UMI’s Stage 3.5 kit is designed to transform your GM A-Body from a comfortable cruiser to a capable corner carver with the twist of the shock. UMI’s lowering springs form the handling foundation and are controlled by Koni off-car rebound adjustable shocks. Our ultra-premium springs feature carefully tuned rates and high quality construction to eliminate the floating feeling and will tie your A-body directly to the road. UMI a-arms feature tubular construction, Delrin bushings for precise steering and caster corrected uppers. The ½” taller upper ball joints work with the lowering springs to tune up the poor factory A-body camber curve. Out back the UMI trailing arms feature Roto-joints for smooth articulation combined with poly bushings for a smooth ride. Adjustable uppers allow for pinion angle tuning while the axle mounted pro-tour bar performs on the street, during cornering and even the occasional dragstrip blast. The entire package is designed and manufactured by UMI in Philipsburg, PA – USA of US materials and we’re proud to drive on and race what we build.
Installation notes: SBC, Pontiac 400 or BBC with aluminum heads and intake tend to sit level with this kit. Lightweight LS may require spring trimming. An additional 1/4″ drop may occur on vehicles with all cast iron full weight big block engines or power adders.
- Increased spindle height by 1/2” via tall upper ball joints for improved camber gain and a better tire contact patch. Works nicely in conjunction with lowering springs.
- Upper a-arms add caster for improved steering feel and straight line stability.
- Lower a-arms feature UMI-built Delrin bushings, premium ball joints and bump stops.
- 1-1/4” front sway bar for flat cornering, CNC bent from 4140.
- UMI 1″ lowering springs feature ultra premium CrSi material with linear rates front and rear for consistent handling. (530 lb/in front, 130 lb/in rear).
- Koni off-car rebound adjustable shocks.
- Rear trailing arms feature Poly and Roto-Joints as well as adjustable uppers for setting pinion angle and rear lateral location.
- Roto-Joints allow smooth articulation for improved handling and less bind.
- 1” diameter rear Pro-Tour sway bar offers tune-able rear roll resistance and less binding for street, corner carving or light drag and is balanced well with our 1-1/4” front bar and spring rates.
- Made in USA.