Unless that braided ground strap is brand new, it's probably got a severe amount of voltage drop due to internal corrosion at the end terminals. It also adds two extra connection points to corrode. I always use a heavy ground cable directly from the block or bell housing to the battery so all the current that braided cable needs to carry is for lights and other low amperage circuits.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!