and Square Body Chevrolet/GMC trucks, including 2WD/4WD C10, C/K, Blazer, and Tahoe models. The adjustable design helps tune engine position relative to the transmission and crossmember, supporting better drive-line alignment and drivetrain geometry in a classic body style.
LSO Moun t Brackets for Classic Chevy/GMC
Designed for 1973-1998 Chevy/GMC trucks, these brackets provide compatibility with LS1 through LS9 engines as well as common truck variants (4.8L-6.2L). The brackets are adjustable, enabling 2 inches of forward placement and 1/2 inch of rearward placement, which is particularly helpful when balancing clearance with headers, steering components, and exhaust routing. The kit aims to simplify installation and improve engine placement accuracy for reliable driveline alignment across a broad range of body styles. It is a practical option for builders seeking adjustable mounting without extensive fabrication.
Universal LS Conversion Adapter Plates Kit
These CNC milled aluminum adapter plates are crafted to deliver high-precision alignment for LS engine installations into vintage frames originally fitted with a small-block Chevy. The plates are designed to move the crankshaft centerline up by 0.17 inches, which can improve drivetrain geometry and power delivery characteristics. The machining quality aims to provide a snug, rigid fit that minimizes flex and vibration. The kit is suitable for a wide range of LS engines including LS1, LS2, LS3, LS6, LSX, and related variants like LQ4, LQ9, L92, L99, L33, and LR4, making it a versatile choice for many swap projects seeking a clean, bolt-on approach.
maXpeedingrods LS Engine Swap Mount Kit
This LS engine swap mount kit is designed for G-Body cars produced between 1973 and 1988, including Monte Carlo and other GM platforms. It accommodates LS1, LS2, LS3, LS6, LSX, and related engine variants such as LQ4 and LQ9, as well as 4.8L-6.2L Vortec configurations. The set includes hardware and spacers with a powder-coated finish for corrosion resistance, and it emphasizes straightforward installation with durable, powder-coated components. This kit is positioned as a practical option for users seeking a robust mounting solution with included hardware for a reliable swap experience in classic G-Body applications.
Buying Guide
- Engine compatibility: Verify which LS variants (LS1, LS2, LS3, LS6, LS7, LS9, LQ4, LQ9, L92, L99, L33) are supported by each kit and whether your small-block Chevy frame is compatible with the adapter plates.
- Adjustability: Look for adjustable brackets or plates that allow forward/backward, up/down movement, and crankline alignment to fit transmission and exhaust clearance, steering linkage, and crossmembers.
- Material and finish: Billet aluminum or CNC-machined aluminum offers rigidity and durability; powder coating adds corrosion resistance for street or track use.
- Transmission compatibility: Ensure the mounts support the intended transmission family (TH350/TH400, 4L60E/4L65E, etc.) and that the overall fit accommodates the chosen gearbox.
- Installation complexity: Some kits are more plug-and-play with existing hardware; others may require additional fabrication. Consider your experience level and tool access.
- Clearance and geometry: Proper engine placement improves driveline angles, exhaust routing, and steering clearance. An adjustable setup can help optimize performance and reduce vibrations.
- Hardware inclusions: Check whether the kit includes all necessary bolts, spacers, and brackets, so you won’t need to source parts separately.
- Warranty and support: Confirm the manufacturer’s warranty and access to support if you encounter fitment questions during installation.
When choosing between these options, consider your vehicle type (classic truck vs. muscle car), desired engine position, and the level of fabrication you’re ready to undertake. A higher-precision, CNC-machined adapter will typically offer the most reliable fit, but may come at a higher upfront cost. Conversely, more universal brackets can save time if your project has multiple mounting constraints or unusual crossmembers. The right kit will balance engine fit, transmission compatibility, and overall driveline geometry to deliver a solid, long-lasting LS swap.