Corvettes have always been known as good-handling cars, but until the debut of the C4 with its transverse leaf suspension, the hardware up front was conventional. In Corvettes prior to the C4, the layout consisting of unequal-length A-arms with coil springs was as ordinary as could be, surprisingly similar to GM's standard passenger cars. The General went a long way toward setting the Corvette suspension apart from its more pedestrian products, refining spring rates and damping into some very effective packages. However, the system had its limitations. The C4, which set a new milestone for handling for a domestically produced automobile, departed radically from that template. Up front, this lightweight suspension utilized a transverse composite monoleaf arrangement, a layout used in Corvettes ever since.
Vette Brakes & Products (VBP) offers an interesting alternative for earlier Corvettes, blending the borrowed concept of a modern transverse-leaf system with the latest in aftermarket composite monoleaf technology. A simple bolt-on kit adapts the layout of a coil-sprung Corvette to take advantage of a lightweight transverse-mounted monoleaf. The modification revolves primarily around doing away with the coil springs by accepting a single under-slung leaf. A bolt link similar to that found at the rear of a conventional Corvette IRS transfers the spring load to the outer extremity of the lower control arm to support the front suspension. The configuration provides a means for individually fine-tuning and adjusting the ride height. The suspension's wheel rate is adjustable by selecting one of four possible clamping positions at the spring's inner mount. The end result is an adjustable, modern system providing a dramatic reduction in unsprung weight and a far more responsive and compliant front suspension. The light composite monoleaf spring can react at a much higher frequency than the heavy, stock, steel coil springs, negating a noticeable level of on-the-road harshness, particularly compared to coils of a similar spring rate.
Our friend Richard Czerny was eyeing just such a conversion for his '75 roadster. VBP offers several different levels of upgrade, from its comprehensive Master Suspension kit to the simple monoleaf-spring conversion. Richard selected the complete front monoleaf system, PN 42030, which includes new lower control arms fabbed to mate with the monoleaf system. For the rear, a spring replacement kit (PN 42333) was chosen to replace the heavy and harsh stocker with a composite monoleaf.
Richard's goal was to improve some of the characteristics inherent in the car's earlier suspension. As he tells it, "My primary reason for first looking at this suspension may seem superficial, but it was the ability to lower the car and adjust the ride height that first drew my attention. I've been down the road of cutting coil springs before, and the ride just went from bad to worse. The ride and rattles were two aspects of my Corvette I found the most difficult to accept, and the suspension swap seemed like a way to address both of these issues. The handling was satisfactory for me with the stock suspension on smooth roads, but my gut cringed at the sight of bumps, especially on curves. The car just felt like it wanted to fall apart, with the dash and body rattling in a way that was unpleasant.
We dropped in the composite monoleaf suspension, and it's a different car. The same kinds of rough roads that made me wince aren't an issue anymore, the rattle is gone, and so is the shimmy I got on the rougher stretches of road. I've done many alterations to the car, some minor and some major, such as modifying the engine and adding the four-speed. This suspension swap turned out to be one of the greatest improvements of them all."