The MGA suspension is independent at the front, with double wishbones and coil springs, and Armstrong lever arm shock absorbers whose arms form the upper wishbones, and a conventional live rear axle located by semi-elliptic leaf springs with Armstrong lever arm dampers at the rear. The steering is rack-and-pinion, supplied by Cam Gears, and is broadly common across all variants with one significant difference on the Twin Cam and De Luxe. While the suspension layout is broadly shared across the MGA range, the front hubs and steering knuckles are variant-specific because of the three different front brake systems used during production. Several production-change points within the pushrod 1500 also affect front springs, knuckles, and anti-roll bar provision.
This section covers all suspension and steering components from the front wishbones and rear leaf springs through to the steering column, rack and wheel.
Front suspension
The independent front suspension design was carried over from the earlier TD and TF models, featuring double wishbones and coil springs with the Armstrong shock absorber arms forming the upper wishbones. The main areas where suspension components differ between MGA variants are the steering knuckles and hubs, which were of different types on the 1500, the Twin Cam / De Luxe, and the 1600 / 1600 Mk II cars, to accommodate the three different front brake types, Lockheed drums on the 1500, Dunlop discs on the Twin Cam / De Luxe, and Lockheed discs on the 1600 / 1600 Mk II. Wire-wheeled cars have different hubs from disc-wheeled cars, giving a matrix of front hub specifications that must be confirmed against the car's variant and wheel type before ordering.
Front coil springs and knuckle modifications
On the 1500, new front coil springs were introduced from car/chassis 15152. They were made from thicker-gauge wire and had a reduced free length to stiffen the front suspension, and are only interchangeable in pairs. The steering knuckles and nuts were modified from car/chassis 54247 with washers being added. These two breakpoints should be checked when ordering front suspension components for a 1500.
The Twin Cam received the same stiffer coil springs and knuckle modifications from the start of Twin Cam production.
Anti-roll bar
From car/chassis 66574, the spring pans were modified to permit installation of an optional anti-roll bar, with corresponding changes to the lower wishbones. The anti-roll bar was fitted as standard on all Twin Cam cars from car/chassis 2275 and on all De Luxe variants, but remained optional on the standard 1600 and 1600 Mk II cars. The Andrex friction-type TE.1 competition shock absorber (available for all models except the 1600 Mk II) should not be fitted in conjunction with the anti-roll bar, the two are mutually exclusive options.
Front shock absorbers
The same Armstrong double-acting lever arm piston-type shock absorber was fitted to all MGA variants at the front. The shock absorber bodies are in natural aluminium with the arms painted black. Andrex friction-type TE.1 competition shock absorbers were available for fitment alongside the standard Armstrong items (except on the 1600 Mk II), with special mounting brackets. Twin Cam cars could be fitted with higher-setting hydraulic valves to the front (and rear) shock absorbers, recommended for circuit racing, an option that appears to have been available from around January 1959.
Front suspension geometry
Factory front suspension data is as follows, common to all MGA variants: camber angle 1° positive to ½° negative; castor angle 4°; king pin inclination 9° to 10½°; toe-in nil (wheels parallel). These settings apply across the 1500, 1600, 1600 Mk II and Twin Cam specifications and should be used as the reference values for restoration set-up.
Rear suspension
The MGA rear suspension uses conventional semi-elliptic leaf springs with six leaves (including the master leaf) and a bottom plate, fitted below the rear axle and secured with U-bolts. There is no interleaving between the spring leaves. Bump rubbers and rebound straps control the extremes of axle movement. Armstrong lever arm shock absorbers in natural aluminium with black-painted arms are fitted inside the chassis frame side members in front of the axle.
Individual spring leaves are 7/32 inch gauge and 1¾ inches wide, with a free length of 42½ inches (+0 / -1/8 inch). The distance between the spring eyes is 42 3/16 inches (free) and 42½ inches at a working load of 450 lbs. Free camber is 3.6 inches, and camber at working load is zero. The rear suspension, springs and dampers were the same on all models and were not subject to any production-change modifications.