YHB Engine Mount Combo for Small-Block Chevy (SBC/BBC) — Solid Steel OEM-Fit Direct Replacement

YHB Solid Motor Engine Mount Combo provides a heavy-duty replacement set of two steel motor mounts and two steel chassis pads designed to stop engine movement in high-performance small-block Chevy installations.

Built from thick steel and engineered to fit classic Chevrolet V8 packages, this kit replaces rubber OEM mounts to deliver a firmer, more direct engine-to-frame connection. It’s intended for race, restored, and custom-frame vehicles where minimizing drivetrain play improves throttle response and prevents linkage bind. The set is sized for common small-block Chevrolet families and includes chassis pad geometry to bolt directly into many vintage frames without modification.

How do these solid mounts change engine behavior under load?

Solid-steel mounts eliminate the cushioning and flex of rubber, reducing engine movement when torque spikes occur. That results in less drivetrain lash, fewer alignment shifts, and a more consistent connection between engine and transmission during hard launches or track use.

• Removes excessive fore/aft and roll movement found in soft mounts
• Prevents throttle linkage and shift linkage from binding under torque
• Improves repeatable power delivery and pedal feel in performance driving

Will this kit fit my Chevy, and which engine/transmission combinations are covered?

The motor mounts in this combo are dimensioned to replace GM OEM part number 3990914 and suit most small-block Chevy installations from the late 1950s through early 1970s. The chassis pads match common mounting locations used across multiple Chevrolet models through the 1970s and 1980s.

• Motor mount ear spacing: 2½" inside measurement, 1-11/16" from rear face to bolt center
• Chassis pad mount centers: 2-5/16" x 5-1/16", center height 2", bolt center 1" from frame surface
• Direct replacement fitment for many Camaro, Firebird, Chevelle, Malibu, Nova, Impala, Caprice, Monte Carlo, and El Camino applications

How are these parts installed and when should I expect to need additional modifications?

Installation follows conventional motor and frame mounting procedures: raise and support the engine, remove the stock mounts, then bolt the YHB steel pieces into place. In most OEM-frame applications these are direct replacements, but custom chassis or modified motor locations may require minor alignment checks or shims.

• Bolts to existing mount points using OE-style hardware (verify torque specs)
• Typically no frame cutting or welding required for listed vehicle fits
• Custom builds may need spacing shims or adapter plates for nonstandard motor positions

What are the trade-offs of switching from rubber to solid mounts?

Solid mounts greatly reduce engine movement but transfer more vibration and noise to the chassis. They’re favored in competition and rigid custom frames, while street-driven vehicles seeking comfort may prefer polyurethane or OEM rubber for smoother NVH (noise, vibration, harshness) characteristics.

• Higher vibration and noise transmitted into the cabin compared with rubber
• Superior stability and repeatable alignment for performance use
• Long-lasting steel construction resists compression and deterioration

Who is this for: This YHB solid motor mount combo is intended for builders, restorers, and racers who need a durable, no-flex engine mounting solution for small-block Chevrolet engines. Choose this set when you prioritize drivetrain stability, precise linkage behavior, and robust welded-steel components for vintage Chevy models or custom chassis projects.