Is it time to replace your race suit? Let’s get you track-ready. 
BC Racing Coilovers Proton Satria are a direct-fit damper and spring package, sold as a complete four-corner kit. Chassis code C99. Fits 95-05 cars. Default spring rates are front 7 kg/mm / rear 5 kg/mm.
The height adjustment runs on a separate lower bracket, so you can drop the car without winding preload into the spring. Ride quality stays where the damper valving put it rather than getting progressively harsher the lower you go.
BC Racing Coilovers Proton Satria specification
| Vehicle | Proton Satria (95-05) |
|---|---|
| Chassis code | C99 |
| Manufacturer | Proton |
| Brand | BC Racing |
| Default spring rates | Front: 7 kg/mm / Rear: 5 kg/mm |
| SKU | BCR-ZK-04 |
Available kit configurations
Each configuration is the same damper and spring package with a different top mount arrangement. The kit code is the BC Racing part number for that build.
| Configuration | Kit code | Top mount |
|---|---|---|
| V1 Series – VA: Pillowball front / rubber or no rear | ZK-04-V1-VA | a pillowball front mount with rubber at the rear |
Spring rates and what is in the box
This kit ships at 7 kg/mm front and 5 kg/mm rear. The rates are matched front to rear for a balanced setup on the road. Rates are chosen by BC Racing per application, so they suit a fast road and occasional track car as supplied. If the car is built for something more specific, a track weapon or a car carrying a lot of aero, the rates can be changed without replacing the dampers.
The kit covers all four corners and includes the dampers, springs, lower brackets, locking collars and the adjuster spanners. Top mounts depend on the configuration you pick from the table above. Anything that is worn on the car already, drop links, bushes, top mount bearings, is worth checking while the suspension is apart.
Fitting and setting up BC Racing Coilovers Proton Satria
Set corner heights on level ground with the driver weight accounted for, then roll the car and settle the suspension before measuring again. Ride height changes on the bracket, damping on the adjuster knob.
Set the adjusters mid-range to begin with. Adjust in small steps and change only the front or only the rear at a time, otherwise you cannot tell which change did what.
The dampers are rebuildable. When they eventually need attention they can be stripped and revalved instead of binned, and spring rates can be changed later without replacing the whole kit.
Worth reading if you are new to this: how a coilover works and why height and preload are separate adjustments.
BC Racing Coilovers Proton Satria questions
Will BC Racing Coilovers Proton Satria fit without modification?
The kit is cut to the Proton Satria damper and strut dimensions and uses the standard mounting points on the C99 chassis. No cutting or welding is needed for a standard car.
How low will the Proton Satria go on these?
Height is adjustable across the full range of the lower bracket. How low you can usefully run depends on your wheel and tyre size and how the car is used, so set it to suit how the car is actually used.
What spring rates do BC Racing Coilovers Proton Satria come with?
Front: 7 kg/mm / Rear: 5 kg/mm as standard. The springs are a standard ID, so rates can be changed later without replacing the dampers.
Do I need an alignment afterwards?
Yes. Camber and toe both move as the car comes down, so book the alignment once the ride height is set and the suspension has settled.
Are these road legal?
Adjustable suspension is legal for road use in the UK. Keep the ride height sensible, make sure nothing fouls at full lock or full compression, and tell your insurer the car has been modified.
If you are not sure which configuration suits your car, send us the registration and what the car is used for and we will confirm the right BC Racing Coilovers Proton Satria spec before you order.
More from this range: BC Racing coilovers. Other Proton kits: Proton S70 FWD, Proton Inspira, Proton Waja/Gen 2.