Track-Autocross CS1 Coil-overs for RSX & Civic EP

Is your RSX track-ready yet? Is it time to find a sunny Saturday and some open road?

If you are building up a ‘weekend fun’ ride with your RSX or ‘EP’ Civic hatchback, we have you covered. For a decade, we have tracked these vehicles on our Progress CS1 coil-overs and even won the coveted Super Street Challenge. Now you can purchase one of our most successful combinations and bolt-on a track proven CS1 Coil-over system. The dynamic improvements will be apparent immediately; faster cornering speed, less body roll and improved balance. Your 'track rat' will be better handling, easier to drive, and way more fun!

Our unique front strut housings are manufactured in-house. The housings are 20mm shorter than OEM for additional wheel travel, and the steering arms have built-in compensation for the bump-steer present at lower ride heights with these vehicles. The housings are plated with a Mil-spec electroless nickel process and assembled using anodized 6061 spring perches and end caps. Our damper settings are aggressive and well-suited for both Street/Sport and Track/Autocross spring options.

This Progress track-oriented race-spring combination is new for 2017. The spring rates are 425#/inch front and 850#/inch rear, a considerable jump up from the Street/Sport 350/650 combination. The front springs have our exclusive ‘barrel shaped’ spring body for additional clearance for the threaded strut housings. The new springs feature High-Tensile Chrome Silicon spring wire, are shot-peened and loaded tested for perfect fit & function.

The high-rate combination has two specific-fit springs for very aggressive street and track day use. It will ride pretty well on smoother roads, and will communicate smaller bumps and wheel motion up into the cabin. On the highway and good roads it’s very firm & positive. This combination with more spring rate will be great for track days, and will also improve 'drag launch' performance.

#75.0102.4285           for RSX          web: $1045    

#75.1006.4285            for Civic          web: $1045

#75.1007.4285            for Civic Si      web: $1045

Q: Why is the rear spring rate so much higher than the front rate?

A: Because of the motion ratio of the suspension. The front axle is more sensitive to increasing the rate, because the wheel/spring motion is 'direct' at a 1:1 ratio. The rear is approximately 2:1, so the spring rate increase in the rear has less effect on the wheel rate. So to balance the chassis requires a greater increase to the rear spring rate than the front.