2017 2021 Honda Civic Type R FK8 Performance Mods PRL Motorsports Girodisc Rear 2 piece Rotors 17 21 Civic Type R (FK8) 22+ Civic Ballade Sports 17+ Civic Type R FK8 Mesh Grill Ballade Sports 2015+ Civic Type R FK2 FK8 Rear Big Rotor Kit Civic Type R FK8 FL5 2 pc Rear Rotors Paragon Performance. Ballade Sports 2015+ Civic Type R FK2 FK8 Rear 330mm Rotor Kit is a 2 piece CNC billet aluminum bell hub with an iron 330mm disk. The FK8 uses a large 350mm front brake disk, with only a 305mm rear rotor. Our kit increases the rear brake disk by 25mm 1 inch to help even out the brake bias. The larger brake rotor disk offers higher lateral strength which increases stopping power. This is a great add on to match the new 2020 Fk8 2 piece rotor that now comes standard. 2015 16 Civic Type R FK2 compatible as well per Euro customers confirming the FK2 and FK8 use the same braking hardware. With the increase of 8. 2% in size, there are two most common questions: Isn't the extra inner space on the rotor surface not being utilized because of the pads being same OE size? Answer: correct, not used for a reason. You can see in the picture the caliper and pad assembly moved outward by 12. 5 mm. The pad size did not change, and you don't want to change the pad size unless you also upgrade the master cylinder and brake booster designed in the FK8. The FK8's master cylinder is designed with a set or defined pressure that's multiplied by the brake booster. Increasing the pad size or surface area without upgrading the master cylinder and brake booster, you've effectively reduced your pressure at the pad to rotor contact area reducing your braking force. How does a larger diameter make for more braking force? Answer: no, braking force is increased due to increase in "lever" length. Imagine you push on a lever that's 1 foot long around a center point or fulcrum. Now lengthen that lever by 50% to 1. 5 foot long. The result is more moment of torque. You work less but generate more torque; hence higher degree of brake torque or stopping power. This means the caliper piston pads assembly has to work 8. 2% less but generates more torque ala more braking force. By simply increasing rotor size, you're already increasing braking force without doing anything else. *Brake rotors are made to order*