What is the Shelby Drop & Wedge Plate Kit, and How Does It Improve Handling?

Posted By: Stang-Aholics Website Staff

Upper Control Arm Drop and Wedge Plate Kit- 4 Bolt

Basic concept

  • The kit relocates the pivot point of the upper control arms (UCAs) by lowering them inside the shock towers — a technique historically known as the “Shelby Drop,” originally used on early Ford Mustangs equipped by Carroll Shelby. 

  • As part of that relocation, the wedge plates included in the kit re-orient the upper ball joint mounting angle, to ensure proper geometry after the drop and prevent binding at the ball joint.

  • The kit from Stang-Aholics includes the wedge plates plus a drilling template to reposition the control-arm cross-shaft holes.

Fitment / Compatibility

  • Designed for 1964–1970 Mustangs.

  • Important: Must verify whether your upper control arms use 3-bolt or 4-bolt ball-joint mounting — the appropriate version of the wedge plates must be ordered accordingly.

Why Lower the Upper Control Arm Pivot (Benefits)

Relocating the UCA mount and using wedge plates delivers several interrelated performance benefits for classic Mustangs.

Lower center of gravity → reduced body roll

By lowering the pivot point of the UCAs, the car’s effective center of gravity is lowered modestly. This contributes to reduced body roll under cornering loads, helping the car stay flatter and more stable.

Improved camber curve — better front tire grip in corners

One of the primary benefits is an improved “negative camber curve.” As the suspension compresses under cornering, the wheel gains camber so the top of the tire tilts inward, keeping more of the tire tread in contact with the road. This improves front-end grip through turns, which makes steering more precise and handling more predictable. 

Correct ball-joint geometry and prevent binding

When you lower the UCA without correcting the ball-joint mount angle, the ball joint can bind (bind = limit articulation or cause uneven suspension motion) — especially near full droop or compression. The wedge plates in this kit reorient the ball-joint geometry to match the new control-arm position, ensuring smooth suspension operation. 

Better roll center behavior / reduced roll rate

Lowering the UCA pivot combined with a wedge kit can raise the car’s roll center relative to the suspension links (or effectively change roll center geometry), which changes how cornering loads are distributed. Less weight transfer onto the springs means less body roll and improved stability under lateral loads. 

What the Stang-Aholics Kit Provides & What to Know

  • This kit is sold as a full set — wedge plates (for both sides) plus a drill template to relocate the upper control-arm cross-shaft mounting holes.

  • It comes in variants to match either 3-bolt or 4-bolt ball-joint UCA designs. It’s critical to inspect your existing UCA to determine which version you need before ordering. 

  • According to the manufacturer, the modification improves front-end geometry, lowers the center of gravity, improves negative camber under load, and increases front-tire grip through corners. 

  • This is a relatively straightforward upgrade that is “simple yet effective” — as it can deliver noticeable handling/performance benefits with relatively modest cost and effort compared to more extensive suspension overhauls. 

  • When installers complete the upper control-arm drop, we also recommend looking into some of the complementary suspension upgrades we offer — improved shocks, dual-rate lowering springs, upgraded Delrin bushings, and heavy-duty cross-shaft kits. These additional components are often recommended by the manufacturer and our staff when you are looking for a more complete and even more thorough front-end handling improvement. 

Engineering Considerations & Best Practices

  • Verify ball-joint mount type carefully (3-bolt vs 4-bolt) before ordering — mismatching this will prevent proper installation of wedge plates.

  • Use the correct drill template: Each kit includes a template — using it ensures the new UCA pivot holes are in the right place for safe and effective geometry.

  • Alignment required after installation: Because camber, caster (and possibly toe) will change significantly, a full front-end alignment is necessary after the modification.

  • Complement with other suspension components if possible: While the UCA drop & wedge plates improve geometry, pairing with better shocks, springs, and proper upgraded bushings will maximize the performance gains.

  • Expect modest ride-height change: The drop lowers UCA pivot — the actual ride-height drop of the car may be modest or need tuning (springs, rear suspension) to avoid excessive “nose-low” stance.

Why This Upgrade Still Matters for Classic Mustang Owners

Even decades after their original design, first-gen Mustangs benefit from modern understanding of suspension geometry. The Shelby-Drop + wedge-plate approach is often regarded as one of the most effective and affordable foundational upgrades to improve handling for street, occasional spirited driving, or light performance use. As many Mustang-performance guides put it, relocating the upper control arms is “the time-honored Shelby trick” to tame the front-end geometry of ’65–’70 Mustangs.

Because the components are relatively simple (plates and drilling template), installation is pretty straightforward compared to full custom suspension builds — making it especially appealing for garage restorers, hot-rodders, and owners who want more cornering stability without overly aggressive suspension setups.

Summary

The Stang-Aholics 1964–1970 Mustang Wedge Plates & UCA Drop Kit modernizes the classic Mustang suspension by lowering the upper control-arm pivot and re-orienting the ball joint geometry. The result: lower center of gravity, improved camber gain under load, better front-tire traction during cornering, reduced body roll, and more stable handling. For any vintage Mustang owner seeking to extract better feeling and sharper road performance from an otherwise stock suspension — with minimal cost and effort — this "Shelby-Drop" kit remains a highly effective, proven upgrade.

Ready to Start Transforming your Mustang’s performance?
Grab your Upper Arm Drop and Wedge Kit Here from Stang-Aholics!

Looking for Complimentary Components for this Upgrade?  We have you covered, take a Look at some of the links below!

1964-66 Mustang RideTech Street Grip Dual-Rate Front Coil Springs

1967-70 Mustang RideTech Street Grip Dual-Rate Front Coil Springs

1964-66 Mustang RideTech Street Grip Front Adjustable Mono Tube Shock Upgrade

1967-70 Mustang RideTech Street Grip Front Adjustable Mono Tube Shock Upgrade

1964 - 1966 Mustang Street Grip Delrin Control Arm Bushings and Cross Shafts

1967 - 1970 Mustang Street Grip Delrin Control Arm Bushings and Cross Shafts

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