Intake Valve Opens (IVO): 10° BTDC (Before Top Dead Center)
Intake Valve Closes (IVC): 40° ABDC (After Bottom Dead Center)
Exhaust Valve Opens (EVO): 40° BBDC (Before Bottom Dead Center)
Exhaust Valve Closes (EVC): 10° ATDC (After Top Dead Center)
It's important to note that these specifications may vary slightly depending on the specific model year and engine variant of your Mazda B3000. It is always recommended to refer to the vehicle's service manual or consult with a qualified mechanic for accurate and up-to-date information.