Will it alone be able to Start my overnight cold LA318 V8( 5.2 liter) engine in~ 70F ambient temps with PP 10w-30 SN+ in the sump? I suspect this 18 AH made in China AGM battery would have about 170CCA, if it were rated. It supposedly has 18mÎ© resistance and I have measured its resistance to be in this range. I'll have ~ 3 feet of doubled 8awg wire passing current from 18 AH battery to battery cables. They will be removed from the main battery. My starter is rated at 1400 watts, or 140 amps at 10 volts. The Highest I have seen my Digital ammeter go during starting has been 128 amps, but I have not watched it lately since my reqular starting battery has aged significantly and its voltage retention is not as good as when i did note the 128 amp reading. Most of the reason I got this 38$ AGM battery was for assisting my well Aged current battery when it becomes too compromised tp start the engine by itself, at some point in the future. So anybody want to guess whether this new, healthy, fully charged UB12180 chinese AGM battery, can start my engine by itself? If SO, how low will its voltage fall? Guesses? My engine usually cranks for less than a second with the full size battery before catching, and I have not started it in two weeks. I'll have actual Data captured as to Peak Amperage and Wattage, and minimum voltage when I perform the test Midday tomorrow. If this battery can indeed start this engine, it will give good indications just how much degradation has to happen to a much larger starter battery before it fails to start an engine. Seems most people will say a battery is still 'going strong', Until the day it fails, when its CCA rating( and capacity) is basically falling since day one, the rate at which it falls dependent on how well the battery is recharged to full, how long it remains in an undercharged state, and the average battery temperature.