OEM Honda S2000 Clutch Disc Only. Honda Part# 22200-PCX-055 This is our recommended choice for all basic n/a S2000's (Kswap or stock F). A more aggressive clutch setup will transmit more shock and harmonics to the rest of the driveline. Keeping an OEM clutch setup will help buffer that shock.
Is your AP2 slipping the clutch on fast shifts? upgrade to this AP1 Slave and ditch that delay valve. Do be warned- the delay valve has a purpose, and its to reduce shock to your drivetrain.
Is your clutch pedal feeling a little funny? This could be your issue. If left ungreased (or using the wrong grease) the clutch release bearing will wear at this guide. If you've got 150+ miles on your S2000, you may want to just replace this if you're already pulling the trans for a new clutch.