Chase Bays - Clutch Master Cylinder Adapter - Nissan 240sx S13 / S14 / S15This product is designed for those who need or want to upgrade to a Tilton 0. 625" (5 8) or 0. 75" (3 4 Larger Bore) Clutch Master Cylinder on their S chassis without cutting or drilling their firewall. Some transmission swaps require a larger bore clutch master cylinder and since there isn't a larger Nissan one you can swap in this is the best method. Additionally, this product is much more aesthetically pleasing than the ugly Nissan cylinder, the