1975-1981 Camaro Firebird Trans Am Front Upper and Lower A-Arm Mounting Hardware Kit, UMI-2603

Hawks Motorsports is proud to offer our clients this : 1975-1981 Camaro, Firebird, Formula and Trans Am Front Upper and Lower A-Arm Mounting Hardware Kit from UMI Performance.

UMI Performance #2603 supplies the high-grade fasteners needed to mount both front upper A-arms and both front lower A-arms to the subframe of compatible 1975-1981 Chevrolet Camaro and Pontiac Firebird models.

The kit includes zinc-plated high-grade bolts, matching washers and nylon-insert locking nuts for the driver- and passenger-side upper and lower control arms. The zinc-plated finish helps protect the components against corrosion while providing a clean appearance for restored and performance-oriented front suspensions.

UMI-2603 is compatible with applicable UMI Performance front A-arms, original GM upper and lower A-arms, factory-style replacement control arms and compatible aftermarket A-arms using the original mounting arrangement.

This kit is specifically configured with 14mm metric lower A-arm pivot bolts, matching the factory-style lower-control-arm mounting arrangement used on 1975-1981 Camaro and Firebird models. The upper A-arm mounting hardware uses the same basic configuration across the 1970-1981 second-generation F-body platform; the lower A-arm bolt diameter determines whether UMI-2602 or UMI-2603 is correct.

UMI-2603 is an excellent choice when installing new control arms or replacing original fasteners that have become rusted, seized, bent, worn, damaged or lost. It is suitable for factory restorations, front-suspension rebuilds, street-performance vehicles, Pro-Touring builds, autocross cars, road-course vehicles and compatible drag-racing applications.

Complete Kit Contents

• Eight high-grade A-arm mounting bolts
• Four front upper A-arm mounting bolts
• Four 14mm metric front lower A-arm pivot bolts
• Matching washers
• Matching nylon-insert locking nuts
• Zinc-plated finish
• Hardware for both front upper A-arms
• Hardware for both front lower A-arms
• Hardware for the driver- and passenger-side mounting positions

Compatible Front Control Arms

UMI-2603 is designed for:

• Applicable UMI Performance front upper A-arms
• Applicable UMI Performance front lower A-arms
• Original GM front upper A-arms
• Original GM front lower A-arms
• Factory-style replacement upper and lower control arms
• Compatible tubular aftermarket A-arms
• Lower A-arms using factory-style 14mm mounting sleeves
• Compatible rubber-bushed control arms
• Compatible polyurethane-bushed control arms
• Compatible Delrin-bushed control arms
• Control arms designed for factory-style coil springs
• Compatible control arms designed for coilover conversions

Always confirm the lower-control-arm bushing-sleeve diameter and the vehicle’s existing fastener size before ordering.

Selecting the Correct UMI Hardware Kit

• UMI-2601: Front upper A-arm hardware only for applicable 1970-1981 F-body models
• UMI-2602: Front upper and lower A-arm hardware with 1/2-inch lower pivot bolts for 1970-1974 Camaro and Firebird
• UMI-2603: Front upper and lower A-arm hardware with 14mm metric lower pivot bolts for 1975-1981 Camaro and Firebird

UMI-2603 should not be advertised as a universal 1970-1981 F-body hardware kit. The lower A-arm fastener size changed during the second-generation model run.

Important Position Information

UMI-2603 installs at the mounting points where the front upper and lower A-arms attach to the vehicle’s front subframe.

This kit is not:

• Ball-joint mounting hardware
• Upper or lower ball-joint castle nuts
• Shock mounting hardware
• Coil-spring hardware
• Coilover mounting hardware
• Sway-bar frame hardware
• Sway-bar end-link hardware
• Steering-linkage hardware
• Tie-rod hardware
• Subframe-to-body mounting hardware
• Subframe-connector hardware
• Rear leaf-spring hardware
• Rear sway-bar hardware
• Rear axle or differential hardware

4. KEY FEATURES

• Designed for 1975-1981 second-generation GM F-body models
• Fits Chevrolet Camaro applications
• Fits Pontiac Firebird applications
• Fits Pontiac Firebird Esprit applications
• Fits Pontiac Firebird Formula applications
• Fits Pontiac Firebird Trans Am applications
• Fits applicable Turbo Trans Am models
• Services the front upper and lower A-arms
• Mounts the control arms to the front subframe
• Supplies mounting hardware for all four front A-arms
• Includes eight high-grade mounting bolts
• Includes four upper A-arm mounting bolts
• Includes four 14mm metric lower A-arm pivot bolts
• Includes matching washers
• Includes matching nylon-insert locking nuts
• Nylon locking inserts help resist loosening caused by normal vibration
• Zinc-plated finish
• Zinc plating helps resist corrosion
• Provides hardware for the driver and passenger sides
• Compatible with applicable UMI Performance upper A-arms
• Compatible with applicable UMI Performance lower A-arms
• Compatible with original GM upper A-arms
• Compatible with original GM lower A-arms
• Compatible with factory-style replacement control arms
• Compatible with properly sized aftermarket tubular A-arms
• Suitable for compatible rubber-bushed control arms
• Suitable for compatible polyurethane-bushed control arms
• Suitable for compatible Delrin-bushed control arms
• Suitable for factory-style coil-spring applications
• Suitable for compatible coilover control-arm applications
• Direct-fit configuration for verified applications
• Replaces corroded, seized, bent, worn, damaged or missing original fasteners
• Suitable for factory restoration projects
• Suitable for front-suspension rebuilds
• Suitable for street-performance vehicles
• Suitable for Pro-Touring builds
• Suitable for autocross applications
• Suitable for road-course applications
• Suitable for compatible drag-racing applications
• Does not include ball-joint hardware
• Does not include shock or spring hardware
• Does not include steering or sway-bar hardware
• Does not include subframe-to-body hardware
• Does not include rear-suspension hardware
• UMI-2603 uses 14mm lower A-arm bolts
• UMI-2602 uses 1/2-inch lower A-arm bolts
• One complete kit services both sides of the vehicle
• UMI Performance part #2603
• Hawks Motorsports part #UMI-2603

5. MODEL INTERCHANGE AND FITMENT

UMI Performance catalogs #2603 for 1975-1981 Chevrolet Camaro and Pontiac Firebird F-body applications using 14mm metric front lower A-arm mounting hardware.

Fitment is determined by the upper and lower A-arm mounting arrangement and lower pivot-bolt diameter. It is not normally affected by engine size, transmission type, brake configuration, roof style or trim package when the vehicle retains compatible factory mounting dimensions.

Chevrolet Camaro Applications

• 1975 Chevrolet Camaro
• 1976 Chevrolet Camaro
• 1977 Chevrolet Camaro
• 1978 Chevrolet Camaro
• 1979 Chevrolet Camaro
• 1980 Chevrolet Camaro
• 1981 Chevrolet Camaro

Includes applicable:

• Camaro Base
• Camaro Sport Coupe
• Camaro Rally Sport
• Camaro LT
• Camaro Type LT
• Camaro Berlinetta
• Camaro Z28
• Camaro hardtop
• Camaro T-top
• Factory trim and appearance packages retaining the compatible front A-arm mounting arrangement

The Camaro Z28 was not offered for the 1975 or 1976 model years. Z28 fitment applies to 1977-1981 models.

Pontiac Firebird Applications

• 1975 Pontiac Firebird
• 1976 Pontiac Firebird
• 1977 Pontiac Firebird
• 1978 Pontiac Firebird
• 1979 Pontiac Firebird
• 1980 Pontiac Firebird
• 1981 Pontiac Firebird

Includes applicable:

• Firebird Base
• Firebird Esprit
• Firebird Formula
• Firebird Trans Am
• Turbo Trans Am
• Trans Am Special Edition
• Firebird hardtop
• Firebird T-top
• Factory trim and appearance packages retaining the compatible front A-arm mounting arrangement

Important Fitment Notes

• UMI-2603 services both front upper A-arms and both front lower A-arms.
• The upper and lower A-arms attach to the vehicle’s front subframe.
• One kit provides the primary mounting hardware for all four front A-arms.
• The lower A-arm pivot bolts are 14mm metric fasteners.
• Confirm the original lower A-arm bolt diameter before ordering.
• Compatible lower A-arm bushing sleeves must accept 14mm mounting bolts.
• Original, replacement or aftermarket A-arms must retain the compatible mounting width and sleeve dimensions.
• Confirm dimensions when installing custom-fabricated or heavily modified control arms.
• Inspect the subframe brackets and mounting holes before installation.
• Cracked, distorted, corroded or elongated mounting holes must be properly repaired before installing new hardware.
• Previous collision damage or subframe repairs may affect fitment and alignment.
• Modified or aftermarket front subframes may use different control-arm fasteners.
• Confirm compatibility directly with the subframe manufacturer when using a non-factory subframe.
• UMI-2603 does not mount the front subframe to the body.
• UMI-2603 does not include ball-joint, shock, spring, steering or sway-bar hardware.
• UMI-2603 is not intended for 1970-1974 F-body models using 1/2-inch lower A-arm bolts.
• UMI-2602 is the corresponding upper-and-lower A-arm hardware kit for verified 1970-1974 F-body applications.
• UMI-2601 provides upper A-arm mounting hardware only.
• UMI also catalogs #2603 for selected 1978-1996 GM B-body vehicles, but those vehicles should be covered by a separate B-body-specific product listing.

6. INSTALLATION NOTES

• Review the applicable GM service manual and control-arm manufacturer’s instructions before installation.
• Confirm that the vehicle is a 1975-1981 Camaro or Firebird with 14mm lower A-arm mounting hardware.
• Compare the supplied fasteners with the original hardware before beginning disassembly.
• Park the vehicle on a solid, level surface.
• Chock the rear wheels before raising the front of the vehicle.
• Safely raise and support the vehicle using properly rated lifting equipment.
• Support the vehicle at approved subframe or chassis locations.
• Never work beneath a vehicle supported only by a hydraulic jack.
• Front coil springs and coilover assemblies can store substantial energy and may cause serious injury if improperly handled.
• Safely unload and control the front suspension before removing a lower A-arm.
• Remove the front wheels to provide proper access to the suspension mounting points.
• Support the lower A-arm and spindle assembly during disassembly.
• Follow the correct procedure for disconnecting the sway-bar end link, shock, steering linkage and ball joints.
• Replacing one side at a time can help preserve component orientation and provide an installation reference.
• Record the direction and position of the original upper and lower A-arm fasteners before removal.
• Record the location and thickness of the upper-control-arm alignment shims before disassembly.
• The original shim arrangement may provide a starting point, but it does not replace a professional alignment.
• Inspect the original fasteners for bending, damaged threads, corrosion or movement inside the mounting holes.
• Inspect the subframe mounting brackets for cracking, corrosion, distortion or elongated holes.
• Inspect the upper-control-arm cross shafts and mounting surfaces.
• Inspect the lower A-arm bushing sleeves before installing the supplied fasteners.
• Confirm that the lower bushing sleeves accept the supplied 14mm bolts.
• Do not force a bolt through a misaligned sleeve or damaged subframe bracket.
• Correct component alignment before inserting the mounting bolts.
• Apply bushing lubricant only when directed by the control-arm manufacturer.
• Position each A-arm in the subframe and initially install its mounting hardware loosely.
• Confirm that each bolt passes completely through the mounting brackets and bushing sleeve.
• Verify full thread engagement through every nylon-insert locking nut.
• Do not position the nylon locking insert over an unthreaded section of the bolt.
• Do not install fasteners with damaged, contaminated or cross-threaded threads.
• Follow the applicable GM service manual or control-arm manufacturer’s tightening procedure.
• UMI does not publish one universal torque specification for UMI-2603 across every compatible factory and aftermarket control arm.
• Do not select a torque specification solely from the fastener diameter.
• Rubber- and polyurethane-bushed lower A-arms may require final tightening with the suspension positioned at normal ride height.
• Tightening certain bushed control arms with the suspension hanging can create unwanted bushing preload.
• Follow the control-arm manufacturer’s instructions when using Delrin, bearing or solid-pivot A-arms.
• Reinstall the coil springs, shocks or coilovers according to their manufacturer’s instructions.
• Reconnect the ball joints and steering linkage using the applicable service procedure.
• Confirm that castle nuts are secured with the correct cotter pins where required.
• Turn the steering from lock to lock after installation.
• Check clearance around the wheels, tires, brake hoses, steering linkage, sway bar, springs, shocks, control arms and subframe.
• Verify that the upper and lower A-arms move through their intended suspension travel without binding.
• Complete a professional front-end alignment after removing or replacing the upper or lower A-arms.
• Reinspect the mounting hardware after the initial road test.
• Periodically inspect the control-arm hardware and subframe mounting points as part of normal suspension maintenance.