BKR5E-11 for ka24de, BKRE6E-11 for stock boost on Ka24det or SR
BKRE7-11 or colder if you are running over stock boost or trying to limit detonation.
Too hot of a plug will cause you to misfire, and mess up your car.
Gap all plugs to .028 or .030.
All the above mentioned plugs are $2...