UMI Performance 78-88 GM G-Body SBC Poly Engine Mount Kit - 90071

The UMI Performance 90071 SBC Poly Engine Mount Kit is a direct bolt-on engine mount solution engineered specifically for 1978–1988 GM G-Body vehicles equipped with a small-block Chevy (SBC) engine. Built in the USA and designed with the high-performance street driver in mind, this kit replaces worn or deteriorated factory mounts with a more durable, performance-oriented alternative that keeps your drivetrain planted and properly located under load.

Key Features & Benefits

• Polyurethane Inserts: The poly bushings deliver firmer engine support compared to soft OEM rubber mounts, helping reduce drivetrain slop and improving throttle response feel — without the harshness of a solid mount that can transmit excessive vibration into the cabin.
• 3/16" Mild Steel Construction: The mounts are fabricated from 3/16" mild steel, providing the structural rigidity needed to handle the torque demands of a performance SBC build.
• Black Powder Coat Finish: The powder coat finish offers corrosion resistance and a clean, professional appearance under the hood.
• Direct Bolt-On Fitment: Designed as a direct replacement for the factory mounting location on 1978–1988 G-Body platforms — no cutting, drilling, or fabrication required. A verified buyer noted "fitment was spot on and no shimming required."
• Made in the USA: UMI Performance manufactures this kit domestically, consistent with their broader lineup of American-made suspension and chassis components.
• Sold as a Complete Kit: Includes two engine mounts, giving you everything needed to replace both sides in one order.

Specifications

• Part Number: 90071
• Brand: UMI Performance
• Material: 3/16" mild steel with polyurethane inserts
• Finish: Black powder coat
• Mounting Style: Direct bolt-on
• Quantity: 2 mounts (complete kit)
• Country of Origin: United States
• UPC: 0013102005255

Fitment

This engine mount kit is designed to fit 1978–1988 GM G-Body vehicles with a small-block Chevy (SBC) engine. GM G-Body models in this era include the Chevrolet Malibu, Monte Carlo, El Camino, Buick Regal, Oldsmobile Cutlass Supreme, and Pontiac Grand Prix. Always confirm your specific year, model, and engine combination before ordering — this kit is specifically for SBC applications and is not intended for big-block or LS/LSX engine swaps (UMI offers separate mount kits for those configurations).

What's in the Box

• 2x SBC poly engine mounts (driver and passenger side)

Why Buy from ThreePiece.us

ThreePiece.us ships every order completely free — no minimum required, no hidden fees at checkout. If you'd prefer to spread the cost over time, Affirm financing is available so you can get your G-Body build moving without waiting. Our team understands performance suspension and drivetrain components inside and out, so if you have a fitment question about this UMI mount kit or anything else in your build, we're here to help you get it right the first time.

Frequently Asked Questions

Q: Will these mounts fit my Monte Carlo or El Camino?
A: This kit is designed for the 1978–1988 GM G-Body platform, which includes the Chevrolet Monte Carlo, El Camino, Malibu, Buick Regal, Oldsmobile Cutlass Supreme, and Pontiac Grand Prix — provided the vehicle is equipped with a small-block Chevy engine. Verify your exact year and engine before ordering.

Q: Are these solid mounts, or do they have some vibration dampening?
A: These are polyurethane insert mounts — not solid mounts. The poly bushings are firmer than stock rubber, which reduces drivetrain movement and improves feel under hard acceleration, while still providing a degree of vibration isolation suitable for a street-driven vehicle.

Q: Do I need to modify anything for installation?
A: No. These are direct bolt-on replacements for the factory SBC G-Body mounting location. According to a verified buyer, fitment was spot on with no shimming required.

Q: How many mounts come in the kit?
A: The kit includes two mounts — one for each side — so you have everything you need to complete both engine mount positions in a single purchase.