OK I am getting to the bottom of this random no start issue.
I think the battery and alternator are fine because after a few tries for turning the key and just hearing a click, the car starts up fine even sitting for a few days, I think the issue is in the stock wiring, see links below:
https://www.norotors.com/index.php?topic=23885.0https://grandmighty.github.io/grandmighty/2016/03/starter-booster-relay/So I bypassed by clutch switch, and alarm system hoping this would help but it did not.
My next step is to build this relay to help supply constant voltage to starter solenoid, has anyone done this? Im assuming everyone with a swapped rx7 will have these issues.
So I ordered a hella 40amp relay with 5 pin harness, i followed everything on this grand mighty write up and wire 87 that connects to terminal S on the starter.
I was surprised this to be a small gauge wire, is this only passing voltage signal to the solenoid? and all the voltage is running through the large wire on terminal B? I know 87a is a spare and its a large gauge wire, please confirm if anyone has done this that was my only concern before I install, thanks.
Position 86 to Ground ring terminal on starter bolt
Position 30 to Terminal B on starter 12V
Position 85 gets spliced into the OEM black / red mazda wire that used to go to terminal S (this now acts as the signal wire)
Position 87 is the one I have in question, this wires into terminal B on starter solenoid and I was surprised this was with the smaller gauge wire.