AST x MOTON Coilovers for the BMW M3 & M4 (F8X / G8X)

Why AST x MOTON Suits the M3 & M4

The F8X and G8X share a fundamental handling character: a long wheelbase, front-heavy weight bias from the twin-turbo S55 or S58, and a multi-link rear that becomes sensitive to spring rate and damper tune the moment you move beyond factory sport settings. Off-the-shelf coilovers that try to "do everything" typically end up riding harsh on the street and under-damped on track.

AST and MOTON don't work that way. Every set is built to order against a spring rate and valving spec that matches how you actually drive the car — road, club day, time attack, or GT-class endurance. The dampers are monotube, fully rebuildable, and revalvable, so a set bought for street use today can be respec'd for track use three years later without throwing the hardware away.

AST sits across the street-to-semi-pro bracket (5100 Street, 5100 Competition, 5200 2-way, 5300 3-way). MOTON sits above it — a true motorsport tier designed for endurance and professional GT use. Both are developed in the same Dutch facility, share the same serviceability philosophy, and cover every F8X and G8X variant we've been asked for.

AST x MOTON for the F80 M3 & F82 / F83 M4 (2014–2018)

The S55-powered F8X is now firmly in the enthusiast sweet spot — values have stabilised, the aftermarket is mature, and a growing number of owners are moving these cars toward serious track use. The factory EDC dampers are a common first upgrade target: capable enough on the road, but limited in range and non-serviceable once they're worn.

We source the F8X in Pre-LCI (2014–2015, 3-bolt top mounts) and LCI (2015–2018) configurations:

• AST 5100 Competition: Inverted monotube, single-adjust damping, with camber-adjustable front top mounts. The benchmark for a fast-road-plus-trackday F8X.
• AST 5200 Series (2-Way): Independent compression and rebound with remote reservoirs. For drivers who've outgrown single-adjust and want to separate corner-entry and corner-exit behaviour.
• AST 5300 Series (3-Way): Rebound, low-speed compression, and high-speed compression, each on its own knob. The top of the AST range, suited to time attack and semi-pro track use.
• MOTON 1-Way Clubsport: The entry point into the MOTON range. Non-inverted monotube, 1-way with 12-position rebound, camber-adjustable front tops. A strong step up over a used OEM EDC setup for club-level track use.
• MOTON 2-Way Clubsport: Inverted, monotube, independent rebound and compression with remote reservoirs. 15-step damping adjustment. Built for serious club racing.
• MOTON 3-Way Motorsport: Inverted, monotube, with elevated top guide and helper piston to reduce friction. Independent rebound, low-speed compression, and high-speed compression. This is the damper specification running in endurance and GT programmes worldwide.

Pair with Suspension Secrets Adjustable Camber & Caster Plates (F8X) to unlock the front-end geometry the factory doesn't give you, and the Suspension Secrets Full Kinematics Kit (F8X) for the complete rear-end geometry overhaul.

AST x MOTON for the G80 M3 & G82 / G83 M4 (2021+)

The G8X has rewritten the performance sedan rulebook. The S58 makes more torque than anything BMW has ever fitted to an M-car, and the chassis is built to handle it — but the factory M Adaptive damping, while genuinely good on the road, is a closed system with a fixed tune and no rebuild path.

For G8X owners, we supply three distinct routes:

1. AST Adjustable Lowering Spring (ALS) system. This is the hero product for G8X RWD owners who want to drop the car 20–30mm, improve dynamic response, and keep factory M Adaptive damping working exactly as BMW intended. The ALS is not a lowering spring kit in the traditional sense — it's a progressive-rate spring system engineered around the factory damper's working range, so the adaptive logic stays in spec. For a G8X that spends its life on the road with occasional spirited use, this is the sweet spot.

2. AST 5100 / 5200 / 5300 Series coilovers. The full AST ladder is available for the G80, G82, and G83 in both RWD and xDrive variants. Built against G8X-specific spring rates and damper valving. 5100 Competition is the starting point for an owner who wants a proper coilover without 3-way complexity; 5300 is for G8X builds going hard on track.

3. MOTON 1-Way / 2-Way / 3-Way coilovers. MOTON G8X is made-to-order, built to the customer's spec sheet at the AST/MOTON facility. This is the tier for G8X chassis heading into time attack, endurance, or GT-class competition.

RWD vs xDrive matters on this platform — front spring rates and valving differ between the two, and so do the required part numbers. Confirm your variant before ordering, or drop us a message through the product page and we'll spec it correctly.

Tuning and Setup

A set of AST or MOTON coilovers is only as good as the setup running through them. Two blogs are worth reading before you order:

• 1-Way vs 2-Way vs 3-Way Adjustable Damping Explained — what each adjustment actually controls, and how the AST 5100, 5200, and 5300 Series map onto real-world driving.
• How to Adjust AST & MOTON Coilovers — the practical guide to where the knobs are, which way to turn them, and how to develop a baseline setup on your own car.

Once you're lowered, a full four-wheel alignment is non-negotiable — ride height changes alter camber, toe, and caster, and on the F8X and G8X the factory adjustment range is limited. Suspension Secrets arms, bushes, and camber plates give you the adjustment range the OEM setup doesn't.

Pair With Your M3 / M4 Brake and Chassis Upgrades

The F8X and G8X respond well to a coordinated upgrade path. A stiffer, lower, better-damped chassis exposes weaknesses elsewhere — typically in the brake system and in the rubber-bushed factory arms that weren't designed for sustained track loading.

• F8X brakes: DIXCEL Front Rotors (380×30mm, blue caliper), DIXCEL Rear Rotors (370×24mm), or AP Racing CP9665 / Alcon CAR99 / Brembo Pista big brake kits for tracked cars.
• G8X brakes: DIXCEL Front Pads (G8X), Alcon Front & Rear BBK, or the Brembo Pista 380×36 front kit.
• F8X chassis: Full Kinematics Kit, Camber & Caster Plates, rear toe and camber arms.
• G8X chassis: Front Offset Caster Bushes, adjustable front and rear drop links, monoball bushes.

Frequently Asked Questions

Which AST or MOTON series is right for my F8X or G8X?

For a street-primary car with occasional track days, AST 5100 Competition is the benchmark. For a dual-purpose car running club days and driver coaching, AST 5200 2-way is where most serious F8X/G8X builds land. For time attack, endurance, or a dedicated track car, MOTON 2-way or 3-way is the correct spec. The 1/2/3-way blog walks through this in detail.

Do I need to keep factory M Adaptive damping on my G8X?

No — but if you want to, the AST ALS (Adjustable Lowering Spring) system is the correct choice. It's engineered to work inside the factory damper's operating range, so the adaptive system stays in spec. If you're moving to full coilovers, you'll replace the factory dampers entirely, which removes M Adaptive — and that's fine, because the AST and MOTON dampers give you a broader tuning range than the OEM system ever offered.

Are AST and MOTON coilovers rebuildable?

Yes. Every AST and MOTON damper is fully serviceable. Seals can be replaced, oil refreshed, and the internal valving respec'd for a new spring rate, aero package, or shift from street to competition use. A well-maintained set lasts decades rather than being a consumable. This is one of the core reasons the range is worth the initial outlay.

RWD vs xDrive G8X — does it matter?

Yes. Front spring rates and damper valving differ between RWD and xDrive G8X, and the part numbers are not interchangeable. When you order, confirm your variant — or send us a message through the product page and we'll spec the right kit.

What's the lead time?

AST and MOTON are built to order at the Dutch facility. Typical lead time is around four weeks for the standard AST range; MOTON and custom-spec AST builds can run longer. If you need it faster for a specific event, talk to us before you order — we can sometimes expedite a build, and occasionally there's stock available.

Do I need to order camber plates separately?

AST 5100 Competition, 5200, 5300, and the MOTON range for F8X/G8X ship with camber-adjustable front top mounts as standard. You don't need to order them separately. Suspension Secrets Camber & Caster Plates are a separate upgrade if you want additional caster adjustment beyond what the coilover mounts provide — useful on dedicated track cars.

Do I need a wheel alignment after fitting?

Yes, always. Any ride-height change alters camber, toe, and caster — so a full four-wheel alignment is essential after installation. If you're lowering significantly or running the car on track, pair the alignment with Suspension Secrets adjustable arms for the geometry range the OEM parts don't provide.