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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Description

Part #: GBF004-1-B

Who says you can't have it all UMI's Stage 4 kit transforms your G-Body into a handling machine with the adjustability to perform well at the strip or haul your family comfortably - to the autocross. If drag racing is more your style, a few minor changes at initial purchase (or down the road) will have you launching with the best of them, then canyon carving on the way home! Up front we start with UMI's proven upper and lower tubular a-arms loaded with " taller upper and lower ball joints giving you a total of 1" increased spindle height. The adjustable upper a-arms increase caster, without additional shims, for a precise steering feel. The lower a-arms are loaded with UMI-built Delrin bushings for smooth non-binding motion and precise steering. Viking's new front hybrid coilover with double adjustable shock allows ride height, compression and rebound adjustment. The ride height adjustment is accomplished with the included spanner wrenches and thrust washers. The compression and rebound adjusters are clicked by hand (no tools!) and feature a total of 361 possible valving combinations. The front is completed by UMI's 1.250" CrMo handling sway bar. Out back we stiffen the chassis with adjustable tubular frame braces which stabilize the Poly/Roto combo lower trailing arms and fully adjustable Roto-Joint upper control arms. 1" or 2" lowering rear springs are controlled by Viking's double adjustable rear shocks, once again featuring 361 possible combinations. Rounding out the rear is our Pro-Tour style rear sway bar. This 3-way adjustable bar features 1" tubular construction, race style end links and UMI's proven CNC machined clamping system. One bar allows street, road race, auto-x and drag settings. As always, this kit features UMI's quality red or black powder coat and premium hardware. All UMI components are manufactured with pride in Philipsburg, PA - USA.

MIA's 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.

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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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