Mercedes-AMG GT Lowering: KW H.A.S. Review 2016-21

The KW H.A.S. kit is a height-adjustable sport spring set designed for the 2016-2021 Mercedes-AMG GT, GT S and GT C (chassis C190) that lets you lower the car up to 25 mm at the front and 30 mm at the rear while keeping the factory AMG Ride Control adaptive dampers fully functional. That last point is the whole reason this kit exists. The AMG GT is a long-hood, front-mid-engine sports car built around a 4.0-liter M178 twin-turbo V8 (469 hp in the GT, 503-515 hp in the GT S, 550 hp in the GT C) and a rear transaxle 7-speed dual-clutch gearbox — a chassis that leaves a very visible fender gap from the factory. In our Tampa, FL shop, the KW H.A.S. is the kit we reach for when an AMG GT owner wants a lower, planted stance without giving up the adjustable ride quality that makes these cars livable. This review covers exactly what the H.A.S. does, how far it drops the car, how it compares to fixed sport springs, and what the install involves.

What is the KW H.A.S. kit for the Mercedes-AMG GT?

The KW H.A.S. (Height Adjustable Spring) kit is a set of threaded, corner-adjustable lowering springs that bolt onto the factory AMG GT struts and dampers. Unlike a full coilover, it does not replace the shocks — it replaces only the springs and adds a threaded lower spring perch, so the car retains its OEM AMG Ride Control electronic dampers and every drive mode (Comfort, Sport, Sport+, Race) keeps working exactly as it did stock. KW builds the springs from high-strength, multi-coated chrome-silicon spring steel and backs the kit (part number 25325080) with a limited lifetime warranty and no mileage restriction. Because the ride height is set with a threaded collar rather than a fixed spring, you dial in each corner in millimeter increments, then corner-balance the car — something a fixed spring simply cannot do.

For a car like the AMG GT, that matters more than usual. The C190 ships with adaptive dampers as standard on GT S and above, and any lowering solution that ignores them either throws a suspension fault or forces you into an expensive full-coilover conversion with an electronic damper cancellation module. The H.A.S. sidesteps that entirely. It is, in KW's lineup, the bridge between basic lowering springs and a full Variant 3 coilover: adjustable height, factory damping, no electronics headache.

How much does the KW H.A.S. drop the AMG GT?

The KW H.A.S. lowers the Mercedes-AMG GT 0-25 mm (up to roughly 1 inch) at the front axle and 10-30 mm (about 0.4-1.2 inches) at the rear. Because the perch is threaded, you are not locked into a single figure: you can run an aggressive full drop for a track-day stance or back it off to a modest 10-15 mm street setting that still clears steep Tampa driveways. Most owners we set up land around 18-22 mm up front and 20-25 mm out back, which closes the worst of the factory fender gap while preserving enough bump travel for daily driving. The rear range starts at 10 mm rather than zero because KW's engineers biased the kit toward a level or slightly rear-raked stance that suits the GT's long-hood proportions.

Lowering a 3,600-3,700 lb sports car also lowers its center of gravity and reduces body roll, and because you can corner-balance the H.A.S., you can even out cross weights on a car whose driver-side mass would otherwise sit unevenly. The result is sharper turn-in and a flatter attitude under load without the crashy secondary ride you get from cheap fixed springs — the OEM adaptive dampers are still doing the damping work in whichever mode you select.

KW H.A.S. vs H&R Sport Springs: which lowering kit for the AMG GT?

The two proven lowering paths for a C190 with AMG Ride Control are the KW H.A.S. adjustable springs and the H&R Sport Springs. Both keep the factory adaptive dampers, but they solve the problem differently: the KW is a height-adjustable system you can fine-tune and corner-balance, while the H&R is a fixed-rate performance spring that delivers a set drop of roughly 25 mm front and 20 mm rear at about a third of the price. If you want a set-and-forget lowering for the least money, the H&R is excellent value at $594.15. If you want to dial in a precise stance, corner-balance the car, and have room to adjust after fitting new wheels or tires, the KW H.A.S. is worth the premium.

How do you install KW H.A.S. springs on an AMG GT?

Installing the KW H.A.S. is a spring swap, not a full strut replacement, so it is well within reach of an experienced shop or a competent DIYer with the right tools. Plan on roughly 4-6 hours. Each corner comes apart the same way: safely support the car and remove the wheel, unbolt the strut or damper assembly, use a proper spring compressor to separate the OEM spring, and fit the KW spring with its threaded perch. Set your target ride height by threading the collar before you reinstall, since fine adjustment on the car is easier if you start close. Because the H.A.S. reuses the factory dampers, there is no electronic module to wire and no coding required — AMG Ride Control simply keeps working.

Two things are non-negotiable after the install. First, a professional four-wheel alignment: lowering any AMG GT changes camber and toe, and the C190's double-wishbone geometry is sensitive enough that skipping alignment will scrub the inner edges off a set of tires fast. Second, corner-balancing if you want the most out of the adjustability — it is the single biggest reason to choose the H.A.S. over a fixed spring. Owners who plan to eventually run a full KW Variant 3 coilover on a track car will need the KW electronic damping cancellation (ESC) module below, but H.A.S. buyers do not: the whole point of this kit is that it keeps the OEM electronics happy.

What pairs well with lowered AMG GT suspension?

Once the stance is dialed in, the two upgrades our AMG GT customers add most often are brakes and cooling — both because a lower, harder-driven GT tends to see more track and canyon use. On the brake side, GiroDisc's two-piece slotted front rotor rings drop rotating and unsprung mass versus the heavy one-piece factory iron discs and shed heat better on repeated hard stops, all while bolting to the OEM hats and calipers. On the cooling side, the M178 twin-turbo V8 lives in a tight engine bay and is heat-sensitive on track; a CSF aluminum heat exchanger adds core volume and keeps intake temperatures down when you start using all 500-plus horsepower. Both are direct-fit and complement a lowered car that is being driven the way AMG intended.

KW H.A.S. for the AMG GT: pros and cons