The cold cranking amps (CCA) of a battery seems to be regarded as the more important parameter on this thread. This relates to the ability of the battery to supply enough current for the starter motor to turn the engine at adequate speed for it to start, and is temperature related. Whilst important this gives no indication of how long it can supply this current.
Its the capacity of the battery measured in amp hours (Ah) that should be considered of greater importance especially given that the engine may require several revolutions before firing. Furthermore any background load when car is not in use such as an immobiliser, will be better catered for by a battery of greater capacity than the puny 30 Ah original. Suggest a minimum of 40 Ah which will typically supply more than enough CCA.
Even an 850cc Moto Guzzi V twin motorbike had a 32 Ah battery as standard.
