Suspension and Components Suspension Kits

UMI PERFORMANCE

UMI Performance 78-88 GM G-Body Handling Kit Stage 4 450lb Springs 1in Drop - Black

$4,929.99

SKU: U01C GBF004-1-B

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Special Order
Ships in 4–6 weeks
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INSTALL DIFFICULTY
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Advanced — 4+ hours

Description

UMI's Stage 4 kit is designed to transform your G-body into a high-performing vehicle with adjustable features for both street driving and racing. This kit includes UMI's upper and lower tubular a-arms with a 1" increased spindle height for improved handling. The adjustable upper a-arms enhance caster for precise steering, while the lower a-arms feature UMI-built Delrin bushings for smooth and accurate steering. The front of the vehicle is equipped with Viking's new front hybrid coilover, which has double adjustable shocks for ride height, compression, and rebound adjustments. Additionally, the kit includes UMI's 1.250” chromoly handling sway bar for better cornering. At the rear, adjustable tubular frame braces stabilize the Poly/Roto combo lower trailing arms and fully adjustable Roto-Joint upper control arms. Rear lowering springs and double adjustable rear shocks offer 361 possible valving combinations for a customizable ride experience. The kit also features a Pro-Tour style rear sway bar for optimal handling. UMI's Stage 4 Kit includes tubular lower and adjustable upper front a-arms, front and rear sway bars, double adjustable Viking shocks, front coilover springs, rear lowering springs, adjustable rear control arms, tubular frame braces, rear end housing bushings, and premium hardware. For substitutions or customization, please contact our sales staff.

Fitment

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Specifications

BrandUMI PERFORMANCE
Part NumberU01C GBF004-1-B

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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