Late-Model Suspended '61, Part 1

Out With the Old, Under with the New

Andy Bolig Jun 1, 2002 0 Comment(s)

Step By Step

This is the heart of the swap. The frame supplied by SRIII Motorsports comes ready for installation of the C4 suspension pieces. Adjustment of the suspension is exactly as GM designed it, and the only variation to the C4’s suspension specifications is the narrower width and the use of coilover shocks in place of the transverse composite spring.

Why would we upgrade the suspension without also jumping forward for a powerplant? The star of the show is this LS1 from GM Performance Parts. SRIII Motorsports provides the mounting necessary to make installing one of these a bolt-in process. We used a six-speed from a 2000 Camaro, along with the flywheel and clutch. The transmission mount was final-fit and welded by Fauver Machine & Welding in Sanford, Florida, to ensure strength. With the LS1, the six-speed, and suspension, this generation-jumper will definitely make an excellent driver!

One of the concerns with swapping in a later engine is having the necessary wiring. GM Performance Parts simplified that with its crate engine by providing a wire harness, a fuse block, and a computer. The time saved scouring salvage yards for a usable engine, computer, and harness could be put to good use actually wrenching on the car.

One of the major benefits of using a newer Corvette suspension is the independent rear suspension. This requires a secure mounting for the differential, which is provided by the strut-rod mounts in the rear and the mounting for the driveline support beam in the front.

Another benefit of the later C4s is the use of antilock brakes. Corvette Central provided a set of its wheel bearings. We opted for the ’91-’96 bearings because they have the wheel-speed sensor and plug contained within the bearing. This car will have ABS, so the sensors are necessary. We used the front suspension from an ’85, so we needed to remove the material from the back of the steering knuckle to provide room for the sensor plug, and the bearing bolts are more vertical instead of horizontal like they would be on a ’91-’96 knuckle.

New bearings also went on the rear of our Corvette, as well as provisions for the speed-sensor wheel on the spindle.

All of the suspension pieces were sent to Advanced Powder Coating of Florida before assembly. The powdercoating protects the parts, and cleans up easily. Vette Brakes & Products (VBP) supplied the necessary polyurethane bushings for the front and rear suspension. We wanted to make this suspension handle as best as possible, and these were necessary parts to achieve that goal.

The suspension is highly adjustable, which is another benefit to this swap. The straight-axle Corvettes were limited as to the amount of adjustment that could be made. With this new system, today’s technology can be used to get the best ride, handling, and tire wear.

Because the track width of the suspension is narrower than even an early C4, the transversely mounted spring will not work. Using coilover shocks from QA1 adds to the adjustability of this system. The ride height and firmness of the shocks are now adjustable. The small dial adjusts the shocks for 12 positions ranging from soft to firm.

With all the bushings, bearings, and U-joints installed, the rear end started to look like a million bucks.

Before we could install the front knuckles, we had to install the Corvette Central-supplied ball joints. The upper ball joints simply bolted in place, while the lower ball joints had to be pressed into place.

Installing the steering knuckle really started to make this suspension show potential. Compare the technology of this suspension to that of an original straight-axle, and it becomes apparent why someone would want to perform this swap.

VBP supplied its Big Brake Upgrade Kit for our suspension. The Girling two-piston calipers, mated with the optional slotted rotors, will add increased stopping and a larger margin of safety than the original drum brakes could ever hope to provide. Everything from brake pads to flex hoses are included in the kit.

We installed a set of wheels so we’d have a rolling chassis. So far, this has been a straightforward bolt-on job. It almost seems a shame to cover this suspension with a body, but how else could you enjoy it?

Of course, you need a body to put over the suspension. Ours is this nice ’61, but SRIII Motorsports can make a frame to fit any ’53-’62 Corvette. We removed the body in preparation of a trial-fit.

Many people today enjoy the comfort, handling, and driveability of the later Corvettes. Others savor the lines, styling, and character of the earlier, straight-axle models. Some blessed folks get to have both! The Corvette Clinic was commissioned to bind the styling and persona of this ’61 Corvette with the handling and power of a Corvette one tenth its age. We decided to follow along on the buildup.

Such a swap has several benefits. First, you get to enjoy your Corvette’s new-found driveability, handling, power, safety, and reliability while the original chassis and engine quietly bide the time in storage, protecting them from the mileage and ravages of the open road. If you ever decide that an original Corvette better suits your changing lifestyle, the original chassis can be ordered back into service—truly, the best of both worlds.

COMMENTS

TO TOP