Originally posted by chi town brat
B series are a DOHC (dual overhead cam) 1.6 to 1.8L motor. They are Non and Vtec engines. One example is the LS motor which is Non-Vtec. Some block codes are B16A SIR I, B16A SIR II, B18C5 (Type R), B18C (LS) or (GSR), B20 (CRV block)
H series are a DOHC (dual overhead cam) *don't know the liter*. The most popular is the H22A JDM from the 92-95 Prelude.
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b series are from 1.6 to 2.0 liters. the number after the letter engine code indicates the displacement (example: b16 is 1.6 liters, b20 is 2.0 liters).
also, h series are 2.2-2.3 liters. h22=2.2 liters, h23=2.3 liters
honda and nissan designate diplacement in the engine code (sr20=2.0 liters, rb26=2.6 liters, etc.)