Product Description:
Hawks Motorsports is proud to offer our clients this : 1970-1981 Camaro, Firebird, Esprit, Formula, and Trans Am Rear Leaf Spring Polyurethane Isolator and U-Bolt Installation Kit from UMI Performance.
UMI Performance #2627 provides the isolator pads, heavy-duty U-bolts, front spring-eye bolts, washers, and nuts required when installing compatible stock-location rear leaf springs on a second-generation GM F-body.
The kit is designed to work with UMI #2620 two-inch lowering rear leaf springs and other compatible stock-location leaf springs. It is suitable for factory-style restorations, performance-street vehicles, Pro-Touring builds, autocross cars, and other applications retaining the stock rear leaf-spring mounting arrangement.
Four performance-polyurethane isolator pads replace the original rubber pads positioned above and below the rear leaf springs. Original rubber isolators frequently become crushed, cracked, distorted, or oil-soaked after decades of service. Replacing them helps properly locate the springs against the axle housing and lower spring plates.
UMI #2627 replaces the original combination of U-bolts and T-bolts with four heavy-duty U-bolts. This provides consistent clamping on both sides of the rear axle and is especially beneficial on vehicles producing increased horsepower and traction.
The supplied U-bolts are manufactured from steel and protected with a zinc-plated finish. Eight thick washers and eight high-hex nuts are included for securing the U-bolts to the original-style lower spring plates.
Two 1/2-13 x 5-inch Grade 8 bolts, two flat washers, and two locking nuts are supplied for the front leaf-spring-eye mounting locations. This allows both the driver and passenger-side front spring-eye bolts to be replaced during installation.
UMI Performance manufactures the kit in the USA. It can be used as part of a complete UMI rear suspension installation or when replacing compatible stock-location rear leaf springs.
Complete Kit Contents
- One four-piece polyurethane rear leaf-spring isolator pad set
- Four heavy-duty U-bolts
- Eight 7/16-inch thick washers
- Eight high-hex U-bolt nuts
- Two 1/2-13 x 5-inch Grade 8 front spring-eye bolts
- Two 1/2-inch flat washers
- Two 1/2-13 locking nuts
Important Package Information
This is an installation and isolator kit. Rear leaf springs, front leaf-spring mounting buckets, lower spring plates, rear shackles, rear shackle bushings, shocks, and axle components are not part of UMI #2627.
UMI #2625 polyurethane shackle kit and UMI #2626 Delrin shackle kit are separately available options for replacing the rear leaf-spring shackle assemblies and bushings.
4. KEY FEATURES
- Designed for 1970-1981 second-generation GM F-body vehicles
- Fits Chevrolet Camaro applications
- Fits Pontiac Firebird, Esprit, Formula, and Trans Am applications
- Designed for the rear leaf-spring suspension
- Complete isolator, U-bolt, and front spring-eye bolt installation kit
- Works with UMI #2620 rear lowering leaf springs
- Works with other compatible stock-location rear leaf springs
- Suitable for factory-height and lowering springs retaining stock mounting locations
- Intended for multi-leaf rear spring applications
- Suitable for restoration and performance applications
- Useful when replacing worn or damaged original leaf-spring mounting components
- Includes a four-piece polyurethane leaf-spring isolator set
- Two isolator pads are used for each rear leaf spring
- Replaces worn, cracked, crushed, or deteriorated original rubber isolators
- Polyurethane construction provides increased durability
- Helps properly locate the leaf springs against the axle housing
- Helps maintain proper contact between the axle, springs, and lower spring plates
- Includes four heavy-duty steel U-bolts
- Replaces the original U-bolt and T-bolt mounting arrangement
- Provides U-bolt clamping on both sides of the rear axle
- Suitable for increased-horsepower applications
- Also suitable for stock and mildly modified vehicles
- Zinc-plated U-bolt finish
- Includes eight thick U-bolt washers
- Includes eight high-hex U-bolt nuts
- Includes two 1/2-13 x 5-inch Grade 8 front spring-eye bolts
- Includes two 1/2-inch flat washers
- Includes two 1/2-13 locking nuts
- Supplies front spring-eye fasteners for both leaf springs
- Compatible with the applicable original lower spring plates
- Compatible with applicable factory front spring mounting buckets
- Can be combined with UMI #2625 polyurethane rear shackle kit
- Can be combined with UMI #2626 Delrin rear shackle kit
- Suitable for street-driven vehicles
- Suitable for Pro-Touring applications
- Suitable for autocross and corner-carving builds
- Suitable for drag-racing applications
- Direct-fit configuration for compatible factory-style suspension arrangements
- Official UMI installation instructions provide torque specifications
- Manufactured in the USA
- UMI Performance part #2627
5. MODEL INTERCHANGE AND FITMENT
UMI Performance catalogs #2627 for 1970-1981 Chevrolet Camaro and Pontiac Firebird models equipped with compatible stock-location rear leaf springs.
Chevrolet Camaro Applications
- 1970 Chevrolet Camaro
- 1971 Chevrolet Camaro
- 1972 Chevrolet Camaro
- 1973 Chevrolet Camaro
- 1974 Chevrolet Camaro
- 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 and Sport Coupe
- Camaro Rally Sport
- Camaro Super Sport
- Camaro Type LT
- Camaro Berlinetta
- Camaro Z28
- Other second-generation Camaro trim and appearance packages equipped with compatible stock-location rear leaf springs
Pontiac Firebird Applications
- 1970 Pontiac Firebird
- 1971 Pontiac Firebird
- 1972 Pontiac Firebird
- 1973 Pontiac Firebird
- 1974 Pontiac Firebird
- 1975 Pontiac Firebird
- 1976 Pontiac Firebird
- 1977 Pontiac Firebird
- 1978 Pontiac Firebird
- 1979 Pontiac Firebird
- 1980 Pontiac Firebird
- 1981 Pontiac Firebird
Includes applicable:
- 1970-1981 Pontiac Firebird
- 1970-1981 Pontiac Firebird Esprit
- 1970-1981 Pontiac Firebird Formula
- 1970-1981 Pontiac Trans Am
Important Fitment Notes
- Designed for 1970-1981 second-generation GM F-body vehicles.
- Designed for compatible stock-location rear leaf springs.
- Works with UMI #2620 two-inch lowering leaf springs.
- Works with other rear leaf springs that retain the original mounting arrangement.
- Designed for multi-leaf rear spring applications.
- Fits applicable coupe, hardtop, and factory T-top models.
- Verify the vehicle retains compatible front spring mounting buckets and lower spring plates.
- Original lower spring plates must be structurally sound and free from severe corrosion, cracks, deformation, or elongated mounting holes.
- Inspect the front spring-eye mounting buckets and surrounding floor structure for rust or previous damage.
- The polyurethane isolator alignment openings must match the spring locating pins and axle spring-perch locations.
- The axle housing must sit fully against the upper isolator and spring locating pin.
- Applications with aftermarket rear axle housings, modified spring perches, non-original axle-tube dimensions, or aftermarket spring plates must be checked before installation.
- The supplied U-bolts are intended to replace the original U-bolt and T-bolt arrangement.
- The factory rear brake line may require minor repositioning where the new U-bolt replaces the original T-bolt.
- Brake lines must not be crushed, stretched, kinked, or allowed to contact the U-bolts.
- UMI #2627 does not include rear leaf springs.
- UMI #2627 does not include rear spring shackles or shackle bushings.
- UMI #2627 does not include front leaf-spring mounting buckets.
- UMI #2627 does not include lower spring plates.
- UMI #2625 polyurethane rear shackles are available separately.
- UMI #2626 Delrin rear shackles are available separately.
- This application does not fit 1967-1969 first-generation Camaro or Firebird models.
- This application does not fit 1982-1992 third-generation Camaro or Firebird models.
6. INSTALLATION NOTES
- Read the complete UMI installation instructions before beginning work.
- Verify all supplied components against the official parts list.
- Park the vehicle on a solid, level surface.
- Safely raise and support the vehicle using properly rated lifting equipment.
- Never work beneath a vehicle supported only by a hydraulic jack.
- Support the vehicle by the chassis near the front leaf-spring mounting areas.
- The rear axle must be separately supported and capable of being raised or lowered during installation.
- Remove the rear wheels for working access.
- Disconnect the lower shock mounts from the lower spring plates.
- Remove the existing U-bolt and T-bolt nuts from the lower spring plates.
- Carefully raise the axle housing away from the leaf springs.
- Original isolators may stick to the axle perch, spring, or lower plate and require careful separation.
- Remove the three bolts securing each front leaf-spring mounting bucket to the chassis.
- Support the leaf spring while removing the final front mounting-bucket bolt.
- Replace each original front spring-eye bolt with the supplied 1/2-13 x 5-inch Grade 8 bolt.
- Position the supplied flat washer beneath the locking nut.
- UMI specifies tightening the front spring-eye bolts to 50 ft-lb.
- Position the upper polyurethane isolator between the leaf spring and axle perch.
- Make sure the leaf-spring alignment pin engages the corresponding opening in the isolator and axle perch.
- The axle housing should settle completely into its correctly located position.
- Do not tighten the assembly if the locating pin is resting against the isolator instead of passing through its alignment opening.
- Install the four supplied U-bolts around the axle housing.
- Position the lower polyurethane isolator pads beneath the leaf springs.
- Reinstall the original-style lower spring plates.
- Inspect the factory brake lines before tightening the U-bolts.
- Minor brake-line repositioning may be required where a new U-bolt replaces an original T-bolt.
- Maintain adequate clearance between the U-bolts and brake lines.
- Install the eight thick washers and high-hex nuts.
- Tighten the spring-plate nuts gradually using an alternating crisscross pattern.
- Tighten each nut evenly so the lower spring plate remains level.
- UMI specifies a final spring-plate nut torque of 45 ft-lb.
- Reconnect the lower shock mounts.
- Repeat the installation procedure on the opposite side.
- Inspect both sides to verify that the axle, isolators, springs, and lower plates are centered and seated correctly.
- Confirm that no brake line, parking-brake cable, fuel line, shock, exhaust component, or other part contacts the U-bolts.
- Recheck all connections and torque values following the initial road test.
- Periodically inspect the U-bolts, nuts, isolators, and spring plates as part of normal suspension maintenance.
