BC Racing Coilovers – Honda Civic Si (Usdm) (14-15) [FB6/FG4]

BC Racing Coilovers Honda Civic Si (Usdm) replace the standard dampers and springs with an adjustable, rebuildable setup. Chassis code FB6/FG4. Fits 14-15 cars. Default spring rates are front 6 kg/mm / rear 6 kg/mm.

Because height is adjusted at the lower bracket, dropping the car does not add spring preload. You keep the full damper stroke instead of running out of travel at the bottom.

BC Racing Coilovers Honda Civic Si (Usdm) specification

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.

Which series for the Honda Civic Si (Usdm)?

• BR Series gives you 30-way rebound adjustment and full height adjustment independent of spring preload.
• RM Series gives you a race-oriented build with inverted damper bodies.
• ER Series gives you external reservoirs for more consistent damping under sustained load.
• ZX Series gives you raised ride height for soft-road and overland use.

Spring rates and what is in the box

This kit ships at 6 kg/mm front and 6 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 Honda Civic Si (Usdm)

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 Honda Civic Si (Usdm) questions

Will BC Racing Coilovers Honda Civic Si (Usdm) fit without modification?

The kit is cut to the Honda Civic Si (Usdm) damper and strut dimensions and uses the standard mounting points on the FB6/FG4 chassis. No cutting or welding is needed for a standard car.

How low will the Honda Civic Si (Usdm) 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 Honda Civic Si (Usdm) come with?

Front: 6 kg/mm / Rear: 6 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.

Not sure which top mount option you need? Send us the reg and how the car gets used and we will confirm the BC Racing Coilovers Honda Civic Si (Usdm) spec.

More from this range: BC Racing coilovers. Other Honda kits: Honda Prelude FWD, Honda Acura Integra FWD, Honda Civic/CRX FWD.