[MOTORHEAD]

Dennis:
Evidently your battery ground cable is making connection to the frame but not to the engine. Remember the engine is isolated from the frame by the Rubber engine and transmission mounts.
Take your frame/ground cable off and make sure its clean and bare metal. Reinstall it, but add a braided flat cable ( a battery ground strap with "eye" terminal at both ends) to that same connection. Bolt the other end of the strap to a large engine bolt
(bell housing, starter mtg, engine side of eng mount, timing chain
cover, all will work) Just remember all connections must be metal to metal, no paint allowed.
I just realized from your last post, your battery must be in the rear of the car. If this is so, and if your battery ground cable is short and connects to the frame at the rear, then make sure those connections are good, and add a ground cable to the front
of the frame and connect other end to engine as previously described.
Basic Electricity,Direct Current 101 is herby concluded !!
Give a holler if you have further problems.
Cheers,
Ted