Ok I got an 86 full size bronco with a 302 efi automatic. I have been fixing electrical issues left and right like the alt wasn't charging wasn't starting finally got all that squared away but I still am having issues when I need to start truck when it is hot. This thing is all stock. Changed the starting selinoid battery cables and grounds. When the truck is hot it act as if the battery is dead when ya try and start. It will crank barley. Now I checked voltage at battery 12.5 volts before starting but on the starting silenoid where the where goes to the starter motor it drops down to about 6-8 volts. Because of this I made mere grounds and still have same issue. My grounds go from battery to where the jack gets mounted another from the battery to the smog pump bracket and another from the intake manifold to another hole where the jack gets mounted to. Using high quality 4 gauge wire for grounds and battery cables. The one thing I really noticed was that the wire going to starter and the positive battery cable gets really hot. If I wait about an hour or so truck starts with no issues. All metal has been sanded down to bare metal for all grounds. Please help.