What size battery is needed?
A battery should be big enough to allow reliable cold starting. The standard recommendation is a battery with at least one Cold Cranking Amp (CCA) for every cubic inch of engine displacement (two for diesels). CCA rating is an indication of a battery’s ability to deliver a sustained amp output at a specified temperature. Specifically, it is how many amps a new, fully-charged battery can deliver at 0 degrees F for 30 seconds and still maintain a minimum voltage of 1.2 volts per cell. A rule of thumb says a vehicle’s battery should have a CCA rating equal to or greater than engine displacement in cubic inches. A battery with a 280 CCA rating would be more than adequate for a 135 cubic inch four-cylinder engine, but not big enough for a 350 cubic inch V-8. Battery manufacturers have been trying to outdo one another by introducing batteries with higher and higher cold cranking amp ratings. There was a time when a battery with a 550 CCA rating was considered a powerful battery. Now there ar
