The MGF is a classic British roadster known for its nimble handling and unique Hydragas suspension system. Over time, suspension components wear out, leading to a bouncy ride, uneven tire wear, or poor handling. Whether you're restoring an MGF or maintaining a daily driver, finding the right suspension spare parts is essential. This guide covers the common suspension parts for the MGF, what to look for when buying replacements, and tips for a successful installation.
Understanding MGF Suspension Systems
The MGF originally came with two suspension types: the standard Hydragas system and the later Hydragas with a sportier tune. Hydragas uses interconnected fluid and gas spheres instead of traditional coil springs. This system requires specific spare parts, but many owners also convert to coilover setups. The key components to consider include:
Hydragas Spheres and Dampers
The heart of the MGF suspension is the Hydragas sphere at each wheel. These spheres contain pressurized nitrogen gas and hydraulic fluid, providing both springing and damping. Over time, spheres can lose pressure, leading to a harsh or sagging ride. Replacement spheres are available, but you must choose the correct ones for your car's year and options (standard or sport). Some aftermarket suppliers offer refurbished spheres at a lower cost. If the damping is gone, you may need to replace the entire unit, as the damper is integral to the sphere.
Coil Spring Conversion Kits
A popular upgrade is to replace the Hydragas system with a conventional coilover setup. This simplifies maintenance and improves handling consistency. Several manufacturers produce bolt-in coilover kits for the MGF, including units with adjustable damping and ride height. When buying a conversion kit, ensure it comes with top mounts and bearings, as these are often specific to the MGF. Check for spring rates appropriate for your driving style (soft for road, stiffer for track).
Wishbones and Control Arms
The MGF uses double wishbone suspension front and rear. The wishbones can wear at the bushings and ball joints. Replacement wishbones are available as complete assemblies or as separate components. OEM quality arms are made by Delphi or Lemförder, but budget options exist. Inspect the ball joint boots for cracks and the bushings for play. If you're replacing just the bushings, consider polyurethane upgrades for longer life and sharper steering.
Anti-Roll Bars and Drop Links
Anti-roll bars (sway bars) reduce body roll. The MGF front and rear bars connect via drop links. Stock drop links are plastic and prone to failure. Replace them with metal or heavy-duty polyurethane versions. The anti-roll bar bushings also wear; polyurethane replacements are inexpensive and improve responsiveness. If you're upgrading to a thicker anti-roll bar, ensure it's compatible with your wheel offset.
Track Rod Ends and Steering Rack
While not strictly suspension, track rod ends affect wheel alignment and steering feel. Worn tie rods cause play and wandering. OEM brands like TRW or Moog are reliable. The MGF steering rack is mounted at the rear; check for leaks and play in the pinion. If the rack needs replacement, consider a quick-ratio rack from a later model.
How to Choose the Right MGF Suspension Parts
Selecting the correct spare parts requires attention to vehicle specifics. Here are practical guidelines:
Check Your VIN and Suspension Code
The MGF's suspension options evolved over the years. The VIN plate includes a suspension code (e.g., SL, ST). Spheres and springs differ between standard and sport models. Using the wrong parts can compromise ride height and handling. Consult an MGF parts database or specialist to decode your VIN.
OEM vs Aftermarket
OEM (Original Equipment Manufacturer) parts like those from Rover or AP Lockheed are direct replacements. Aftermarket options vary widely. For Hydragas spheres, quality brands include MGF Mania, Kelvedon, or Brown & Gammons. For coilover kits, BC Racing and YSR offer good value. Avoid unbranded parts from unknown sources, as they may have poor quality seals or incorrect spring rates.
Buy Complete Sets vs Individual Parts
When replacing shocks and springs, it's wise to replace all four corners at once. Old parts can mask new ones and lead to uneven handling. For bushings, a polyurethane kit replaces all suspension bushings at a lower cost than buying individually. However, if only one component is worn, a single replacement is acceptable.
Installation Tips and Common Pitfalls
Working on MGF suspension requires some special tools and caution. Here are key points:
Hydragas Depressurization
Before removing any Hydragas component, you must depressurize the system to avoid fluid spray. Use a dedicated depressurizer tool or carefully loosen the bleed screw on the sphere. Never attempt to dismantle a pressurized sphere.
Alignment After Assembly
Any suspension work will alter the wheel alignment. After replacing wishbones, track rod ends, or coilovers, take the car for a professional alignment. The MGF has some adjustment, but camber may be fixed. Make sure the installer has correct specs for your model (e.g., toe setting for sport or standard).
Torque Specifications
Suspension bolts must be tightened to the correct torque with the car's weight on the suspension (under load). Use a torque wrench and follow a workshop manual. Common torque values: lower arm bolt to subframe: 85 Nm; damper top mount nut: 25 Nm; ball joint pinch bolt: 35 Nm. Over-tightening can cause bushings to bind.
Final Recommendation
For most MGF owners, the best approach is to start with a thorough inspection. Identify worn parts by checking for play, leaking fluid, or abnormal tire wear. If the Hydragas spheres are original and over 20 years old, replace them regardless of condition. A refurbished sphere set from a reputable supplier offers the best balance of cost and performance. If you want to improve handling, consider a coilover conversion from a specialist like BC Racing, paired with polyurethane bushings. Always buy complete kits when possible and avoid mixing old and new components. Finally, budget for a professional alignment after installation. With the right MGF spare parts suspension, you can restore that classic roadster feel and extend the life of your car for years to come.