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AST Suspension 5100 Series 1-Way Coilovers (Divorced Rear - Includes Front Top Mounts Only) ACT-B1101S - 2002-2008 BMW Z4 3.0 Coupe-Convertible (E85-E86)
The 5100 Series shock absorbers for the 2002-2008 BMW Z4 3.0 Coupe-Convertible (E85-E86) utilize inverted / upside down technology. The inverted design is race proven technology and produces an extremely strong damper, providing better suspension geometry under heavy lateral and braking loads as seen in a road and track environment.
The 5100 Series shock absorbers give your car a better performance than the standard twin tube design. With the 5100 Series suspension you can adjust rebound with one knob. The adjust platform allows you to adjust the ride height of your car. AST suspension shock bodies are specially designed to keep maximum stroke, even with a lower ride height.
How a Monotube design works?
Monotube design is essential for performance. The oil and nitrogen are separated by a floating piston, and allows the use of a larger piston, increasing the damper performance and sensitivity felt by the driver, all this added together produces more grip, gives more control and driver feedback from your vehicle.
What is a rebound adjustment?
Rebound controls the rate of extension of your shock absorber. By changing the rebound you can directly change the characteristics of the vehicle.
- Floating piston design with high pressure nitrogen means no cavitation around the piston.
- 14mm diameter internal shaft.
- 44.5 mm diameter shaft struts, inverted.
- Steel cylinder body shocks, inverted.
- High end, track ready suspension.
- Rebound adjustable ('Singles').
- Low friction seal.
- Adjuster knobs permanently mounted on the dampers.
- Designed to use OEM top mounts.
- Rubber bushings for 'eye' shock mounts.
- Includes springs.
- Optional spherical top mounts.
- Optional DLC (diamond like carbon) coated shafts.
- Optional DDP (double digressive piston).
- Double Digressive Pistons are recommended for use on the non-driven wheels.
- 4WD/FWD vehicles: DD pistons for both rear axle struts/shocks.
- RWD vehicles: DD pistons for both front axle struts/shocks.
- Optional custom valving.
- Part Number: ACT-B1101S
- Product: AST Suspension 5100 Series 1-Way Coilovers
- Adjustment: 1-Way
- System: Front Coilover, Divorced Rear Coilover
- Product Note:
- Front/Rear Ratio: Front = 60% / Rear = 40%
- Strut/Shock Type: Front: Clamp McPherson strut / Rear: Eye 2 pin strut
- Model Years: 2002-2008
- Make: BMW
- Model: Z4
- Chassis: E85-E86
- Spring Kit: Included
- Top Mounts: Includes Front Only
- Front Top Mounts: TMA-B01-A1-20F - Camber adjustable
- Optional Front Top Mounts (Additional Cost): Not Available
- Optional Rear Top Mounts (Additional Cost): Not Available
- Adjustable Front Droplinks (Additional Cost): Part Number: DLA-BMW1-S
- Adjustable Front Droplinks Required? Yes
- Adjustable Rear Droplinks Available? No
- Adjustable Rear Droplinks Required? No
- DDP Pistons Included? No
- DDP Pistons Available (Additional Cost): Yes
- DLC Coated Shafts Included? No
- DLC Coated Shafts Available (Additional Cost): Yes
- QDC Included? No
- TUV Approved?
- Comments: Works with OE top mounts.
- 2002 BMW Z4 3.0 Coupe-Convertible (E85-E86)
- 2003 BMW Z4 3.0 Coupe-Convertible (E85-E86)
- 2004 BMW Z4 3.0 Coupe-Convertible (E85-E86)
- 2005 BMW Z4 3.0 Coupe-Convertible (E85-E86)
- 2006 BMW Z4 3.0 Coupe-Convertible (E85-E86)
- 2007 BMW Z4 3.0 Coupe-Convertible (E85-E86)
- 2008 BMW Z4 3.0 Coupe-Convertible (E85-E86)
We are typically very quick and have a 24-48 hour turnaround time (this applies to products we have readily available at the warehouse and not a product that requires special order). Transit time depends on your order and which warehouse we are shipping from, but typical transit times are between 5-7 business days from one side of the US to the other. Larger items like bumpers and body kit conversions can take up to 10 business days to get you from time of ship.
Majority of the items we offer do ship free to the lower contiguous 48 states. States that require plane or boat to reach (such as Hawaii, Alaska, Puerto Rico, etc) do NOT qualify for free shipping. Larger items such as bumpers, hoods, fenders, also do NOT qualify for free shipping. Please contact us to inquire about international shipping costs. During checkout, you will know which items ship free and which have shipping costs associated with them. In general, larger/heavier items will have additional shipping costs (body kits, wheels/rims, etc)
Even though everything can be shipped internationally, sometimes the cost is simply just too high and doesn't make sense to do so. We're here to make sure you have a great shopping experience, so if you have a product(s) you want to inquire about, please contact us at email@example.com
Yes, we do price match reputable competitors in the marketplace. If you find a product cheaper elsewhere, please email us the (1) link of the product from our website and (2) the link to the competitor site. We will make an assessment on our end if we are able to price match or not and respond to you via email.
Typically you have 14 days to return a product you purchase when you change your mind. Damaged and improperly installed products are NOT eligible for returns. Shipping fees may be assessed and not refunded based on criteria as well as restocking fees. Please see our FAQ page for more details.
Unfortunate Kies Motorsports no longer does customer installs. Our HQ is solely reserved for filming, office space, and shipping/receiving.