Skunk2 305-05-5140 Pro-Series Camshaft Required: Pro Series Valve Springs, Titanium Retainers Recommended: High-compression, fuel pressure regulator and/or upgraded fuel injectors, VTEC controller, modified ECU, deep valve pockets Fitment : 1999 - 2000 Honda Civic (Si). 1994 - 1997 Honda Civic del Sol (VTEC). 1992 - 2001 Acura Integra (GS-R, Type R)